Geological Society of Australia
ABSTRACTS Number
85
1
Conference on Australasian Vertebrate Evolution Palaeontology and Systematics Melbourne April 2007
11th Conference on Australasian Vertebrate Evolution Palaeontology and Systematics Melbourne April 10-13 2007
Programme Abstracts
TROBE
MUSEUMVICTORIA
^^UfTl V ERS 1TY
ISSN 0729 01IX © Geological Society of Australia Incorporated, 2002 Citation for this volume: Warren, A. (editor), 2007. Conference on Australasian Vertebrate Evolution, Palaeontology and Systematics 2007, Geological Society of Australia Abstracts 85, 61p.
Example of citations for papers in this volume: Consoli, C.P., and Stilwell J.D., 2007. The vertebrate fauna of the Cretaceous-Paleogene Takatika Grit, Chatham Islands, New Zealand: insights into a new terrestrial and marine tetrapod assemblage on the edge of an austral volcano, in: Warren, A. (editor), 2007, Conference on Australasian Vertebrate Evolution, Palaeontology and Systematics 2007, Geological Society of Australia Abstracts 85, p. 25-26.
Copies of this publication may be obtained from: The Business Manager, Geological Society of Australia Incorporated, Suite 706, 301 George Street, Sydney NSW 2000, Australia, info@gsa.org,au
CONTENTS Conference Programme Abstracts
Early Vertebrates of Gondwana (Convenors John Long and Gavin Young) General Sessions Marine Mammals in Deep Time (Convenor Erich Fitzgerald) Posters
CAVEPS 2007 was supported by: MUSEUMVICTORIA
LA TROBE •UNIVERSITY
AAR (Tlic 3anpl Society of Victoria: PROMOTING SCIENCE SINCE 1854
CAVEPS 2007 COMMITTEE
John Long Anne Warren Stella Claudius Erich Fitzgerald Jillian Garvey David Pickering Timothy Holland Brian Choo
p. 4 p. 12
Conference Programme Friday 6 April-Monday 9 April Pre-Conference Field trip: Devonian, Carboniferous and Cretaceous (Coordinator Jillian Garvey) Monday 9 April Registration desk open 2.00-5.00: Foyer outside Age Theatre, Museum Victoria
Tuesday 10 April Registration desk open 8.00-4.00: Foyer outside Age Theatre, Museum Victoria
Age Theatre 9.00 Introductory remarks: Patrick Green (CEO, Museum Victoria), John Long
Early Vertebrates of Gondwana * student presentation
Venue: Age Theatre Chair: Gavin Young 9.20 Keynote Speaker: Clack, J.A. Devonian climate change, breathing, and the origin of the tetrapod stem group 10.00 Trinasjtic, K. New information on the morphology and phylogeny of Bullerichthys from the Gogo Formation, Western Australia 10.20 Morning Tea 10.50 Young, G.C. Eye muscle arrangement and function in basal jawed vertebrates - new evidence from Devonian placoderm fishes 11.10 *Brazeau, M.D. The neurocranium of an early Devonian acanthodian 11.30 Long, J. A strange new edentulous gnathostome fish from the Upper Devonian Gogo Formation 11.50 *Gess, R.W. Chondrichthyan fossils from the Famennian of South Africa 12.10 *Clement, A. A new holodipterid from the Late Devonian Gogo Formation, Western Australia 12.30 *Qiao, T & Zhu, M. A new tooth-plated dipnoan from the Middle devonian of Yunnan, China, and its phylogenetic relationships 12.45 Lunch
Chair: Kate Trinasjtic 2.00
*Choo, B. Redescription of the dermal skeleton of the basal Actinopteiygian fish Moythomasia
2.20
*Hunt, J. New Middle Devonian osteolepid material (lobe-finned fish) from Hatchery Creek, New South Wales
2.40
Zhu, M. Late Devonian sarcopterygians from Ningxia, northwestern China, and their biogeographic bearing
3.00
Young, G. New ideas on some tristichopterids (osteolepiform lobe-finned fishes) from the Late Devonian of Australia
3.20
^Holland, T. New description and the phylogeny of the tetrapodomoprh fish Marsdenichthys longioccipitus from Mt. Howitt, Victoria
3.40
Afternoon Tea
Chair: John Long 4.05
*Lu, J & Zhu, M. A new genus of the Tetrapodomorpha from the Posongchong Formation (Pragian, Early Devonian) of Zhaotong, Yunnan, China
4.20
Downs, J.P., Daeschler, E. B., Shubin, N. & Jenkins, F. A. Jr. The branchial skeleton of Tiktaalik rosae (Tetrapodomorpha: Elpistosteglia)
4.40
*Parker, K & Webb, J. The sedimentology of the mid-Visean tetrapod locahty at Ducabrook, central Queensland: depositional environment and palaeobiogeograpy
5.00
Warren, A. The Australian stem tetrapod Ossinoduspueri the distribution of sensory canals in early tetrapods
5.20
Mannering, A. and Hiller, N. A. Paleocene deep-water shark fauna from the southwest Pacific
5.40
Gottfried, M., O'Connor, P., Stevens, N., Roberts, E, and Ngasala, S. Recent discoveries from the Cretaceous and Paleogene of the Rukwa Rift Basin, Tanzania, including new Tanzanian fossil records of Neoceratodus and Protopterus (Dipnoi)
6.00
Icebreaker at Museum Victoria, Life and Sciences Gallery
Warren and Turner, 2004 and
Wednesday 11 April General Sessions Venue: Age Theatre Chair: John Long 9.00
Warren, A. and Rozefelds, A. New finds from the Tasmanian Triassic
9.20
Pawley, K. and Salisbury, S.W. Biomechanics of rhachitomous vertebrae in early tetrapods
9.40
Pickering, D. and Kool, L. A short history of Victorian Polar Dinosaurs and other vertebrates
10.00 *Consoli, C.P. and Stilwell J.D. The Vertebrate Fauna of the Cretaceous-Paleogene Takatika Grit, Chatham Islands, New Zealand: Insights into a new terrestrial and marine tetrapod assemblage on the edge of an Austral Volcano 10.20 Morning Tea
Chair: Steve Salisbury 10.50 *Fletcher, T.L., SaHsbury, S.W. and Cook, A.G. New pterosaur fossils from the Early Cretaceous (Aptian-Albian) of western Queensland, Australia 11.10 Salisbury, S.W., Molnar, R.E., and Lamanna, M.C. Sauropods from the midCretaceous (Albian-Cenomanian) Winton Formation, central-western Queensland, Australia 11.30 *Holt, T.R., Salisbury, S.W., Worthy, T.H., Sand, C. and Anderson, A. New material of Mekosuchus inexpectatus (Crocodylia: Mekosuchinae) from the Quatemary of New Caledonia 11.50 *Buchanan, L.A. New Eocene crocodiles from Queensland: implications for mekosuchine evolution 12.10 Lee, M.S.Y. Snake origins and the interaction of morphological and molecular data sets 12.10 Lunch
Chair: Michael Lee 2.00
*Moreno, K., Wroe, S., Clausen, P., McHenry C., D'Amore D. and Rayfield, E. Functional morphology of a varanid skull as revealed by finite element analysis
2.20
^Worthy, T.H. Phylogeny of Miocene waterfowl: reality relies on overcoming homoplasy
2.40
Wood, J.R., ^Rawlence, N.J., Cooper, A. Coprolites shed new light on the diet of late Holocene moa in southern New Zealand
3.00
^Nguyen, J. and Hand, S. A dromomithid bird Barawertornis tedfordi from the midCenozoic of Riversleigh, northwestern Queensland
3.20
Tennyson, A.J.D. and Scofield, R.P. Maquarie Island Holocene fossil bird remains
3.40
Ksepka, D., Clarke, J., Smith, A., and Norell, M. A new eocene roller (Aves, Coraciodea) from North America: insights into early roller morphological evolution and biogeography
4.00
Afternoon Tea
Chair: Sue Hand 4.30
*Gurovich, Y. and Wilson, G. Dental morphology of Sudamericidae: gondwantherian mammals from the Cretaceous and Paleogene of Gondwana
4. 50
^Worthy T.H., Hand, SJ., Archer, M, Beck, R.M.D., Tennyson, AJ.D., Musser, A.M.; Jones, C., Douglas, B.J., and McNamara, J.A. A Miocene terrestrial mammal from New Zealand
5.10
Musser, A. M., and Jones R. K. The Early Cretaceous flora and fauna of Lightning Ridge, New South Wales from the Australian Museum collections
5.30 6.00
Venue: Age Theatre Fossil findings, news and controversy. The public will be invited to join conference delegates at a forum where several invited speakers will present short ^vignettes'.
7.00
Drinks and nibbles with the public
Thursday 12 April General Sessions Venue: Age Theatre Chair: Trevor Worthy 9.00
^Travouillon, K.J., Legendre, S., Archer, M. and Hand, S.J. Do cenograms work on marsupial faunas? Comparison with other palaeoecological techniques and implication for the Riversleigh faunas
9.20
Megirian, D., Prideaux, G., Murray, P., and Smit, N. A basis for the definition of Australian Neogene 'marsupial ages', and a rationale for doing so
9.40
*Beck, R.M.D., Godthelp, H., Archer, M., and Hand, S. J. Petrosals and tarsals of the early Eocene marsupial Djarthia murgonensis: implications for the evolution and biogeography of Australidelphia
10.00 ^Roberts, K. and Archer, M. Early pseudocheirid evolution revealed by the OligoMiocene localities of Riversleigh and Central Australia. 10.20 Morning Tea
Chair: Steve Wroe 10.50 Warburton, N. and Prideaux, G. Functional pedal morphology of Pleistocene kangaroos from the Nullarbor Plain 11.10 Price, G. Diprotodon dynasties: towards an understanding of the taxonomy and paleobiology of the largest-ever marsupial (Diprotodontoidea, Marsupialia) 11.30 *Camens, A. Diprotodontid footprints from the Pliocene of Central Australia 11.50 Murray P. and Megirian D. Palaeobiological significance of cheektooth wear and attrition in Wakaleo vanderleueri (Thylacoleonidae)
12.10 Cramb, J. Two new fossil dasyuromorphian genera and their significance 12.30 Lunch
Chair: Dirk Megirian 2.00
Wroe, S. and Milne, N. Convergence and remarkably consistent constraint in the evolution of carnivore skull shape
2.20
Price, G.J., Zhao, J. Feng, Y. and Hocknull, S.A. Constructing a spatially-constrained chronology of megafauna evolution and extinction in eastern Australia
2.40
Garvey, J., Cosgrove, R. and Pike-Tay, A. Wallabies and Wombats: new zooarchaeological interpretations of the Late Pleistocene occupation of Southwest Tasmania
3.00
^Duncan, J. Evidence of humans and megafauna at Lake Menindee, New South Wales
3.20
^Martinez, S. Palaeoecology of late Quaternary bat fauna from Mt Etna, easterncentral Queensland, and its response to environmental change: a project underway
3.40
*Bray, S., Austin, J., Bames, I, Weinstock, J., Shapiro, B., and Cooper, A. The evolution and genetic diversity of the extinct tremarctine bears
4.00
Afternoon tea
4.30
Wroe, S., Moreno, K., Clausen, P., McHenry, C. and Cumoe, D. Computer supermodelling of hominid facial form, function and feeding: why the heavy brow?
4.50
Drishti Workshop: Professor Tim Sendon, ANU, Canberra, Activity Room C
7.0
Conference Dinner: Via Veneto, 234 Lygon Street, Carlton
Friday 13 April Marine Mammals in Deep Time: Diversity, Distribution and Evolution Venue: Royal Society of Victoria, 9 Victoria Street, Carlton FAUNAS AND PALAEOECOLOGY Chair: Erich Fitzgerald 9.00
Keynote Speaker: Fordyce, E., The evolution of aquatic tetrapods in the southwest Pacific
9.40
*Fitzgerald, E. An evolutionary history of marine mammals in and around Australia
10.00 Gonzalez-Barba, G. The Late Oligocene marine mammal assemblage of the San Juan and Timbabichi Members (El Cien Formation), Baja Califomia Sur, Mexico
10.20 Morning Tea 10.50 Goedert, J.L., Barnes, L.G. and Furusawa H. The diversity and stratigraphic distribution of cetaceans in early Cenozoic strata of Washington State, U. S. A. 11.10 Kohno, N. Pelagic habitat preference in the origin of the otariid pinnipeds 11.30 Hampe, O. Considerations on the ecology of fossil sperm whales
SYSTEMATICS AND EVOLUTION Chair: Annalisa Berta 11.50 VoB, M, Discoveries of sirenian remains from the early Oligocene of the Rhine-Ruhr area (Germany) and a new look on the genus Halitherium 12.10 Furusawa, H. Origin and distribution of a large sirenian, Hydrodamalis 12.30 Lunch 2.00
^Fitzgerald, E.M.G. Taking the mystery out of toothed mysticetes: phylogeny and evolution of stem group Mysticeti (Cetacea)
2.20
Kimura, T. and Hasegawa, Y. Oldest Eubalaena from the Gonda Formation (latest Miocene-Early Pliocene), Japan and its implication for the evolution of right whales
2.40
*Churchill, M., Berta, A., and Demere, T. The systematics and biogeography of right whales (Balaenidae: Mysticeti)
3.00
Fordyce, R.E. New shark-toothed dolphin (Late Oligocene, New Zealand) elucidates the early history of the extinct Squalodontidae
3.20
*Charlton, K. Pliocene climate change and genetic divergence amongst southern Australian bottlenose dolphins {Tursiops sp.)
3.30
Afternoon tea
4.00
Kemper, C. and Hale, P. Taxonomy of bottle nose dolphins: are we on the right track?
4.20
Moreno, I.B.. Skull morphology of Atlantic spotted dolphins, Stenella frontalis (Cuvier 1829), in Brazil: comparisons between North Atlantic and Caribbean populations
PALAEOBIOLOGY Chair: Ewan Fordyce 4.40
Beatty, B.L. Dental Structure and Wear in the Desmostylia and Sirenia
5.00
Berta, A., Demere, T.A.,.McGowen, M.R and Gatesy, J.G. New insights into the evolutionary biology of mysticete cetaceans
5.20
Pyenson, N.D. and Sponberg, S. Reconstructing body size in extinct crown Cetacea using allometric scaling, phylogenetic comparative methods, and tests from the fossil record
5.40
Poster session: Marine Mammals in Deep Time
6.30
Farewell Drinks and Dinner: Standard Hotel, 293 Fitzroy Street, Fitzroy, Beer garden
Posters: Early Vertebrates of Gondwana, General Sessions *Bell, G. P., Geometric morphometric shape quantification using elliptical fourier analysis: an example from human frontal sinus shape and potential use in comparing palaeontological remains *Berrell, R.W., Sahsbury, S.W. and Yabumoto, Y. A new freshwater fish (Teleostei: Ichthyodectiformes) from the mid-Cretaceous (Albian-Cenomanian) Winton Formation of Isisford, central-western Queensland, Austraha Black, K. Ontogeny of the skull of Nimbadon lavarackorum, a mid Miocene zygomaturine (Diprotodontidae, Marsupialia) from Riversleigh, northwestern Queensland Burrow, C.J. Postcranial exo- and endoskeleton - ne'er the twain shall meet, or...? *Choo, B. Ray-fins of the Gogo: exceptional Devonian fossils shed light on the early evolution of actinopterygian fish *Faggotter, S.J., Sahsbury, S.W. and Yabumoto, Y.'A new possible halecomorph fish from the mid-Cretaceous (Albian-Cenomanian) Winton Formation of Isisford, central-westem Queensland, Australia Geddes, K., Salisbury, S.W. and Wilkinson, J. Preparation of the type material oilsisfordia duncani, a basal eusuchian crocodyliform from the mid-Cretaceous (Albian-Cenomanian) Winton Formation of Isisford, central-westem Queensland, Australia Hand, S., Worthy, T., Archer, M., Godthelp, H., Beck, R., Tennyson, A., Scofield, P. and Sige, B. New opportunities for testing competing biogeographic hypotheses about the origins of the Australasian bat fauna ^Holland, T. Description of a new specimen of Barameda decipiens (Rhizodontida) and heterochrony in the rhizodontid pectoral fin *Leahey L.G., Sahsbury, S.W. and Molnar R.E. Cranial osteology of Minmi sp., a basal ankylosaurid thyreophoran (Dinosauria: Omithischia) from the Early Cretaceous (Albian) Allaru Formation of Richmond, north- western Queensland, Australia *Louys, J. Limited effect of the Quaternary's largest super-eruption (Toba) on land mammals from Southeast Asia *Nair, J. and Salisbury, S.W. Osteology and biomechancis of the cms and pes in Rhoetosaunis brownei Longman (Dinosauria: Sauropoda) from the Middle Jurassic Injune Creek Group of Roma, south-westem Queensland
10
Price, G.J. and Hocknull, S.A. Koala conundrums: a new species of middle Pleistocene Madakoala (Phascolarctidae, Marsupialia) has implications for fossil vertebrates as biocorrelative tools Schroeder, N. and Spooner, N. Big bird and chicken little: the egg of Genyornis newtoni *Seegets-Villiers, D. Palynology of the Inverloch fossil site, Gippsland Basin, Australia "^Stefen, C. and Morlo, M.. A juvenile skull of Sarcophilus laniarius *Stefen, C. Preliminary results of tooth microwear between some marsupial and placental carnivores Warburton, N.M., Prideaux, G.J. and Harvey, K. Functional morphology of Pleistocene treekangaroos (Bohra) from the Nullarbor Plain
Posters: Marine Mammals in Deep Time: Diversity. Distribution and Evolution Bohaska, D.J., Barnes, L.G. and Godfrey, S.J. Araeodelphis natator Kellogg, 1957, the most primitive known member of the Platanistidae (Odontoceti, Cetacea) and a review of Platanistidae from Calvert Cliffs (Miocene, Chesapeake Group), Maryland, USA Gerholdt, J.M. and Godfrey, S.J. Pathological dolphin rostra from Calvert Cliffs (Miocene, Chesapeake Group), Maryland, USA Godfrey, S.J. and Barnes, L.G. A new genus and species of Late Miocene pontoporiid dolphin (Odontoceti, Cetacea) from the St. Marys Formation (Chesapeake Group), Maryland, USA Steffen Kiel, S. and Goedert, J.L. Dead whales as habitats: invertebrate communities and their evolutionary implications
Saturday 14 April-Sunday 15 April From Sea to Rainforest: Gondwana Marine Mammals and Polar Dinosaurs: Field trip (Coordinator: Erich Fitzgerald)
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Abstracts The Abstracts are listed in the order of presentation. Poster Abstracts are in two sections in alphabetical order.
Early Vertebrates of Gondwana: Palaeozoic vertebrates of Gondwana: phylogeny, biostratigraphy and biogeography DEVONIAN CLIMATE CHANGE, BREATHING, AND THE ORIGIN OF THE TETRAPOD STEM GROUP Jennifer A. Clack University Museum of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK, i.a.clack@zoo.cam.ac.uk Key words: Devonian, tetrapodomorph, climate, air breathing The diversification of the tetrapod stem group occurred during the late Middle through the Late Devonian, that is from the Givetian to Famennian stages about 385 to 365 milHon years ago. The relationships between the known taxa representing this radiation has currently reached a consensus so that interpretations of the order of appearance of tetrapod characters is possible. Lungs are thought to have been present in most early bony fishes. At some stage, the tetrapod stem group elaborated this system and their descendent land-based tetrapods became obligate air-breathers. Late Devonian tetrapodomorphs show enlargement of the spiracular region consistent with interpretion as a morphological correlate of air breathing, and accompanied by changes to the morphology of the pectoral fin consistent with an increase in a supportive role for that appendage, for example to raise the head out of the water. Estimates of oxygen levels during this period suggest that they were unprecedentedly low during the Givetian, Frasnian and Famennian stages (Bemer 2006). At the same time, plant diversification was at its most rapid, changing the character of the landscape and contributing, via soils, soluble nutrients, and decaying plant matter, to anoxia in all water systems (Algeo et al 2001). The co-occurrence of these global events may explain the rise of air-breathing adaptations in tetrapodomorphs, contributing directly to the rise of the tetrapod stem group. In contrast to recent studies, low atmospheric oxygen is not considered to be causal factor in the lack of fossils documenting the evolution of Early Carboniferous tetrapods (Ward et al. 2006). ALGEO, T.J., SCHECKLER S.E. 8l M A Y N A R D J.B., 2001. Effects of the Middle to Late Devonian spread of vascular land plants on weathering regimes, marine biotas, and global climate. In Plants invade the land - Evolutionary and environmental perspectives. P.O. Gensel & D. Edwards eds, Columbia University Press, New York, 213-236. BERNER, R.A., 2006. GEOCARBSULF: a combined model for Phanerozoic atmospheric 02 and C02. Geochimica and Cosmochimica Acta 70, 5653-5664. WARD, P.D., LABANDEIRA, C., LAURIN M. & BERNER R.A., 2006. Confirmation of Romer's Gap as a low oxygen interval constraining the timing of initial arthropod and vertebrate terrestrialization. Proceedings of the National Academy of Sciences 103, 16818-16822.
FURTHER SIGNIFICANT DISCOVERIES OF FISHES FROM LATE DEVONIAN COCO FORMATION, WESTERN AUSTRALIA John A. Long Museum Victoria, PO Box 666, Melbourne, VIC 3001, Austraha, jlong@museum.vic.gov.au Key words: Devonian fishes Gogo new taxa
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The Gogo Formation has yielded without doubt the world best preserved 3-dimensional Devonian fishes, some even showing patterns of muscles, nerves and circulatory systems (Long 2006, Trinajstic et al 2007). The 2005 Museum Victoria Gogo expedition, the most fruitful field collecting expedition to the site since the 1967 NMH-WAM expeditions, yielded the first ever records of two new classes from Gogo (acanthodians and chondrichthyans), as well as remarkable new material of the tetrapodomorph fish Gogonasus (Long et al 2006), at least two new lungfishes (Long, in press), a new Gogo palaeoniscoid (B. Choo, pers. comm.), further specimens of the basal sarcopterygian Onychodus jandemarrai (Andrews et al. 2006), with one showing articulated gill arches (not previously described), and at least one new ptyctodontid placoderm. Over 130 fish specimens were collected and intense acid preparation by Museum Victoria staff and students has seen a large number already completed. The new material forms the basis of two new Ph.D projects (Brian Choo, MV/ANU; Tim Holland, MV/ Monash) as well as an honours thesis on lungfish (Alice Clement, MV/MU). It is expected that the new specimens will all show new anatomical information relevant to their respective groups, and thus contribute significantly to our better understanding of the interrelationships and intra-relationships of the basal gnathostome, and in particular, the basal osteichthyan fishes. The expedition acknowledges ARC Discovery Grant DP 0558499 for support. ANDREWS, S.M., LONG, J.A., AHLBERG, P.E., BARWICK, R.E. & CAMPBELL, K.S.W., 2006. The structure of the sarcopterygian fish Onychodus jandemarrai n.sp. from Gogo, Western Australia: with a functional interpretation of the skeleton. Transactions of the Royal Society of Edinburgh: Earth Sciences 96, 197-307. LONG, J.A., 2006. Swimming in stone-the amazing Gogo fishes of the Kimberley. Fremantle Arts Centre Press, Perth, 320pp. LONG, J.A., YOUNG, G.C., HOLLAND, T., SENDEN, T.J. & FITZGERALD, E.M.C., 2006. An exceptionally preserved Devonian fish from Australia sheds light on tetrapod origins. Nature 444, 199202. TRINAJSTIC, K., MARSHALL, C., LONG, J. & BIFIELD, K., 2007. Exceptional preservation of nerve and muscle tissues in Late Devonian placoderm fish and their evolutionary implications. Biology Letters doil0.1098/rsbl 2006.0604.
NEW INFORMATION ON THE MORPHOLOGY AND PHYLOGENY OF BULLERICHTHYS FROM THE GOGO FORMATION, WESTERN AUSTRALIA. Kate Trinajstic School of Earth and Geographical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia, KTRINAJS@BIGPOND.NETAU Key words: Placoderm, arthrodire, phylogeny, evolutionary trends, The original description of Bullerichthyes fasciden Dennis & Miles 1980 was based on a partial headshield recovered from the Gogo Formation, Canning Basin, Western Australia. Further material recovered by John Long in 2000 permits a detailed description and reconstruction of the complete headshield. The new specimen consists of a preorbital plate, suborbital plate, pineal plate, central plates, marginal plate parasphenoid and gnathal elements. The rostral plate, although not preserved, is reconstructed. The second specimen is of an individual smaller than the holotype and so some ontogenetic characters within the eubrachythoracid arthrodires are discussed. A revised diagnosis is presented for the genus and a phylogenetic analysis for the bracythoracid arthrodires from the Gogo Formation is presented. Evolutionary trends, principally a reduction in body armour, increased flexability and a move toward durophagy, within the eubrachythoracid arthrodires are discussed. It is concluded that these changes resulted from several evolutionary mechanisms, including a combination of paedomorphic and perimorphic trends, and directional selection of polymorphic traits. DENNIS, K. & MILES, R.S., 1980. New durophagous arthrodires from Gogo, Western Australia. Zoological Journal of the Linnean Society 69, 43-84.
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EYE MUSCLE ARRANGEMENT AND FUNCTION IN BASAL JAWED VERTEBRATES NEW EVIDENCE FROM DEVONIAN PLACODERM FISHES Gavin C. Young Dept. Earth & Marine Sciences, ANU, Canberra, ACT 0200, Australia, gyoung@ems.anu.edu.au Key words: eye muscles, jawed vertebrates In a 3D world, vertebrates need at least six muscles to control eye movement - antagonistic pairs to push and pull in each of three directions. Comparative morphology and embryology of living vertebrates shows this (presumably ancient) arrangement to be highly conserved - the eye muscles 'appear in the lower vertebrates in essentially the same form as in man ... their number and nerve relations are the same in man as in the dogfish' (Neal 1918, p. 433). From the fossil record, the evidence of Devonian Placodermi (armoured fishes), the probable sister group to all other jawed vertebrates, can indicate the primitive gnathostome condition. The placoderm braincase includes thick lateral walls, with complete perichondral ossification of the cranial cavity and nerve and vessel canals, so the interpretation of internal cranial morphology is more robust than in other early vertebrate groups (Basden et al. 2000). Such rarely preserved structures were first studied in acid-prepared material from Lower Devonian limestones from Burrinjuck, NSW (White 1952). Later placoderm studies (e.g. Young 1980; Long & Young 1988; Goujet & Young 2004) demonstrated a unique eye muscle arrangement amongst jawed vertebrates, resembling living agnathans (Fritzsch et al 1990), with important phylogenetic implications for the origin of other major groups (Basden & Young 2001). BASDEN, A., YOUNG, G.C., COAXES, M., & RITCHIE, A. and2000. The most primitive osteichthyan braincase? iVa^z/r^ 403, 186-188. BASDEN, A. & YOUNG, G.C., 2001. A primitive actinopterygian neurocranium from the Early Devonian Taemas Formation, Burrinjuck area, New South Wales, Australia. Journal of Vertebrate Paleontology 21, 754-766. FRITZSCH,^ B., SONNTAG, R., DUBUC, R., OHTA, Y., & GRILLNER, S. 1990. Organization of the six motor nuclei innervating the ocular muscles in lamprey. Journal of Comparative Neurology 294, 491-506. GOUJET, D. & YOUNG, G.C., 2004. Placoderm anatomy and phylogeny: new insights. In Recent Advances in the Origin and Early Radiation of Vertebrates, ARRATIA, G., WILSON M.V.H., and Cloutier, R., eds., Verlag Dr. Friedrich Pfeil, Munchen, 109-126. LONG, J. A. & YOUNG, G.C., 1988. Acanthothoracid remains from the Early Devonian of New South Wales, including a complete sclerotic capsule and pelvic girdle. AAP Memoirs 7, 65-80. NEAL, H.V., 1918. The history of the eye muscles. Journal of Morphology 30, 433-453. WHITE, E.I., 1952. Austrahan Arthrodires. Bulletin of the British Museum (Natural History) Geology 1, 249-304. YOUNG, G.C., 1980. A new Early Devonian placoderm from New South Wales, Australia, with a discussion of placoderm phylogeny. Palaeontographica A 167, 10-76.
THE NEUROCRANIUM OF AN EARLY DEVONIAN ACANTHODIAN Martin D. Brazeau Subdepartment of Evolutionary Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18A SE 752-36, Uppsala, Sweden, martin.brazeau@ebc.uu.se Key words: Acanthodii, neurocranium, Devonian, phylogeny The study of early gnathostome interrelationships is mired by a paucity of endoskeletal data as this system was typically not mineralised in early taxa. For the acanthodians, a particularly diverse group of early gnathostomes, this problem is greatest as neurocrania are available from only a single taxon Acanthodes bronni. Acanthodes presents an osteichthyan-like neurocranium, supporting a Acanthodii + Osteichthyes sister-group relationship. However, this interpretation presupposes acanthodian monophyly. This auxiliary hypothesis has been challenged in recent years by the discovery of unexpected fm spine distributions in early chondrichthyans (Miller et al 2003) and osteichthyans (Zhu et al 1999). Still, the lack of 14
endoskeletal data from acanthodians leaves little positive evidence in support of alternative cladistic hypotheses. The first known neurocranium of an Early Devonian "climatiid" acanthodian is presented here along with an analysis testing current hypotheses of early gnathostome phylogeny. This neurocranium presents unexpected similarities with placoderm and early chondrichthyan neurocrania while bearing few points of resemblance with Acanthodes. In light of this, acanthodian systematics are reviewed in the broader context of early gnathostome interrelationships. MILLER, R.F.; CLOUTIER, R. & TURNER, S., 2003. The oldest articulated chondrichthyan from the Early Devonian period. Nature 425, 501-504. ZHU, M.; YU, X. & JANVIER, P., 1999. A primitive fossil fish sheds light on the origin of bony fishes. Nature 397, 607-610.
A STRANGE NEW EDENTULOUS GNATHOSTOME FISH FROM THE UPPER DEVONIAN GOGO FORMATION John A. Long Museum Victoria, PO Box 666, Melbourne, VIC 3001, Austraha, jlong@museum.vic.gov.au Key words: Devonian, vertebrate, gnathostome, acanthodian A cryptic new taxon of fish was discovered in 2005 from the Late Devonian Gogo Formation. The specimen initially looked much like an eel, without fins or body scales, but having thick bands of Wshaped somitic muscles preserved (as recently described in other Gogo fishes, Trinajstic et al 2006). It was carefully prepared by resin transfer method to reveal an intact set of jaws, braincase, visceral arches and a series of perichondral vertebral elements. In lacking fins, fin-spines and any form of scale cover, it is unlike any previous known Palaeozoic gnathostome. The braincase has dorsal, occipital and ventral units separated by fissures as in Acanthodes. In addition, the visceral arch pattern matches that of an acanthodiform acanthodian. The jaw articulation is not as complex as in Acanthodes but shows a comparable arrangement in the cotylus-articular arrangement. Meckel's cartilage and palatoquadrate are acanthodian-like. Whilst it is possible the specimen has suffered post-mortem damage by loss of outer integument and fins, this is unlikely as the fin-spines insert deeply into the axial musculature in acanthodians, and such areas were not damaged. Traces of a large, plate-like cuticle of skin, possibly formed by post-mortem disruption, are evident, suggesting the outer scale-less integument is wellpreserved, as is also seen by the clear lines defining the body shape. It is here suggested that the specimen represents the first ever record of the Class Acanthodii from Gogo. It is interpreted as a secondarily specialised form of substrate dwelling, filter-feeding eel-like acanthodiform, probably occupying a similar niche to certain reef-dwelling anguilliforms (Heterocongrinae, garden eels). TRINAJSTIC, K., MARSHALL, C., LONG, J. & BIFIELD, K., 2007. Exceptional preservation of nerve and muscle tissues in Late Devonian placoderm fish and their evolutionary implications. Biology Letters doil0.1098/rsbl 2006.0604.
CHONDRICHTHYAN FOSSILS FROM THE FAMENNIAN OF SOUTH AFRICA Robert W. Cess Bernard Price Institute (Palaeontology), School of Geosciences, University of Witwatersrand, Johannesburg, 2050, South Africa, robg@imaginet.co.za Key words: Chondrichthyes, Antarctilamna, Famennian, Witteberg A single black shale lens within the Upper Devonian, Famennian, Witpoort Formation (Witteberg Group, Cape Supergroup) of South Africa has yielded a fish fauna. This lens, within quartz arenites, is exposed in a road cutting near Grahamstown, and is interpreted as having been deposited in a coastal estuarine lagoon, on a barrier island dominated coastline (Hiller & Taylor 1992). Chondrichthyan fossils therein form part of a diverse fossil fauna, otherwise composed of placoderms, acanthodians, 15
actinopterygians, sarcopterygians and a lamprey (Gess 2001; Gess et al 2006; Gess & Hiller 1995; Hiller & Taylor 1992; Long et al 1997). Initial finds of a semi-articulated partial chondrichthyan skeleton and an additional damaged fm-spine provided the type material for Plesioselachus macracanthus (Anderson et al 1999). Substantially more chondrichthyan material has subsequently been collected, including a number of Plesioselachus elements. These include a complete dorsal fm spine and several scapulocoracoids, which allow for a reinterpretation of Plesioselachus. It is shown to be a primitive shark with a long shallowly inserted dorsal fin spine, lacking a basal element, with costae extending posteriorly to a broad basal opening. The coracoid has a backward facing articular condyle and the caudal fm is heterocercal. Remains of Antarctilamna, the pan Gondwanan shark, formally thought of as a mid-Devonian genus, have also been excavated. New details of the mandibular arch are revealed in a disarticulated association of elements that also includes ceratohyals, a fm spine, and teeth. Very little difference is evident between this and mid Devonian species. A soft body impression of a juvenile, which could be that of Plesioselachus, has two dorsal fins, with a large spine anterior to only the first one. ANDERSON, M.E., LONG, J.A., GESS, R.W., 8c HILLER, N., 1999. An unusual new fossil shark (Pisces: Chondrichthyes) from the Late Devonian of South Africa. Records of the Western Australian Museum 57, 151-156. GESS, R.W., 2001. A new species of Diplacanthus from the Late Devonian (Famennian) of South Africa. Annales de Paleontologie 87, 49-60. GESS, R.W., COATES, M.I. & RUBIDGE, B.S., 2006. A lamprey from the Devonian period of South Africa. Nature 443, 981-984. GESS, R.W. & HILLER, N., 1995. A preliminary catalogue of fossil algal, plant, arthropod, and fish remains from a Late Devonian black shale near Grahamstown, South Africa. Annals of the Cape Provincial Museums (Natural History) 19, 225-304. HILLER, N. & TAYLOR, F.F., 1992. Late Devonian shore line changes: an analysis of Witteberg Group stratigraphy in the Grahamstown area. South African Journal of Geology 95, 203-212. LONG, J.A., ANDERSON, M.E., GESS, R.W. & HILLER, N., 1997. New placoderm fishes from the Late Devonian of South Africa. Journal of Vertebrate Palaeontology 17, 253-268.
A REDESCRIPTION OF THE DERMAL OSTEOLOGY OF THE BASAL ACTINOPTERYGIAN msn MOYTHOMASIA DURGARINGA Brian Choo Department of Earth and Marine Sciences, Australian National University, Canberra, ACT 0200, Australia; Museum Victoria, GPO Box 666, Melbourne, VIC 3001, Australia, bchoo@museum. vie. gov. au Key words: Moythomasia, Gogo Formation, Actinopterygii, fish Among numerous outstanding fossil discoveries, the famous Late Devonian (lower Frasnian) Gogo fish fauna has produced the most complete Palaeozoic examples of the Actinopterygii, or ray-finned fish, in the world. Moythomasia durgaringa is one of two of the currently described taxa of actinopterygian from this lagerstatten along with "M/wza" toombsi (currently a preoccupied genus). It is known from muhiple articulated specimens displaying the exceptional dermal and perichondral preservation characteristic of Gogo fossils. Despite this, aspects of the dermal osteology of Moythomasia durgaringa have only received a cursory treatment in the literature and have never been fully illustrated. As yet the only scientific reconstruction of the dermal elements in articulation consists of a simple diagram of the head in lateral view. While both of the currently described Gogo ray-fins have featured in most phyletic studies of basal actinopterygians, key characters of M. durgaringa have been omitted, especially those pertaining to the postcrania. 16
The July 2005 field expedition to the Gogo Formation acquired multiple complete specimens of Moythomasia durgaringa. This has allowed for a revised examination of the dermal bones of this fish as well as the first rigorous full-body reconstruction of this important taxon. The animal differs significantly from well-known reconstructions of Moythomasia based on European material with regards to cranial dermal layout and proportions of the body.
A NEW HOLODIPTERID FROM THE LATE DEVONIAN GOGO FORMATION, WESTERN AUSTRALIA Alice M. Clement Museum Victoria, PC Box 666, Melbourne, VIC 3001, Australia, aclement@museum.vic.gov.au Key words: Gogo Formation, Devonian, holodipterid, postcranial The Gogo Formation of North Western Australia (Frasnian) has historically yielded many specimens from a diverse range of Devonian taxa (Long 2006). Many of which are exceptionally preserved allowing us to gather detailed anatomical information about the fish of the Gogo ecosystem (Trinajstic et al 2007). A new holodipterid lungfish discovered during the 2005 Museum Victoria Gogo expedition is described. After careful acid preparation, a heavily ossified mandible and palate showing a unique dentition has been revealed. Also of note are two near complete shoulder girdles and sections of the cheek and skull roof There has been no evidence of any preserved braincase, possibly due to it being unossified. The specimen differs from other holodipterids in its broad, crushing dentition, lack of prominent teeth, and in aspects of the parasphenoid. Further preparation is hoping to reveal vertebrae, fm detail and possibly information of the pelvic girdle. Post-cranial material is relatively rare, so this near complete holodipterid specimen will contribute significantly to our understanding of the anatomy and morphology of these fish. With this new information of both cranial and postcranial characters, I aim to complete a cladistic analysis to contribute further to our understanding of interrelationships and intra-relationships of the Dipnoi. LONG, J., 2006. Swimming in Stone - The Amazing Gogo Fishes of the Kimberley. Fremantle Arts Centre Press, Perth, 320pp. TRINAJSTIC, K., MARSHALL, C., LONG, J. & BIFIELD, K. 2007. Exceptional preservation of nerve and muscle tissues in Late Devonian placoderm fish and their evolutionary implications Biology Letters doil0.1098/rsbl 2006.0604
A NEW TOOTH-FLATED DIPNOAN FROM THE MIDDLE DEVONIAN OF YUNNAN, CHINA, AND ITS PHYLOGENETIC RELATIONSHIPS Tuo Qiao^'^ & Min Zhu ^ ^Institute of Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, People's Republic of China; biyaoqt@hotmaii.com. ^ Graduate School of the Chinese Academy of Sciences, Beijing 100039, People's Republic of China. Key words: Dipnoan, Phylogeny, Devonian, China A new genus of dipnoans (Sarcopterygii, Osteichthyes) with tooth plates, is described from the Qujing Formation (late Eifelian, Middle Devonian) of Zhaotong, Yunnan, China. The referred specimens include a nearly complete skull roof, several cheek bones, submandibular bones, gular bones, some detached skull roof bones and several tooth plates. The new genus manifests many DipterusAikQ features in the skull roof pattern such as: elongated E-bones, a long prepineal length, I-bones separated by B-bone, and one small D-bone. However, the tooth plates are distinguishable from those of Dipferus : cosmine absent near the midline; number of tooth rows less than 10; tubercles present in furrows between tooth rows; angle between the first and last tooth row less than 90°; medial flange of the pterygoid strongly reduced. As for the relationship of dipnoans, there are two different phylogenetic methods: the functional analysis without parsimony (Campbell and Barwick 1990) and the systematic analysis with parsimony (Schultze and Marshall 1993; Schultze 2001; Ahlberg 2006). 17
We present a phylogenetic analysis of Devonian dipnoans with parsimony, and show that all of the Early Devonian dipnoans are on a lower level than Dipterus except for Sorbitorhynchus and the new genus is more derived than Dipterus. As Sorbitorhynchus was found from the Emsian (Lower Devonian), we may deduce that Dipterus had diversified before the Middle Devonian. The result also suggests the apical position of all Late Devonian dipnoans. AHLBERG, P.E., SMITH, M.M., & JOHANSON, Z., 2006. Developmental plasticity and disparity in early dipnoan (lungfish) dentitions. Evolution & Development 8, 331-349. CAMPBELL, K.S.W. & BARWICK R.E., 1990. Paleozoic dipnoan phylogeny: functional complexes and evolution without parsimony. Paleobiology 16, 143-169. SCHULTZE, H.P., 2001. Melanognathus, a primitive dipnoan from the Lower Devonian of the Canadian Arctic and the interrelationships of Devonian dipnoans. Journal of Vertebrate Paleontology 21,781-794. SCHULTZE, H.P. & MARSHALL C.R., 1993. Contrasting the use of functional complexes and isolated characters in lungfish evolution. Memoirs of the Association of Australasian Palaeontologists 15,211-224.
NEW MIDDLE DEVONIAN OSTEOLEPID MATERIAL (LOBE-FINNED FISH) FROM HATCHERY CREEK, NEW SOUTH WALES. James R. Hunt Department of Earth and Marine Sciences, Australian National University, Canberra, ACT 0200, Australia, j ames .hunt @ems. anu.edu. au Key words: Middle Devonian, Osteolepidida, Australia. The Hatchery Creek Formation (?Eifelian) is a sequence of conglomerate, sandstone and mudstone 2.8 km thick containing fish, plant and arthropod material. The formation overlies the Early Devonian (Emsian) limestones at Wee Jasper, NSW. Young and Gorter (1981) described nine fish species and Hunt (2005) identified additional actinolepid placoderms and osteolepids. Young and Gorter (1981) tentatively assigned the osteolepiform Gyroptychius? australis (characterised by an extremely short and broad frontoethmoidal shield) to the Scottish genus Gyroptychius as described by Jarvik (1948). Chang and Zhu (1993) suggested that Kenichthys from China was very similar in the size and proportions of the frontoethmoidal shield, along with grooved nares. Kenichthys has been placed as the most primitive tetrapodomorph in the phylogeny of Ahlberg and Johanson (1998). My research on the upper -1.3 km sequence identified 19 sedimentary cycles (sandstone/mudstone) above the lower 1500m of conglomerates/sandstone. Fish were found in 11 cycles, including evidence of a second osteolepid. New material includes many lower jaws, three fronto-ethmoidal shields, four parietal shields, three cheek units, four jugals and four suboperculars. Two different morphologies will be illustrated for this material. The new data shows the cheek was short and broad in Gyroptychius? australis with a configuration not seen in other osteolepids. The lower jaw shows primitive features (pits along the ventral surface) as in the basal sarcopterygians Youngolepis and Psarolepis from China, but lacking in Kenichthys (see Zhu & Yu, 2004). Gyroptychius? australis may in fact be more primitive than Kenichthys, and will be described as a new genus. AHLBERG, P. & JOHANSON, Z., 1998. Osteolepiforms and the ancestory of tetrapods. Nature, 395, 792-794. CHANG, M. & ZHU, M., 1993. A new Middle Devonian osteolepidid from Qujing, Yunnan. AAP Memoirs 15, 183-198. HUNT, J., 2005. An Examination of Stratigraphy and Vertebrate Fish Fauna of the Middle Devonian Age from the Hatchery Creek Formation, Wee Jasper, New South Wales, Australia. B.Sc Honours Thesis, Dept. Earth & Marine Science, ANU, 112pp. JARVIK, E., 1948. On the morphology and taxonomy of the Middle Devonian osteolepid fishes of Scotland. Kungliga Svenska Vetenskakademiens Handlingar (3) 25, 1-301.
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YOUNG, G.C. & GORTER, J.D., 1981. A new fish fauna of Middle Devonian age from the TaemasAVee Jasper region of New South Wales. Bureau of Mineral Resources Geology & Geophysics, Bulletin 209, 83-147. ZHU, M. & YU, X., 2004. Lower jaw character transitions among major sarcopterygian groups - a survey based on new materials from Yunnan, China. In Recent Advances in the Origin and Early radiation of Vertebrates. G. ARRATIA et aL, eds., Verlag Dr. Friedrich Pfeil, Miinchen, 271-289.
LATE DEVONIAN SARCOPTERYGIANS FROM NINGXIA, NORTHWESTERN CHINA, AND THEIR BIOGEOGRAPHIC BEARING Min Zhu Institute of Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, People's Republic of China; zhumin@i vpp,acxn. Key words: Sarcopterygii, Biogeography, Devonian, China The Middle Palaeozoic vertebrates of China are mainly distributed in three major blocks of China, the South China (Yangtze and Cathaysian). North China and Tarim blocks. Recently, abundant fossil remains including a Devonian tetrapod have been found from the Late Devonian Remigolepis-hQaring deposits (Famennian) of Zhongning, Ningxia, which might be referred to the North China Block based on the stratigraphic syntheses and the characteristic of geological evolution. Sinostega pani represents the first discovery of a Devonian tetrapod from Asia, substantially extending the geographic range of these animals. From the same site and horizons were recovered new sarcopterygian (lobe-finned) fossils including at least two new tetrapodomorph fishes. One new form is suggestive of tristichopterids in its skull-roof pattern and the absence of cosmine, but differs in possessing rhombic scales, and a row of large teeth on the coronoids in addition to a marginal denticulate coronoid band and coronoid fangs. A preliminary phylogenetic analysis places this new form, the tristichopterids, and the lineage of elpistostegids + tetrapods in an unresolved trichotomy. The new form represents the first tetrapodomorph fish at the grade of tristichopterids or elpistostegids found from Asia, thus providing new evidence for the character acquisition of crownward tetrapodomorphs and bearing the biogeographic significance. The collection under study also includes a large tetrapodomorph fish with the head articulating with the postcranial skeleton, and other unidentified sarcopterygian materials, indicating a fairly diversified sarcopterygian fauna, that dates from the Late Devonian period.
NEW IDEAS ON SOME TRISTICHOPTERIDS (OSTEOLEPIFORM LOBE-FINNED FISHES) FROM THE LATE DEVONIAN OF AUSTRALIA Gavin C. Young Department of Earth & Marine Sciences, ANU, Canberra, ACT 0200, Australia, gyoung@ems.anu.edu.au Key words: tetrapodomorph morphology phylogeny biogeography Two large tristichopterids are known from excellent articulated material at the Canowindra fossil fish locality (Frasnian) in central NSW: Mandageria Johanson & Ahlberg (1997) and Cabonnichthys Ahlberg & Johanson (1997). A slightly older (?Givetian) very large tristichopterid is Notorhizodon Young et al. (1992) from the Aztec fauna of Antarctica. Eusthenodon Jarvik (1952) is another large tristichopterid, first described from the Famennian of East Greenland, where it is associated with tetrapods (Ichthyostega, Acanthostega). An Australian species of Eusthenodon occurs in the Famennian Hunter Siltstone near Grenfell, NSW (Johanson & Ritchie 2000); another 'large undescribed tristichopterid assignable to Eusthenodon' occurs in the Famennian Worange Point Formation on the coast south of Eden, NSW (Ahlberg et al 2001, p. 9). Ahlberg & Johanson (1997, fig. 16) assessed the relationships of the Canowindra tristichopterids as {Cabonnichthys {Mandageria {Eusthenodon))), the last two sharing the unique skull character of parietal separating the intertemporal and posterior supraorbital. More basal tristichopterids on their phylogeny {Tristichopterus, Eusthenopteron, Jarvikina, Platycephalichthys) are all Northern Hemisphere forms, supporting the idea that the group originated in Laurussia, reaching 19
Gondwana probably during 'Great Devonian Faunal Interchange' near the Frasnian-Famennian boundary. However some new evidence from structure of the palate and scale morphology suggests an alternative phylogeny, with an endemic Gondwanan clade comprising at least three members: Cabonnichthys and Mandageria from Canowindra, and 'Eusthenodon' from Eden. A newly recognised distinctive isolated scale from the Antarctic Aztec assemblage is very similar to the Canowindra scales. Biogeographically, this raises the possibility of a Gondwana origin for tristichopterids. AHLBERG, P.E. & JOHANSON, Z., 1997. Second tristichopterid (Sarcopterygii, Osteolepiformes) from the Upper Devonian of Canowindra, New South Wales, Australia, and the phylogeny of the Tristichopteridae. Journal of Vertebrate Paleontology 17, 653-673. AHLBERG, P.E., JOHANSON, Z. & DAESCHLER, E.B., 2001. The Late Devonian lungfish Soederberghia (Sarcopterygii, Dipnoi) from Australia and North America, and its biogeographical implications. Journal of Vertebrate Paleontology 21, 1-12. JARVIK, E., 1952. On the fish-like tail in the ichthyostegid stegocephalians with descriptions of a new stegocephalian and a new crossopterygian from the Upper Devonian of East Greenland. Meddelelser om Gronland 114, 1-90. JOHANSON, Z. & AHLBERG, P.E., 1997. A new tristichopterid (Osteolepiformes: Sarcopterygii) from the Mandagery Sandstone (Late Devonian, Famennian) near Canowindra, NSW. Transactions of the Royal Society ofEdinburgh: Earth Sciences 88, 39-68. JOHANSON, Z. & RITCHIE, A., 2000. Rhipidistians (Sarcopterygii) from the Hunter Siltstone (Late Famennian) near Grenfell, NSW, Australia. Mitteilungen aus dem Museum fur Naturkunde in Berlin, Geowissenschaftliche Reihe 3, 111-136. YOUNG, G.C., LONG, J.A., & RITCHIE, A., 1992. Crossopterygian fishes from the Devonian of Antarctica: systematics, relationships and biogeographic significance. Records of the Australian Museum, Supplement 14, 1-77. NEW DESCRIPTION AND THE PHYLOGENY OF THE TETRAPODOMORPH FISH MARSDENICHTHYS LONGIOCCIPITUS FROM MT. HOWITT, VICTORIA. Tim Holland School of Geosciences, Monash University, Clayton, VIC 3800; Museum Victoria, PO Box 666, Melbourne, VIC 3001, Australia, tholland@museum.vic.gov.au Key words: Marsdenicthys, Mt. Howitt, Tetrapodomorpha. Amongst the osteichthyian fauna described from the Givetian-Frasnian mudstone of Mt. Howitt, Victoria, the phylogentic position of Marsdenichthys remains a contentious issue. First described from two incomplete specimens by Dr. John Long in 1985, Marsdenichthys was initially placed as the most basal member of the Tristichopteridae, based on the presence of rounded scales with a median boss. This assignment has since become uncertain, as many other basal tetrapodomorph fish have been shown to exhibit similar scale morphology, including rhizodontids, and some former constituents of the 'Osteolepiformes', such as Canowindra, Medoevia and Rhizodopsis. Marsdenichthys also displays several other characters shared by basal tetrapdomorph fish, including longer postparietal relative to parietal bones and the presence of extratemporal bones This paper presents significant new information from two new specimens of Marsdenichthys from Mt. Howitt. Morphology from the check and the palate are described for the first time in Marsdenichthys, exhibiting a mixture of pleisomorphic and unique features. Scale morphology is compared to other tetrapodomorph fish taxa and shown to be most similar to Rhizodopsis. Preliminary results from a cladistical analysis are also discussed, shedding new light on the place of Marsdenichthys within the Tetrapodomorpha. LONG, J., 1985. The structure and relationships of a new osteolepiform fish from the Late Devonian of Victoria, Australia. Alcheringa 9, 1-22.
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A NEW GENUS OF THE TETRAPODOMORPHA FROM THE POSONGCHONG FORMATION (PRAGIAN, EARLY DEVONIAN) OF ZHAOTONG, YUNNAN, CHINA Jing Lu^'^ & Min Zhu^ Institute of Palaeontology and Palaeoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, People's Republic of China; lujingv@:ivpp.ac.cn. ^ Graduate School of the Chinese Academy of Sciences Beijing 100039, People's Republic of China. IT
Key words: Tetrapodomorpha, phylogeny, Pragian, China A new genus and species of the Tetrapodomorpha is described from the Posongchong Formation (Pragian, Early Devonian) of Zhaotong, Yunnan, China. The new form exhibits many 'osteolepidid' features in the head, e.g. the processus dermintermedius, the group of pores on dermal bones, the same pattern of neurovascular openings on the lateral wall of endocranium, the flat parasymphsial dental plate, and the dentary teeth reaching the anterior end of the jaw. In other aspects, it is quite similar to Youngolepis and porolepiforms in the presence of two external nasal openings, paired intemasal pits, and the elongate parasphenoid separating two vomers. It also shares with Youngolepis, Kenichthys and Thursius wudingensis an independent premaxillary with infraorbital sensory canal following its suture, a compound squamosal + quadratojual + preopercular bone with three pits. The new form is unique in its largest orbital notch compared with the whole length of the parietal shield and the most anteriorly situated pineal foramen among 'osteolepidids'. Besides, it has an obvious parasymphysial tusk and a socket for replacement of the tusk, as in some basal tetrapods. Different from the 'lateral tooth pavement' in Youngolepis, Kenichthys and other 'osteolepidids', there is only a single row of denticles on the lateral portion of the coronoids in the new form. The phylogenetic analysis suggests the basal position of the new form among the Tetrapodomorpha. As the earliest known member of the Tetrapodomorpha, the new form in this study provides significant data bearing on the origin of the Tetrapodomorpha and helps in the study of the divergence of Dipnomorpha and Tetrapodomorpha.
THE BRANCHIAL SKELETON OF TIKTAALIKROSEAE ELPISTOSTEGALIA)
(TETRAPODOMORPHA:
Jason Philip Downs\ Edward B. Daeschler\ Neil H. Shubin^, and Parish A. Jenkins Jr^ ^Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, PA 19103, USA, downs@ansp.org; ^University of Chicago, Department of Organismal Biology and Anatomy, 1027 E. 57th Street, Chicago, Illinois 60637, USA; ^Harvard University, Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, 26 Oxford Street, Cambridge, Massachusetts 02138, USA Key words: Tetrapodomorpha, Elpistostegalia, respiration, branchial skeleton Gill-breathing vertebrates use an apparatus formed of head, hyoid, branchial skeleton, and pectoral girdle to regulate pressure in the oropharyngeal and parabranchial cavities. Differential pressure among these cavities, the lungs (if present), and the surrounding environment is the primary driver of suction feeding, lung ventilation, and gill respiration in these organisms. The vertebrate transition to land and the evolution of a thoracic aspiration pump were associated with morphological innovations; these include the decoupling of the pectoral girdle and head skeleton, loss of the opercular bones, reduction of the ossified branchial skeleton, and strengthening of the ribs. The phylogenetic position and exceptional preservation of Tiktaalik roseae reveals an intermediate condition in the vertebrate transition to a terrestrial respiratory mechanism. The branchial skeleton of T. roseae preserves four arches in addition to the hyoid. The hyoid and first three arches articulate ventrally with two basibranchials; the fourth arch articulates with the third. The robust ceratobranchials have deep grooves for the branchial arteries. Whether breathing air, water, or both, the branchial anatomy of T. roseae indicates that the primitive oropharyngeal force pump was functioning in the presence of morphological innovations associated with a changing respiratory mechanism. The 21
unique combination of primitive and derived features in T. roseae presents an opportunity to deconstruct the oropharyngeal and thoracic pumps of vertebrates into a suite of evolving characters.
THE SEDIMENTOLOGY OF THE MID-VISEAN TETRAPOD LOCALITY AT DUCABROOK, CENTRAL QUEENSLAND: DEPOSITIONAL ENVIRONMENT AND PALAEOBIOGEOGRAPY Kate Parker^ and John Webb^ Department of Zoology^ and Department of Environmental Geoscience^, La Trobe University, Melbourne, VIC 3086, Australia, k.parker@latrobe.edu.au Key words: Visean, Tetrapod, Sedimentology, Palaeobiogeography The mid Visean vertebrate site at Ducabrook in central Queensland is considered to be of significance due to the rich fish and tetrapod fauna it comprises. Ossinodus is the only recorded stem tetrapod body fossil from the Southern Hemisphere during the Upper Devonian to Lower Carboniferous, a crucial period in tetrapod evolution (Warren & Turner 2004). Stem-tetrapods have often been perceived as inhabiting freshwater environments, yet the sedimentology of some tetrapod-bearing sites in the Northern Hemisphere have been interpreted to be otherwise. The tetrapod-bearing unit at Ducabrook is a thin sandstone and conglomeratic unit amongst thick siltstones interbedded with thinner sandstones, minor oolitic limestones and conglomerates. Overall five facies are recognized, representing braid river and flood plain, and inner and outer estuarine environments. The depositional environment of the tetrapodbearing unit at Ducabrook indicates that the fish and tetrapod were rapidly deposited by storm-induced flooding onto an estuarine channel floor. An estuarine habitat for tetrapods may explain the distribution of stem-tetrapods across palaeocontinents with migration between them occurring along the shallow continental shelves. WARREN, A. & TURNER, S., 2004. The first stem tetrapod from the Lower Carboniferous of Gondwana. Palaeontology A1, 151-184.
THE AUSTRALIAN STEM TETRAPOD OSSINODUS PUERIV^A^^.^ AND TURNER, 2004 AND THE DISTRIBUTION OF SENSORY CANALS IN EARLY TETRAPODS Anne Warren Department of Zoology, La Trobe University, Melbourne, VIC 3086, Australia, a. waiTcn@ 1 atrobe.edu.au Key words: Stem tetrapod. Early Carboniferous, Queensland, sensory canals Disarticulated material of the stem tetrapod, Ossinodus pueri has been collected from the Ducabrook Formation of the Drummond Basin, Queensland, since 1995 (Warren & Turner 2004). New material, including a half skull, was found in 2004 filling gaps in knowledge of the overall anatomy of O. pueri. Despite the apparent disparity in the skull morphology and body proportions shown by this material, phylogenetic analysis still places O. pueri in the Whatcheeridae, a clade otherwise containing only Pederpes finneyi from Scotland (Clack & Finney 2005) and Whatcheeria deltae, from Iowa (Lombard & Bolt 1995).The new cranial material provides insight into the sensory canal system of early tetrapods, suggesting that absence of pores or open canals on the outer surface of the dermal bones of the skull does not necessarily mean that this sensory system was absent. Hence the terrestrial or aquatic habitat occupied by a particular tetrapod should not be inferred from the apparent absence or presence of sensory pores or canals. CLACK, J.A. & FINNEY S.M., 2005. Pederpes finneyae, an articulated tetrapod from the Toumaisian of western Scotland. Journal of Systematic Palaeontology 2, 311-346. LOMBARD, E.R., & BOLT J.R., 1995. A new primitive tetrapod, Whatcheria deltae, from the Lower Carboniferous of Iowa. Palaeontology 38, 471-494.
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WARREN, A.A., & TURNER S., 2004. The first stem tetrapod from the Early Carboniferous of Gondwana. Palaeontology 47, 1-34.
A PALEOCENE DEEP-WATER SHARK FAUNA FROM THE SOUTHWEST PACIFIC A1 Mannering and Norton Hiller Canterbury Museum, Rolleston Avenue, Christchurch, New Zealand, nhiller@canterburymuseum.com Key words: Elasmobranchs, Paleocene, Waipara Greensand, New Zealand Apart from the enigmatic cnidarian, Waiparaconus Buckeridge, 1983 and the remains of the early penguin, Waimanu Jones, Ando & Fordyce, 2006, the Waipara Greensand of North Canterbury, New Zealand is not noted for its fossils. However, careful searching of exposures along the banks of the Waipara River has produced several hundred isolated shark teeth. Nannofossil dating of the sediment gives a Danian to Selandian age for the majority of the specimens. The fauna includes at least 14 elasmobranch genera, of which several are new records for the New Zealand fossil biota. Representatives of the living frill sharks, cow sharks, gulper sharks, dogfish, kitefm sharks, sand tigers and goblin sharks are present in the fauna. In addition, a number of extinct genera, such as Notidanodon, Sphenodus and Paraorthocodus, are remnants of the Cretaceous fauna. This Waipara Greensand fauna allows insight into the shark species present in the southwest Pacific during the Paleocene and adds to the knowledge of shark faunas of this age world wide. Comparison with extant species belonging to several of the genera present suggests that the fauna is a deep water one, probably typical of the outer continental shelf to upper continental slope. This conclusion is apparently at odds with the interpretation of the Waipara Greensand as having been deposited in a shallow marine setting under conditions of very slow sedimentation (Browne & Field 1985) and requires further investigation. BROWNE, G.H. & FIELD, B.D., 1985. The lithostratigraphy of Late Cretaceous to Early Pleistocene rocks of northern Canterbury, New Zealand. New Zealand Geological Survey Record 6, 63pp.
RECENT DISCOVERIES FROM THE CRETACEOUS AND PALEOCENE OF THE RUKWA RIFT BASIN, TANZANIA, INCLUDING NEW RECORDS OF NEOCERATODUS AND PROTOPTERUS (DIPNOI) Michael Gottfried\ Patrick 0'Connor^ Nancy Stevens^ Eric Roberts^ and Sifa Ngasala"^ ^Geological Sciences & Museum, Michigan State University, East Lansing, MI 48824-1045, USA; gottiTie@msu.edu; ^Department of Biomedical Sciences, Ohio University, Athens, Ohio, 45701, USA; ^School of Geosciences, University of the Witwatersrand, Private Bag 3, 2050 Wits, Johannesburg, South Africa; '^Department of Geological Sciences, Michigan State University, East Lansing, Michigan, 48824, USA Key words: Tanzania, Cretaceous, Paleogene, Lungfish Our understanding of Gondwanan vertebrate diversity and biogeography during the Cretaceous and early Cenozoic has greatly improved in recent decades, but sub-equatorial African data from these crucial intervals still lag behind discoveries from other parts of Gondw^ana. We are bridging this gap by developing diverse Cretaceous and Paleogene vertebrate faunas from Red Sandstone Group (RSG) exposures in the Rukwa Rift Basin (RRB) of western Tanzania. Field exploration has resulted in the discovery of representatives of numerous vertebrate groups; Cretaceous (RSG Unit I) sites preserve fishes (osteoglossomorphs, and lungfish [below]), turtles, crocodylomorphs, theropod and sauropod dinosaurs, and a gondwanatherian mammal. Paleogene (RSG Unit II) sites from the RRB have produced fishes (polypterids, siluriforms, and lungfish [below]), abundant frogs, macroscelideans (elephant shrews), and an array of phiomorph rodents. 23
Prior to these recent expeditions, Mesozoic lungfishes were not known from Tanzania. A Cretaceous (Unit I) site in the RSG has yielded a well-preserved ceratodontid toothplate, with a morphology consistent with fossil African and fossil and Recent Australian Neoceratodus. This is the first Mesozoic lungfish from Tanzania and extends the paleo-distribution of Neoceratodus into the southwestern end of the Rift Valley. In addition, two Protopterus toothplates have been recovered from a Paleogene (Unit II; likely Oligocene) horizon within the RSG, adding a new fossil datum to the African record of this still-extant genus, and supporting an interpretation of warm and seasonally arid conditions in this sector of the Rift Valley during the Paleogene.
General sessions NEW FINDS FROM THE TASMANIAN TRIASSIC Anne Warren^ and Andrew Rozefelds^ ^Department of Zoology, La Trobe University, Melbourne, VIC 3086, Australia, a.warren@latrobe.edu.au; ^Tasmanian Museum and Art Gallery, GPO Box 1164, Hobart, TAS 7001, Australia Key words: Early Triassic, Temnospondyli, Dicynodontia, A new site on the Tasman Peninsula has yielded a fauna of Early Triassic age from the Knocklofty Formation of the Upper Parmeener Supergroup. The fossils come from two horizons within a micaceous siltstone: a horizon yielding small bones, especially of actinopterygians, and a slightly younger horizon with relatively abundant skulls and some postcranial material of a small temnospondyl. A granular sandstone overlying the above contained two bones of a larger tetrapod. Some fifteen skulls and mandibles of a short skulled temnospondyl initially have been identified as a new taxon of Brachyopidae from the Mesozoic clade of temnospondyls, the Stereospondyh. This is the largest known accumulation of brachyopid skulls, and the only site with multiple associated mandibles and postcranial material. An articulated series of twenty six vertebral centra are diplospondylous spools, a morphology not elsewhere associated with brachyopids, but with the Tupilakosauridae, a rare taxon from a predominantly Laurasian clade, the Dvinosauria. A large partial maxilla bearing a tooth, and a probable radius are not from the Temnospondyli and may constitute the first record in Tasmania of the Dicynodontia, a taxon that is the commonest component of the fauna in most non-Australian Early Triassic localities, but represented in Australia only by a few scraps from the Early Triassic Arcadia formation of Queensland, and a single Early Cretaceous maxillary tusk (Thulbom & Turner, 2002). THULBORN, T., & TURNER, S. 2002. The last dicynodont: an Australian Cretaceous relict. Proceedings of the Royal Society of London B 270, 985-993.
BIOMECHANICS OF RHACHITOMOUS VERTEBRAE IN EARLY TETRAPODS Kat Pawley and Steven W. Salisbury ^^ ^Department of Zoology, La Trobe University, VIC 3086, AustraUa, k.pawley@latrobe.cdii.aii; ^Current address: do P.O. Box 71, Bundoora, Victoria 3083 Australia; ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia; Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA Key words: Early tetrapod, vertebral centrum, biomechanics, locomotion Rhachitomous vertebrae are common in early tetrapods, consisting of separate w^edge shaped intercentra and pleurocentra, not fused to the neural arch. Much of the internal area is unossified, presumably having been filled by soft tissues. The biomechanics of rhachitomous vertebrae are reinterpreted using anatomical 24
and biomechanical evidence from extant taxa. Extant phylogenetic bracketing (Bryant & Russell, 1992) used Osteichthyes and limbed extant lower tetrapods (Urodela, Squamata). Recent soft tissue reconstructions indicate that rhachitomous centra are similar to those of extant lower vertebrates, except that they remain largely cartilaginous, which may have facilitated a greater capacity for load transmission and absorption between adjoining vertebrae. Previous biomechanical studies on salamanders and lizards indicate that stabilization of the trunk against the diagonal torsional forces generated during locomotor activity is a significant mechanical component of terrestrial locomotion. In both groups, stabilisation of the axial skeleton is achieved dorsally by bone-lock at the zygapophysial articulations, and ventrally by the action of differentiated hypaxial muscles. Differentiated hypaxial muscles are absent in fish, and were most likely also absent in the earliest tetrapods to venture onto land. In early tetrapods with rhachitomous vertebrae, we propose that zygapophysial articulations restricted axial rotation around the spinal cord, and that the configuration of the cartilage in the centra additionally functioned to stabilise the vertebral column by absorbing and distributing the torsional forces generated during terrestrial locomotion. As such, the acquisition of rhachitomous vertebra represents a key phase in the evolution of the terrestrial locomotor capabilities of early tetrapods. BRYANT, H.N. & RUSSELL, A.P., 1992. The role of phylogenetic analysis in the inference of unpreserved attributes of extinct taxa. Philosophical Transactions of the Royal Society B: Biological Sciences AOS A SHORT HISTORY OF VICTORIAN POLAR DINOSAURS AND OTHER VERTEBRATES David Pickering^ and Lesley KooF ^Museum Victoria, GPO Box 666, Melbourne, VIC 3001, Australia, dpick@museum.vic.Rov.au; ^School of Geosciences, Monash University, VIC 3168, Australia Key words: Australia, Cretaceous, Dinosaurs, Vertebrates. In 1903 the first Australian dinosaur bone was found at Eagle's Nest, near Inverloch on the Victorian south coast. Since then thousands of bones and teeth from dinosaurs and other vertebrates have been recovered from Early Cretaceous (Aptian/Albian) sediments. Most of the fossils were extracted from Dinosaur Cove in the Otways (Albian) between 1984 and 1994, and from Inverloch in the Strzeleckis (Aptian) from 1994 to the present day. The dominant group of dinosaurs in Victoria are the hypsilophodontids, which is different to elsewhere in the world where they make up only a small percentage of the dinosaur fauna. Apart from the hypsilophodontids there are a number of other dinosaur taxa represented, including small and medium theropods, omithomimids, ankylosaurs, and a neoceratopsian. Non-dinosaurian vertebrates include temnospondyls, plesiosaurs, turtles, pterosaurs, crocodiles, fish and at least four families of mammals. New localities such as "Eric the Crayfish Bay" site near Cape Otway have produced exciting discoveries in the last twelve months and ongoing prospecting is expected to reveal many more. THE VERTEBRATE FAUNA OF THE CRETACEOUS-PALEOGENE TAKATIKA GRIT, CHATHAM ISLANDS, NEW ZEALAND: INSIGHTS INTO A NEW TERRESTRIAL AND MARINE TETRAPOD ASSEMBLAGE ON THE EDGE OF AN AUSTRAL VOLCANO Christopher P. Consoli and Jeffery D. Stilwell School of Geosciences, Building 28, Monash University, VIC 3800 Australia, chrisxxinsoli^xi;sci.iTioiiash.edu.au
Key words: Reptilia, Aves, Cretaceous-Paleogene, Zealandia The first comprehensive study of a succinct Cretaceous-Paleogene succession on the Chatham Islands (CI) has provided important insights into the marine and terrestrial tetrapod communities that inhabited 25
Zealandia and the oceans which surrounded the micro-continent. The specimens were derived from the Takatika Grit, which was deposited in shallow marine conditions, and comprises glauconitic quartzofeldspathic grit and abundant phosphorite nodules. It is one of few formations in the Southern Hemisphere which spans the latest Cretaceous and into the early Paleogene with preserved macrofossil remains. Post-cranial marine reptile material, including mosasaurine mosasaurs and elasmosaurid plesiosaurs have been identified and described for the first time. It adds to the emerging recognition that in the Late Cretaceous in the Southern Hemisphere there is a distinct Austral pelagic fauna comprising largely elasmosaurs and a very diverse assemblage of mosasaurs, dominated by the mosasaurines. The discovery of both articulated and associated remains of avian and non-avian dinosaurs is the first known of these terrestrial animals from this region. Preliminary studies indicate that there are two groups of birds and also several groups of theropod dinosaurs. Other important fossils comprise new records of fishes, ammonites, nautiloids, gastropods, sponges, and plant matter. These findings have not only enhanced greatly our knowledge of ancient animal and plant life in the NZ-CI region at the end of the Mesozoic Era, but have shown that terrestrial organisms such as dinosaurs and ancestors of modem birds existed on Zealandia for millions of years following the separation of the NZ-CI region from Antarctica ca.80-85 m.y.a. NEW PTEROSAUR FOSSILS FROM THE EARLY CRETACEOUS (APTIAN-ALBIAN) OF WESTERN QUEENSLAND, AUSTRALIA Tamara L. Fletcher\ Steven W. Salisbury^'^ and Alex G. Cook^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia; ^Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA; ^Queensland Museum, PC Box 3300, South Brisbane, QLD 4101, AustraHa Key words: Pterosauria, Eromanga Basin, Cretaceous, Queensland Pterosaur fossils from Australia are rare. All the specimens that have been described thus far are Cretaceous in age, with the majority deriving from the Aptian-Albian succession within the Eromanga Basin of western Queensland. The Queensland specimens have tentatively been referred to the pterodactyloid families Pteranodontidae and Omithocheiridae. In light of their fragmentary nature, more specific referrals of these specimens have not been possible. As such, the overall composition and more precise relationships of Australia's Cretaceous pterosaur fauna have remained enigmatic. Over the last twenty years, five new pterosaur specimens have been found throughout the Eromanga Basin: a possible prepubis from the Late Aptian Doncaster Formation on Wrotham Park Station; a metacarpal IV from near Boulia and a wing phalanx from Dunluce Station (both from the Late Albian Toolebuc Formation); a partial mandible from a Toolebuc age equivalent formation east of Hughenden; and a possible humerus from the Late Albian Mackunda Formation at Vellum Downs, approximately 100km south-west of Hughenden. This new material is equally difficult to diagnose with certainty due to its fragmentary nature, but broad associations at family level can be made. The findings support connections to Omithocheiridae and Anhangueridae. The humerus may also indicate that more basal forms, such as archaeopterodactyloids, were also present in Queensland. The occurrence of anhanguerids - one of the most dominate pterosaur groups in broadly coeval South American faunal assemblages - and archaeopterodactyloids - also known from South America - suggest that Australia's Cretaceous pterosaurs formed part of a more widespread Gondwanan fauna. SAUROPODS FROM THE MID-CRETACEOUS (ALBIAN-CENOMANIAN) WINTON FORMATION OF CENTRAL-WESTERN QUEENSLAND, AUSTRALIA Steven W. Salisbury^ ^ Ralph E. Molnar^ and Matthew C. Lamanna^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia, s. sail sburv@uq .edu.au; ^Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA; ^Museum of Northern Arizona, 3101 N. Fort Valley Road, Flagstaff, AZ 86001, USA 26
Key words: Sauropoda, Winton Formation, Cretaceous, Queensland Sauropod body fossils are well known from the latest Albian-earliest Cenomanian Winton Formation of central-western Queensland. The material that has been described to date comprises several fragmentary skeletons, none of which has detailed collection data. Initially, this material was referred to Austrosaurus sp., based primarily on its close geographic proximity and similar age to the holotype of Austrosaurus mckillopi. While further preparation of the type material of A. mckillopi may reveal it to be diagnostic, features that have been used to refer the Winton material to Austrosaurus - such as camellate presacral vertebrae - are in fact found in all somphospondyl titanosauriforms. Although some of the Winton Austrosaurus material does display characteristics that would ally it with Titanosauria, it is too fragmentary to permit the establishment of a new taxon. Excavations at a new locality near the township of Winton between 2001 and 2004 have produced the associated remains of at least two titanosauriform sauropods. The bones of these animals were preserved in laterally discontinuous bands of fluvial siltstone, interpreted as the remnants of either oxbow lakes or crevasse splays from a series of flood events. This new material appears to belong to a single taxon that may share features with A. mckillopi, along with probable non-titanosaurian somphospondyls and basal titanosaurians from the mid-Cretaceous of Patagonia, such as Chubutisaurus insignis md Argentinosaurus huinculensis. The apparent close relationship with broadly contemporaneous Patagonian sauropods provides one of the first clear links between Australian and South American dinosaur faunas during the mid-Cretaceous.
NEW MATERIAL OF MEKOSUCHUSINEXPECTATUS (CROCODYLIA: MEKOSUCHINAE) FROM THE QUATERNARY OF NEW CALEDONIA Timothy R. Holt\ Steven W. Salisbury^ ^ Trevor H. Worthy^ Christophe Sand^ and Atholl Anderson^ ^School Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia (tim.holt,palaeo@gmail. com): ^Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213, USA; ^Department of Earth and Environmental Sciences, The University of Adelaide, SA 5005, Australia; "^Department of Archaeology and Natural History, Research School of Pacific and Asian Studies, Australian National University, Canberra, ACT 0200, Australia; ^Departement Archeologie, Service des Musees et du Patrimoine de Nouvelle-Caledonie, Noumea, New Caledonia Key words: Crocodylia, Mekosuchinae, Quaternary, New Caledonia New material of the small, pug-nosed eusuchian crocodyliform Mekosuchus inexpectatus is described from Quaternary deposits of the Pindai Caves, New Caledonia, South West Pacific. The new material permits the first detailed investigation of the cranial osteology of this crocodyliform, including a reconstruction of the skull. Comparisons confirm that Mekosuchus is monophyletic, with all species possessing a maxilla that participates in the orbit, a short, deep rostrum, a high alveolar process, palatal fenestrae extending rostrally to a point level with at least the seventh maxillary alveolus and a wide frontal between orbits. In light of the new material, Mekosuchus kalpokasi may need to be considered a junior synonym of M inexpectatus. The morphology of all Mekosuchus species suggests that their behaviour and ecology was comparable to that of extant species of Paleosuchus and the African dwarf crocodile, Osteolaemus tetrapsis.
NEW EOCENE CROCODILES FROM QUEENSLAND: IMPLICATIONS FOR MEKOSUCHINE EVOLUTION Lucas Buchanan School of Geosciences, Monash University, Clayton, VIC 3800, Australia, lucas.buchanan@sci.monash.edu.au Key words: Rundle Formation, Eocene, Kambara, Mekosuchinae 27
Fossil crocodile material recovered from freshwater, lacustrine sediments of the Rundle Formation (Eocene) in southeastern Queensland belongs to a new species of Kambara, a genus within the endemic Australasian clade, Mekosuchinae. This is the fourth species to be described within this genus, counting it among the earliest known mekosuchine remains and making Kambara one of the most taxonomically diverse of mekosuchine genera {Mekosuchus and Quinkana also contain four recognised species), illustrating that early Tertiary crocodilians may have been far more diverse than initially expected. This new deposit provides an unprecedented amount of material for this epoch with exquisite preservation. The new taxon possesses interlocking dentition, sub-parallel palatine structure similar to K. implexidens and distinct form of the retroarticular process from other described Kambara specimens, though it possesses a longitudinal ridge within the retroarticular fossa (also in K. molnari and Crocodylus species). Unique features include the mandibular symphysis reaching posteriorly to between the and alveoli, palatal fenestrae reaching anteriorly to the alveoli, a longitudinal ridge dividing the pterygoid fossa, and the possession of 14 maxillary alveoli. Furthermore, the expansion of the postroventral surface of the angular and the exaggeration of the medial portion of the articular form exaggerated attachment sites for the following jaw adductors and related structures: M. pterygoideus posterior, mandibular adductor tendon laminae (anterior inferior and posterior), and posterior pterygoid tendon lamina superior. Such features have potential to provide greater insight into both this genus and the overall relation of Mekosuchinae to Crocodylidae. SNAKE ORIGINS AND THE INTERACTION OF MORPHOLOGICAL AND MOLECULAR DATA SETS Michael S.Y. Lee School of Earth and Environmental Sciences, University of Adelaide, SA 5005 and Natural Sciences Building, South Australian Museum, Adelaide, SA 5000, Australia Key words: snake origins, molecular phylogeny, anguimorphs A combined analysis, including fossil and living taxa, morphology and nine nuclear genes, robustly resolves snakes as the sister taxon to anguimorph lizards (monitors, gila monsters, slow worms etc). This result is not generated by either morphology or molecules when analysed alone: morphology tends to nest snakes deep within anguimorphs, whereas the molecular data generates a trichotomy between three clades - iguanians, anguimorphs, and snakes. In the combined analysis, the molecular signal is sufficiently strong that morphology is prevented from nesting snakes within anguimorphs: it is largely constrained to choose between alternative resolutions of the iguanian-anguimorph-snake trichotomy generated by the molecular data. Faced with this restricted set of choices, the morphology strongly supports one of the three resolutions: snakes with anguimorphs. Thus, in the combined analyis, both data sets interact to strongly support a set of relationships that neither data set is capable of retrieving in isolation. There may be many such instances in which the morphological data converges on a spurious tree if analysed by itself, but if forced to choose between plausible trees (in a combined analysis) makes the "correct" choice, and thus generates valuable phylogenetic signal. FUNCTIONAL MORPHOLOGY OF A VARANID SKULL AS REVEALED BY FINITE ELEMENT ANALYSIS Karen Moreno\ Stephen Wroe\ Philip Clausen ^ Colin McHenry^, Domenic D'Amore"^ and Emily Rayfield' ^School of Biological, Earth and Environmental Sciences, University of Sydney, NSW 2052, Australia, dinohuella@yahoo.com; ^School of Engineering, University of Newcastle, NSW 2308, AustraUa; ^School of Environmental and Life Sciences, University of Newcastle, NSW 2308, Australia; '^Faculty of Arts and Science, Division of Life Science, New Brunswick, NJ, 08901, USA; ^Department of Earth Sciences, University of Bristol, Bristol BS8 IRJ, UK Key words: biomechanics, kinematics, FEA, 3D modelling 28
The Komodo dragon (Varanus komodoensis) is unique in a number of respects: it is the largest living lizard, the largest animal known to reproduce by parthenogenesis, and one of the only two varanids that feed on relatively large prey (Auffenberg 1981; Watts et al 2006). However, although its biology and ecology have received considerable attention, and despite potential to elucidate feeding behaviour in dinosaurs and other extinct reptiles, there have been no detailed investigations into its cranial mechanics. Cranial kinesis, feeding kinematics and jaw adductor anatomy in living and extinct reptiles have also been the focus of considerable research (Gomiak et al 1982; Herrel et al 2001; lordansky 1996), but how, or in many cases even whether movement between skull bones occurs is also not well understood (Smith 1982). Here, using newly developed high resolution 3-D computer-modelling and finite element (FE) techniques, we show that the Komodo dragon has a highly kinetic skull, with surprisingly weak masticatory muscles, optimised to resist tensional loads. These mechanical attributes are consistent with detailed observational data showing that the animal removes flesh using asymmetric movements of the mandible. Postcranial, particularly cervical musculature, plays a major role. Our findings expand understanding of extant reptilian feeding ecology and provide insight into the behaviour of carnivorous dinosaurs with which V. komodoensis shares many cranial and dental features. AUFFENBERG, W., 1981. The Komodo monitor. University Presses of Florida, Gainesville, 405pp. GORNIAK, G.C., ROSENBERG, H.I. & GANS, C., 1982. Mastication in the Tuatara, Sphenodon punctatus (Reptilia: Rhynchocephalia): structure and activity of the motor system. Journal of Morphology 171,321-353. HERREL, A., MEYERS, J. J., NISHIKAWA, K.C., & DE VREE, F., 2001. The evolution of feeding pattems in lizards: modulatory complexity and possible constraints. American Zoologist, 41, 1311-1320. lORDANSKY, N.N., 1996. The temporal hgaments and their bearing on cranial kinesis in lizards. Journal of Zoology 239, 167-175. SMITH, K.K., 1982. An electromyographic study of the function of the jaw adducting muscles in Varanus exanthematicus (Varanidae). Journal of Morphology 173, 137-158. WATTS, P.C., BULEY, K.R. SANDERSON, S. BOARDMAN, W. CIOFI, C. & GIBSON, R., 2006. Parthenogenesis in Komodo dragons. Nature 444, 1021.
PHYLOGENY OF MIOCENE WATERFOWL: REALITY RELIES ON OVERCOMING HOMOPLASY Trevor H. Worthy Darhng Building, DP 418, Department of Earth and Environmental Sciences, The University of Adelaide, SA 5005, Australia, trevor.worthy@adelaide.edu.au Key words: Miocene fossils, Anatidae, phylogeny, homoplasy Determining phylogenies of birds, and particularly of waterfowl, using morphological datasets has been fraught with homoplasy issues. These involve convergences particularly related to diving specializations at one end of a spectrum and large size and terrestrial habitat at the other. The relationships of fossil taxa can only be determined from skeletal characters so a realistic assessment of their phylogeny requires addressing potential homoplasy issues. Here we use a dataset of 133 characters (128 osteological, 5 integumental) and a total of 57 terminal taxa to determine the phylogeny of the New Zealand EarlyMiddle Miocene, 19-16 Ma, taxa Manuherikia lacustrina, Dunstanetta johnstoneorum, Miotadorna sanctibathansi and the similar-aged European taxon Mionetta blanchardi. We show that use of simple topological constraints during phylogenetic analyses can mitigate homoplasy issues. The constraint was based on robust relationships between key taxa determined using molecular data; other taxa were allowed to "float" to their optimal positions (determined by morphology) within this framework. We found evidence for a relatively basal clade or grade of 'oxyurines' that included the Miocene fossils Mionetta, Dendrochen, Manuherikia, Dunstanetta, and the modem Biziura, Thalassornis, Oxyura, Nomonyx, Stictonetta and Malacorhynchus. Miotadorna grouped with Tadorna species exclusive of T. radjah. The phylogenetic positions of these fossils indicate that the clade of Tadorna species exclusive of T. radjah, and oxyurines (sensu lato), each arose before the Early-Middle Miocene (19-16 Ma).
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COPROLITES SHED NEW LIGHT ON THE DIET OF LATE HOLOCENE MOA IN SOUTHERN NEW ZEALAND Wood, J.R. \ Rawlence, N.J. Cooper, A. ^ ^Department of Geology, University of Otago, New Zealand; ^Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, SA 5005, Nicolas.j.rawlence@adelaide.edu.au Key words: Moa, diet, coprolite, ancient DNA In a land devoid of large mammals, moa were the dominant terrestrial herbivores in the prehuman ecosystems of New Zealand, prior to their extermination by humans about 700 years B.P. Ten species of moa in six genera are currently recognised, exhibiting significant morphological variation in bill shape and size of temporal fossae, suggesting diet played an important role in niche partitioning. However, direct subfossil evidence of moa diet is rare, with only a handful of preserved gizzard content samples from just four moa species in museum collections. Recent excavations in dry rockshelter and cave sites in semi-arid regions of southern New Zealand have uncovered significant deposits of moa coprolites, providing an exciting new resource for studying moa diet and their impact on New Zealand's prehuman ecosystems. We report preliminary results from a study of these coprolites, utilising analyses of plant macrofossils (seeds, twigs, leaves) and ancient DNA to determine the species of moa that deposited the coprolite and its diet. Coprolites from the Dart River Valley in western Otago, were identified as being from the South Island giant moa {Dinornis robustus). The coprolites revealed that the diet of these birds consisted mainly of low, early successional plants including those with adaptations previously reported to have evolved in response to moa browsing (toxic, spiny, divaricating and prostrate plants). This represents significant intraspecific diet variation when contrasted with previous gizzard content for this species which consisted mostly of twigs and seeds from tall shrubs and trees. Megalapteryx didinus coprolites from Central Otago contained relatively abundant seeds of short spring annual herbs that are now rare or endangered, and restricted to areas most heavily browsed by sheep and rabbits. The dispersal and success of these plants may have been reliant on moa browsing and disturbance, for which introduced mammals are now surrogates.
A DROMORNITHID BIRD BARAWERTORNIS TEDFORDIYKOM THE MID-CENOZOIC OF RIVERSLEIGH, NORTHWESTERN QUEENSLAND Jacqueline Nguyen and Sue Hand School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia, j.nguyen@ unsw.edu.au Key words: dromomithid, Barawertornis, phylogenetics, Riversleigh Hind limb elements of the enigmatic dromomithid Barawertornis tedfordi are described from the Riversleigh World Heritage Area, northwestern Queensland. Phylogenetic analysis of this new material challenges previous conclusions that B. tedfordi is the plesiomorphic sister group to all other dromomithids. Its precise phylogenetic position, however, remains unresolved. However, apart from B. tedfordi, the phylogeny presented here is consistent with previous studies regarding the relationships among the other dromomithids, and supports a formal revision of dromomithid nomenclature. Barawertornis tedfordi is similar in size to the Southem Cassowary. Like the Southern Cassowary, it was a rainforest dweller that exhibited a similar locomotory mode. Taphonomic evidence from the Riversleigh fossil deposits suggests that B. tedfordi was probably preyed upon by crocodiles. MURRAY, P.P. & MEGERIAN, D., 1998. The skull of dromomithid birds: anatomical evidence for their relationship to Anseriformes. Records of the South Australian Museum 31, 51-97.
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MURRAY, P.F. & VICKERS-RJCH, P. 2004. Magnificent mihirungs: the colossal flightless birds of the Australian dreamtime. Indiana University Press, Bloomington, 410pp. RICH, P.V. 1979. The Dromomithidae, an extinct family of large ground birds endemic to Australia. Bulletin of the Bureau of Mineral Resources, Geology and Geophysics 184, 1-194.
MAQUARIE ISLAND HOLOCENE FOSSIL BIRD REMAINS A.J.D. Tennyson^ and R.P. Scofield^ ^Museum of New Zealand, Te Papa Tongarewa, P.O. Box 467, Wellington, New Zealand, alant(SUepapa. govt.nz; ^Canterbury Museum, Rolleston Avenue, Christchurch 8001, New Zealand Key words: Macquarie Island, Holocene, bird, fossils Subantarctic Macquarie Island, southwest of New Zealand, has been heavily modified through human activities and the introduction of cats, rats and weka {Gallirallus australis). The extinction of two endemic birds is known to have occurred in historic times: Macquarie Island rail {Gallirallus macquariensis) and Macquarie Island parakeet (Cyanoramphus novaezelandiae erythrotis). Numbers of many other species breeding on the island have been much reduced. A detailed paper analysing Holocene fossil penguin bones from sites at Finch Creek and Bauer Bay was produced by McEvey and Vestjens following field studies carried out by them in 1957 and 1962 and including material collected by Gwynn in 1949 (McEvey & Vestjens 1974). However, although they collected "a few bones of species other than penguins", they made no attempt to identify them. Van Tets made further bone collections on Macquarie in 1973 (now in CSIRO but unpublished). Meredith (1985) examined fossil sites on the island during a brief visit and analysed the 1957 and 1962 non-penguin fossil collections (now held in the Museum of Victoria). We have re-examined all the previous Holocene non-penguin fossil collections and one of us (RPS) made further collections in 1995-1997. The small number of seabird and land bird remains recovered (other than penguins) include those of the extinct rail, the extinct parakeet and an apparently unknown species of teal {Anas sp.). A great deal more systematic excavation and analysis of fossils is required to help illuminate the pre-human bird fauna of Macquarie - the identity of large albatrosses and the teal are a priority. McEVEY, A.R. & VESTJENS, W.J.M., 1974. Fossil penguin bones from Macquarie Island, Southern Ocean. Royal Society of Victoria Proceedings 86, 151-174. MEREDITH, C., 1985. A search for fossil seabirds on Macquarie Island. Australasian Seabird Group Newsletter 22, 9-13.
A NEW EOCENE ROLLER (AVES, CORACIODEA) FROM NORTH AMERICA: INSIGHTS INTO EARLY ROLLER MORPHOLOGICAL EVOLUTION AND BIOGEOGRAPHY. Daniel Ksepka, Julia Clarke, Adam Smith and Mark Noreil Department of Vertebrate Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA, dksepka@amnh.org Key words: Coracioidea, Aves, phylogeny, biogeography The Coracii are a group of colorful, large-headed birds that feed on small vertebrates and insects. These birds are referred to as rollers because of their acrobatic flight patterns. Extant rollers comprise a species depauparate group with an exclusively Old World distribution. Recently a fossil species from the early Eocene Green River Formation, of North America, Primobucco mcgrewi, was recognized as a basal member of the roller stem lineage, Coracioidea. Related Eocene stem species from Europe have indicated extensive morphological diversity and a distinct seed-eating diet as present in these early parts of the lineage. So far no Paleogene species has been placed within the extant roller radiation, or crown clade. Here, we report a complete skeleton of a new roller species from the Green River Formation. The new species is larger and possesses a strikingly different beak morphology from Primobucco mcgrewi, 31
expanding our understanding of New World roller diversity in the Paleogene. Preliminary phylogenetic analysis of the largest data matrix yet assembled for roller relationships places the new species as a stem member of the Coracioidea, but closer to the crown clade Coracii than Primobucco mcgrewi. The relative placements of these and other fossil rollers result in an ambiguous optimization of ancestral areas at the base of the clade, and raise the possibility of a North American origination for the Coracioidea.
NEW PTEROSAUR FOSSILS FROM THE EARLY CRETACEOUS (APTIAN-ALBIAN) OF WESTERN QUEENSLAND, AUSTRALIA Tamara L. Fletcher^ Steven W. Salisbury^'^ and Alex G. Cook^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia, Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA, ^Queensland Museum, PC Box 3300, South Brisbane, QLD 4101, Australia Key words: Pterosauria, Eromanga Basin, Cretaceous, Queensland Pterosaur fossils from Australia are rare. All the specimens that have been described thus far are Cretaceous in age, with the majority deriving from the Aptian-Albian succession within the Eromanga Basin of western Queensland. The Queensland specimens have tentatively been referred to the pterodactyloid families Pteranodontidae and Omithocheiridae. In light of their fragmentary nature, more specific referrals of these specimens have not been possible. As such, the overall composition and more precise relationships of Australia's Cretaceous pterosaur fauna have remained enigmatic. Over the last twenty years, five new pterosaur specimens have been found throughout the Eromanga Basin: a possible prepubis from the Late Aptian Doncaster Formation on Wrotham Park Station; a metacarpal IV from near Boulia and a wing phalanx from Dunluce Station (both from the Late Albian Toolebuc Formation); a partial mandible from a Toolebuc age equivalent formation east of Hughenden; and a possible humerus from the Late Albian Mackunda Formation at Vellum Downs, approximately 100km south-west of Hughenden. This new material is equally difficult to diagnose with certainty due to its fragmentary nature, but broad associations at family level can be made. The findings support connections to Omithocheiridae and Anhangueridae. The humerus may also indicate that more basal forms, such as archaeopterodactyloids, were also present in Queensland. The occurrence of anhanguerids - one of the most dominate pterosaur groups in broadly coeval South American faunal assemblages - and archaeopterodactyloids - also known from South America - suggest that Australia's Cretaceous pterosaurs formed part of a more widespread Gondwanan fauna.
DENTAL MORPHOLOGY OF SUDAMERICIDAE: GONDWANTHERIAN MAMMALS FROM THE CRETACEOUS AND PALEOGENE OF GONDWANA Yamila Gurovich^ and Gregory P. Wilson^ ^School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia, vamilag@gmaiLcom: ^Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Blvd., Denver, Colorado 80205-5798 USA Key words: Gondwanatheria, Mammalia, Dental Morphology Gondwanatherians are a Cretaceous and Paleogene radiation of Gondwanan mammals. They are currently known from Argentina, Madagascar, India, and Western Antarctica (Seymour Island), as well as a tentative dentulous dentary from the Cretaceous of Tanzania. No gondwanatherians have been discovered in Australia, New Zealand or Eastem Antarctica. They were originally classified as placental xenarthrans thep later based on dental similarities placed in the Order Multituberculata and more recently Mammalia incertae sedis. However the phylogenetic relationships of Gondwanatheria have yet to be resolved. The Gondwanatheria comprises small-crowned brachyodont multi-cusped forms (Femgliotheridae) and high-crowned more complex forms, with a characteristic flat worn occlusal surface (Sudamericidae). The 32
Sudamericidae includes Gondwanatherium (Cretaceous Argentina), Sudamerica (Paleocene Argentina), Lavanify (Cretaceous Madagascar), an Antarctic form (Eocene Seymour Island) and an Indian form which has recently been named (Wilson et al in press). The Sudamericidae dental morphology consists of high crowned molariforms, with a thick layer of enamel, sub-rounded to rectangular outline of the occlusal surface, occlusal furrows that extend vertically down the crown and reach the base of the crown (in Sudamerica, Lavanify and the Indian form). The Indian form and Lavanify both possess deep infundibula, perikymata, and derived enamel microstructure demonstrating stronger phylogenetic links between the two. The Antarctic sudamericid shares characters in the enamel microstructure of the lower incisor with Sudamerica, suggesting a close relationship between the two taxa. Gondwanatherium and Sudamerica also share occlusal morphology and large hypsodont crown size. Dental morphology of Sudamericidae is discussed and phylogenetic interpretations presented for Sudamericidae. WILSON, G.P., ANANTHARAMAN, S., DAS SARMA, D. & C. {in press) Late Cretaceous Sudamericid gondwanatherians from India. Journal of Vertebrate Paleontology. A MIOCENE TERRESTRIAL MAMMAL FROM NEW ZEALAND Trevor H. Worthy^ Suzanne J. Hand^ Michael Archer^ Robin M.D. Beck^ Alan J.D. Tennyson^ Anne M. Musser^ Craig Jones^ Barry J. Douglas^ and James A. McNamara^ * Darling Building, DP 418, Department of Earth and Environmental Sciences, The University of Adelaide, SA 5005, Austraha; e-mail: trevor. worthyi@adelaide.edu.au; ^School of Biological, Earth and Environmental Sciences, University of New South Wales, NSW 2052, Australia; ^Museum of New Zealand Te Papa Tongarewa, PO Box 467, Wellington, New Zealand; "^Australian Museum, 6-8 College Street, Sydney, NSW 2010, Australia; ^Institute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, New Zealand; ^Douglas Geological Consultants, 14 Jubilee Street, Dunedin, New Zealand; ^South Australian Museum, Adelaide, SA 5000, Australia Key words: Terrestrial mammal. New Zealand, Miocene A brief presentation will be made on fossils from rocks of the Manuherikia Group, Early-Middle Miocene (19-16 Ma), that reveal the presence of non-volant terrestrial mammals in the St Bathans Fauna from the Tertiary of New Zealand. Three bones, a proximal part femur, and two part mandibles, minimally indicate at least one mouse-sized mammal taxon. Osteological features of the femur indicate this taxon was more derived than basal mammals such as Morganucodontans but exclude it from membership of Trechnotheria. The mandibles are highly autapomorphic making interpretation of affinity difficult. We interpret this material as reflecting a ghost lineage of stem-therians that survived on Zealandia following disruption of Gondwana about 80 Ma. THE EARLY CRETACEOUS FLORA AND FAUNA OF LIGHTNING RIDGE, NEW SOUTH WALES FROM THE AUSTRALIAN MUSEUM COLLECTIONS Anne M. Musser and Robert K. Jones Australian Museum, 6 College St., Sydney, NSW 2000, Australia, anne.musser@austmus.gov.au Key words: Lightning Ridge; Early Cretaceous; Australian Museum; dinosaurs The Australian Museum Lightning Ridge fossil collection is a globally significant assemblage of Early Cretaceous plant and animal remains recovered from the opal fields of Lightning Ridge (north central New South Wales, Australia). Although the Lightning Ridge fossils are mostly fragmentary and not articulated, the site is unique in having abundant opalised plant and animal remains fossilised together, providing a clear snapshot of a complete Early Cretaceous Australian palaeocommunity. Fossils were discovered at Lightning Ridge early in the twentieth century as opal mining in the area became established, and the first fossils were brought to the Australian Museum in 1914. The first publication on Lightning Ridge fossils described the small crocodile 'Crocodylus' selaslophensis (Etheridge, 33
1917). Since the purchase of the Galman Collection in 1984, the collection has grown substantially. Palaeontologists Ralph Molnar, Tom Rich, Alex Ritchie and Robert Jones have taken an active interest over the past few decades, casting fossils on site and encouraging the donation of opalised fossils to the Australian Museum collection (particularly via the Cultural Gifts Program). Here we present a catalogue of the Lightning Ridge collection, a project incorporating identification, description, photography and illustration of key fossils in the collection. This diverse biota includes plants (mainly araucarian pine cones, petrified wood and twigs); invertebrates (yabbie buttons or gastroliths, a wide range of bivalve molluscs, and gastropods); lungfish; teleosts; turtles; plesiosaurs; a pliosaur propodial; pterosaurs; crocodiles (in addition to the holotype of 'Crocodylus' selaslophensis); several types of dinosaur (including the theropod Rapator ornitholestoides and the hypsilophodont Fulgurotherium australe); a possible therapsid (alternatively a mammal); birds; and mammals (including the monotreme Steropodon galmani, other monotremes, and the highly derived, bunodont mammal Kollikodon ritchiei). Dinosaur material includes isolated omithopod, sauropod and theropod teeth (the omithopod tooth possibly referable to Muttaburrasaurus), hypsilophodontid postcranials, vertebrae, various toe bones and other postcranials. DO CENOGRAMS WORK ON MARSUPIAL FAUNAS? COMPARISON WITH OTHER PALAEOECOLOGICAL TECHNIQUES AND IMPLICATION FOR THE RIVERSLEIGH FAUNAS Kenny J. Travouillon^'Serge Legendre^, Michael Archer^ and Suzanne J. Hand^ ^School of Biological, Earth and Environmental Sciences, University of New South Wales, NSW 2052, Australia;'UMR 5125 PEPS, CNRS, France; Universite Lyon 1, Campus de La Doua, Bt. Geode, 69622 Villeurbanne cedex, France kennytravouillon@hotmail.com Key words: Cenograms, Body size distributions, Palaeoecology, Riversleigh The cenogram method, developed by Legendre (1986, 1989) and based on Valverde's (1964, 1967) original method, has yet to be used on marsupial faunas. A cenogram is a graphical representation of the body weight distribution of species within a community. Legendre (1986, 1989) demonstrated that the shape of cenograms could be used to interpret palaeoenvironement conditions. In the present study, we test the cenogram method using modem species lists of mammals from 53 national parks all over Australia. Globally, open environments have been shown to lack mammals between 500 g and 8 kg (Legendre, 1986; 1989). Modem Australian open environments show a similar absence of mammals of body masses between lOOg and 1 kg. Regressions were used to find a correlation between body size distribution and environmental factors (rainfall, vegetation type, temperatures...). Rainfall and vegetation type were found to strongly correlate (R^ over 70%) with body mass distribution. Similar regressions were performed using mammal locomotion and diet data to compare with the body size distribution regression. Body sizes for fossil taxa from Riversleigh were calculated using regressions of body size on dental measurements for modem marsupials by Myers (2001). The cenograms of the Riversleigh faunas were built to interpret the palaeoenvironment changes through time, from a closed and humid (Late Oligocene) to an open and arid (Late Miocene) environment. LEGENDRE, S., 1986. Analysis of mammalian communities from the late Eocene and Oligocene of southem France. Palaeovertebrata 16, 191-212. LEGENDRE, S., 1989. Les communautes de mammiferes du Paleogene (Eoctee superieur et Oligocene) d'Europe occidentale: stmctures, milieux et eolution [in French with English abstract]. Miinchner Geowissenschaft' liche Abhandlungen, Reihe A, Geologic undPaldontologie 16, 1-110. MYERS, T.J., 2001. Prediction of marsupial body mass. Australian Journal of Zoology 49, 99-118. VALVERDE, J.A., 1964. Remarques sur la stmcture et revolution des com-munautes de vertebres terrestres. 1. Stmcture d'une communaute 2. Rapport entre predateurs et proies.La Terre et la Vie 111, 121-154. VALVERDE, J. A., 1967. Estmctura de una communidad de vertebrados terrestres. Monografias de la Estacidn Biologica deDohana 1, 1-129. 34
A BASIS FOR THE DEFINITION OF AUSTRALIAN NEOCENE 'MARSUPIAL AGES% AND A RATIONALE FOR DOING SO Dirk Megirian\ Gavin Prideaux^, Peter Murray^ and Neil Smit^ ^Museums and Art Galleries of the Northern Territory, Museum of Central Australia, PO Box 3521, Alice Springs, NT 0871, Australia, dirk jiiegirian@nt.gov.au. ^Flinders University of South Australia, GPO Box 2100, Adelaide, SA 5001, Australia. ^ Marine Biodiversity Group, Department of Natural Resources, Environment and the Arts, PO Box 41775, Casuarina, NT 0811, Australia Key words: Chronostratigraphy, stage of evolution biochronology, Land Mammal Ages, Australian 'marsupial ages' Chronostratigraphy and stage of evolution (SOE) biochronology are the basis of the formalised Land Mammal Ages (LMAs) of other continents. Step-wise seriation of a taxon-locality matrix of species-level occurrence data for Australian Neogene marsupials, to which constraints of chronostratigraphic succession and the irreversibility of organic evolution are applied, quite neatly differentiates a succession of biochrons. A succession of Land Mammal Ages should ideally contain no temporal gaps, with boundaries between LMAs defined by chronostratigraphic markers ('datum events'). Marsupial data for Australia are, however, insufficient to resolve any biological 'datum events', and the Neogene record is clearly patchy, but the biochrons resolved by the constrained seriation method do satisfy Lindsay's (2003) definition of a land mammal age as: "...a relatively short interval of geological time that can be recognised and distinguished from earlier and later such units (in a given region or province) by a characterising assemblage of mammals". Named 'marsupial ages' would provide a tool for expressing Australian faunal succession in terms of its own distinctive nature, to be amended as new data become available. This is preferable to continuing with the practice of trying to express it in terms of the chronometrically wellcalibrated International Chronostratigraphic Scale (Gradstein et al 2004), when most of our fossil occurrences are undated, or only poorly dated. GRADSTEIN, P.M., OGG, J.G., & SMITH, A.G. eds, 2004. A Geological Timescale 2004, Cambridge University Press, 589pp. LINDSAY, E., 2003. Chronostratigraphy, Biochronology, Datum Events, Land Mammal Ages, Stage of Evolution, and Appearance Event Ordination. Bulletin of the American Museum of Natural History 279, 212-230
PETROSALS AND TARSALS OF THE EARLY EOCENE MARSUPIAL DJARTHIA MURGONENSIS: IMPLICATIONS FOR THE EVOLUTION AND BIOGEOGRAPHY OF AUSTRALIDELPHIA Robin M.D. Beck, Henk Godthelp, Michael Archer and Suzanne J. Hand School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia, robin,beck@.studcnt.unsw,edu.ai-i: Key words: Australidelphia, Djarthia, petrosals, tarsals, The early Eocene Tingamarra fauna near Murgon, Queensland, contains the oldest known Australasian marsupials. So far, only the teeth of several Tingamarran marsupials have been described. Here we discuss non-dental marsupial specimens - isolated petrosals and tarsals - that we tentatively refer to the 'marsupicamivore' Djarthia murgonensis Godthelp et al 1999, based on relative size and abundance. Collectively, the character states exhibited by this new material and the previously described dentition of Djarthia (Godthelp et al, 1999) suggest that it is the most plesiomorphic known member of Australidelphia (the clade that includes all extant Australasian marsupials and the South American microbiotheres). This conclusion is supported by phylogenetic analysis based on the large morphological dataset of Horovitz and Sanchez-Villagra (2003), as well as total evidence and molecular scaffold analyses using the molecular supermatrix of Beck (in review), and is congruent with Godthelp et al's (1999) suggestion that Djarthia resembles a 'prototypical' Australian marsupial. The presence of at least one undoubted australidelphian in the early Eocene of Australia contrasts with the equivocal evidence for 35
members of this clade in similarly-aged deposits in South America; notably, no tarsals with the diagnostic australidelphian 'continuous lower ankle joint' are known from either the Middle Palaeocene (59.2-60.4 MYA) Tiupampa fauna of Bolivia or the Late Palaeocene (58.7-69.2 MY A) Itaborai fauna of Brazil. We discuss the implications these findings have for marsupial biogeography, in the context of molecular divergence dates estimated by Beck (in review). BECK, R.M.D, in review. A dated phylogeny of marsupials using a molecular supermatrix and multiple fossil constraints: comparison with the fossil record. Journal of Mammalogy. GODTHELP, H., WROE, S. & ARCHER, M., 1999. A new marsupial from the early Eocene Tingamarra Local Fauna of Murgon, Southeastern Queensland: a prototypical Australian marsupial? Journal of Mammalian Evolution 6, 289-313. HOROVITZ, L & SANCHEZ-VILLAGRA, M.R., 2003. A morphological analysis of marsupial mammal higher-level phylogenetic relationships. Cladistics 19, 181-212.
EARLY PSEUDOCHEIRID EVOLUTION REVEALED BY THE OLIGO-MIOCENE LOCALITIES OF RIVERSLEIGH AND CENTRAL AUSTRALIA. Karen Roberts and Mike Archer School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, AustraHa,.k.roberts@student.unsw.edu.au Key words: Pseudocheiridae, Riversleigh, Oligo-Miocene, ringtail possums A large proportion of what is presently understood about the earhest ringtail possums (Pseudocheiridae: Marsupialia) is based on dental fossil material from the Oligo-Miocene deposits of the Lake Eyre Basin and Tirari Desert in central AustraHa. However, the Oligo-Miocene localities of Riversleigh, northwestern Queensland, are known to have produced a large collection of craniodental pseudocheirid material. In association with known groups, the Riversleigh collection has provided a wealth of information regarding the species-level understanding of this family. In addition to the pubhshed genera, Pildra, Paljara, Marlu and Gawinga, at least one new genus is recognised from Riversleigh as well as representatives of the extant genus complex of Pseudochirops, Currently twelve new species have been identified from Riversleigh as well as the Leaf Locality and Tedford Quarry in central Australia, and help piece together the relationships and diversity patterns of this family.
FUNCTIONAL PEDAL MORPHOLOGY OF PLEISTOCENE KANGAROOS FROM THE NULLARBOR PLAIN Natalie M. Warburton^'^ and Gavin J. Prideaux^'^ ^ Western Australian Museum, Locked Bag 49, Welshpool DC, WA 6986, Australia, nwarbo@graduate.uwa.edu.au; ^ The University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia; ^ Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia Key words: Macropodidae, tarsal bones, tree-kangaroos, ecomorphology Extant macropodids (kangaroos, wallabies and rat-kangaroos) are unique among large mammals in their adaptation to a bipedal bounding, or saltatorial, mode of locomotion. As a consequence, the form of the pes is unique, and typified by disproportionate enlargement of the fourth and fifth digits, and an ankle joint modified for structural strength rather than rotational flexibility. Still, extant macropodids do vary in pedal form and function in relation to habitat preferences and ecologies, with open plains specialists at one extreme and tree-kangaroos at the other. Ecomorphological studies of extinct macropodid assemblages hold promise for expanding our understanding of community palaeoecology and environmental traits, but few such studies have yet been made. Here we discuss preliminary morphological and morphometric analyses of the feet of kangaroo species in the middle Pleistocene Thylacoleo Caves assemblages from the Nullarbor Plain. We find that pedal morphologies of species of the extinct genera Baringa, Bohra, Protemnodon and Congruus are equally as distinctive as species of the better-known genera Macropus, 36
Procoptodon, Sthenurus and Bettongia, providing insights into their own speciaHsed locomotory aptitudes.
DYNASTIES: TOWARDS AN UNDERSTANDING OF THE TAXONOMY AND PALAEOBIOLOGY OF THE LARGEST-EVER MARSUPIAL (DIPROTODONTOIDEA, MARSUPIALIA) Gilbert J. Price School of Natural Resource Science, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia; Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis, University of Queensland, St. Lucia, QLD 4072, Australia, ^.price l@uq.edu.au Kew words: Diprotodontoidea, taxonomy, paleobiology Significant numbers of studies have addressed aspects relating to the processes, timing, and geography of late Pleistocene megafaunal extinctions. However, it is fundamentally important to be able to constrain the rate of late Pleistocene faunal losses, an aspect reliant on having accurate taxonomic information for the extinct species. Adequate accurate taxonomic information is lacking for several groups, in particular, for the Australian Owen 1838. Essentially, Diprotodon filled the role of the Pleistocene 'big game' megaherbivore of Australia. Diprotodon taxonomy has been complicated by early nomenclatural problems and by the occurrence of two distinct size-classes of individuals that do not reflect an ontogenetic series. Traditionally, the two size-classes have been regarded as separate species. However, a taxonomic investigation of large samples (>1000 teeth) of Diprotodon material from several different fossil localities including the Darling Downs (Queensland), Glen Innes and Bingara (New South Wales), Lake Callabonna (South Austraha), and Lancefield and Bacchus Marsh (Victoria), suggests that there is little evidence for the discrimination of more than one morphospecies. Thus, Diprotodon is here considered a monotypic genus and the single morphospecies, D. optatum Owen 1838, is considered to have been highly sexually dimorphic. By drawing analogy to extant sexually dimorphic megaherbivores and marsupials, the large-form was probably male, and the small-form was probably female. D. optatum probably moved in small, gender-segregated herds, and exhibited a polygynous breeding strategy. As a single morphospecies, D. optatum had a near-continental geographic distribution, similar to that of extant megaherbivores, possibly indicating its niche as a habitat generalist.
DIPROTODONTID FOOTPRINTS FROM THE PLIOCENE OF CENTRAL AUSTRALIA Aaron Camens Darling Building, DP 418, Department of Earth and Environmental Sciences, University of Adelaide, SA 5005, Austraha, email: aaronxamens-@adelaide.edu.au Key words: trackways, Diprotodontoidea, Tirari Formation Several diprotodontid (Diprotodontoidea, Marsupialia) trackways preserved in the sediments of the middle Pliocene Tirari Formation, Warburton River, northern South Australia, provide evidence of the locomotory methods and gait of this family. The footprints are tentatively attributed to Euowenia grata (De Vis), the only diprotodontid known from fossil material in the main body Tirari Formation. Average stride length was 98.2 cm while average track width was 27.1 cm suggesting a species much smaller than Diprotodon optatum, the only other diprotodontid for which fossil trackways have been found. A footprint collected from the site revealed the structure of the fleshed hind-foot complete with some pad impressions and demonstrates the group's affinities with vombatids. It is thought that the mode of footprint preservation, where each print is pedestalled above the surrounding sediment, is a result of the in-filling of prints by wind-blown sediment, which is then cemented and the softer sediment surrounding the prints is eroded. This mode of trackway preservation appears to be unique to central Australia. The trackways were probably formed as diprotodontids made their way across a soft clay-pan and represent only the third fossil mammal trackways known from the Pliocene and Pleistocene of Australia. Calculations suggest that
37
the diprotodontid was moving across the clay-pan at an approximate speed of 3.5 km/h compared to 6.3 km/h for Diprotodon at Lake Callabonna. PALAEOBIOLOGICAL SIGNIFICANCE OF CHEEKTOOTH WEAR AND ATTRITION IN WAKALEO
K4AD£^/?L£^R£^/?/(THYLACOLEONIDAE)
Peter Murray and Dirk Megirian Museums and Art Galleries of the Northem Territory, Museum of Central Australia, PC Box 3521, Alice Springs, NT 0871, Australia, peter.murray@nt.gov.au Key words: Wakaleo vanderleueri, cheektooth wear, attrition, paleobiology Palaeobiological implications of functional morphology, wear, and attrition of the cheekteeth of Wakaleo vanderleueri (Thylacoleonidae) are examined in relation to Lars Werdelin's (1987, 1988) constraint hypothesis. Typical progression of cheektooth wear and attrition was reconstructed from a series of Miocene Bullock Creek LF Wakaleo specimens ordered in relative biological age by their states of continuous eruption. Wakaleo cheekteeth wear progresses from front to back simultaneous with continuous eruption, axial rotation of the lowers and mesial drift. Unworn Wakaleo molars have relatively large, basined talonids with not inconsiderable crushing/grinding area; but with progressive wear, the prehypocristid and its flanking surface are converted to an oblique shearing blade in the same plane as the elevated buccal shearing facet of the trigonid (paraconid-protoconid), which also functions initially as a thegotic guide. Attrition eventually traverses the entire crown to produce a flat, labially inclined surface with a trenchant lingual margin. As the attrition facets traverse the molar crowns, concomitant change in the occlusal angle is compensated by buccal rotation of the lower cheektooth row and continuous growth of the premolar and molar roots. Wakaleo vanderleueri and W. alcootaensis cheek teeth are often heavily worn, with enamel spalling and deep, striated attrition grooves. The ontogenetic changes in the cheek teeth of Wakaleo species are especially striking. Up to the point of pulp cavity exposure and spalling of progressively thinning internal margins, the apparent shearing potential of the molar row increases with wear. WERDERLIN, L., 1987. Jaw geometry and molar morphology in marsupial carnivores: analysis of a constraint and its macroevolutionary consequences. Palaeobiology 13, 342-350. WERDERLIN, L., 1988. Circumventing a constraint: the case of Thylacoleo camifex (Marsupialia: Thylacoleonidae). Australian Journal of Zoology 36, 565-571. TWO NEW FOSSIL DASYUROMORPHIAN GENERA AND THEIR SIGNIFICANCE Jonathan Cramb School of Natural Resource Sciences, Queensland University of Technology GPO Box 2434, Brisbane, QLD 4001, Australia, j2.cramb@student.qut.edu.au Key words: Dasyuromorphian, Mt Etna Recent study of dasyurid assemblages from cave sites in eastern central Queensland has revealed unexpectedly high diversity and several new species, including two new genera (here designated as A and B). Gen. nov. A is a medium {Phascogale-^izQd) species found in deposits with two other similarly sized dasyurids, suggesting a community structure not seen in extant Australian rainforests. Gen. nov. B is a tiny (Planigale-sizQd) probable dasyurid known only from its unusual upper dentition. This seems to indicate a specialised diet, a rarity among extant dasyurids. These two genera suggest that the midPleistocene rainforests of eastern central Queensland were unlike any extant Australian rainforest communities.
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CONVERGENCE AND REMARKABLY CONSISTENT CONSTRAINT IN THE EVOLUTION OF CARNIVORE SKULL SHAPE Stephen Wroe^ and Nicholas Milne^ ^School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, Australia, 2052, SAvroe@unsw.edu.au: ^School of Anatomy and Human Biology, The University of Western Australia, Nedlands, WA 6009, Australia Key words: convergence, Marsupialia, Camivora Phenotypic similarities between distantly related marsupials and placentals are commonly presented as examples of convergence and support for the role of adaptive evolution in shaping morphological and ecological diversity. Here we compare skull shape in a wide range of camivoran placentals (Camivora) and non-herbivorous marsupials using a 3-D geometric morphometric approach. Morphological and ecological diversity among extant camivorans is considerably greater than is evident in the marsupial order Dasyuromorphia with which they have most commonly been compared. To examine convergence across a wider, but broadly comparable range of feeding ecologies, a dataset inclusive of nondasyuromorphian marsupials and extinct taxa representing morphotypes no longer present was assembled. We found support for the adaptive paradigm, with correlations between morphology, feeding behavior and bite force, although skull shape better predicted feeding ecology in the phylogenetically diverse marsupial sample than in camivorans. However, we also show that remarkably consistent but differing constraints have influenced the evolution of cranial shape in both groups. These differences between camivorans and marsupials, which correlate with brain size and bite force, are maintained across the full gamut of morphologies and feeding categories, from small insectivores and omnivores to large meat-specialists.
CONSTRUCTING A SPATIALLY-CONSTRAINED CHRONOLOGY OF MEGAFAUNA EVOLUTION AND EXTINCTION IN EASTERN AUSTRALIA Gilbert J. Price\ Jian-xin Zhao\Yue-xing Feng^ and Scott A. Hocknull^ ^Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis, University of Queensland, St. Lucia, QLD 4072, Austraha. Email: g.pricel@uq.edu.au: ^Geosciences, Queensland Museum, 122 Gerler Road, Hendra, QLD 4011, Australia Key words: Megafauna, extinction, Pleistocene, dating Debate over the extinction of Australia's late Pleistocene megafauna (i.e., large-sized terrestrial animals) has become polarised in recent years, with the cause(s) traditionally pinned on either natural climate changes or anthropogenic influences (e.g., over-hunting). Failure to resolve the megafauna extinction debate is underpinned by a lack of the most basic data necessary to test leading hypotheses, i.e., accurate dating of megafaunal occurrences. Here, we present several new U/Th dates (including dating of flowstones, straw stalactites, calcite veins, calcite coatings/fillings on/in fossil remains) for a series of previously undated, classic megafauna-bearing localities from southeastern Queensland. The resuhs indicate that The Joint (Texas Caves) is middle Pleistocene in age or older (but younger than Pliocene); the adjacent Russenden Cave Bone Chamber (Texas Caves) is late Pleistocene and may date to around the time of the last megafauna in eastern Australia; and Cement Mills (Gore) appears to be late Pleistocene or older. The resuhs have significant implications for understanding megafauna evolution through time and the causes of their eventual extinction. This pilot study shows that combined U/Th dating of fossil teeth and speleothem materials associated with fossil assemblages has a great potential to resolve the long-term debate of megafauna extinction in Australia. Additionally, future dating and C-0 isotope analyses of stalagmites collected from the cave localities will be investigated for their potential to provide highresolution climatic data for the Quaternary of eastern Australia.
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WALLABIES & WOMBATS: NEW ZOOARCHAEOLOGICAL INTERPRETATIONS OF THE LATE PLEISTOCENE OCCUPATION OF SOUTHWEST TASMANIA. Jillian Garvey\ Richard Cosgrove^ and Anne Pike-Tay^ ^Archaeology Program, La Trobe University, Melboume,VIC 3086, Australia. i,garv^ey@latrobe>edu.au: ^Department of Anthropology, Vassar College, Poughkeepsie, NY 12604, USA Key words: Late Pleistocene, Kutikina Cave, skeletochronological analysis, zooarchaeology Vertebrate remains, dominated by Bennett's wallaby {Macropus rufogriseus) and to a minor degree the Common wombat {Vombatus ursinus), constitute the largest component of the archaeological assemblage in late Pleistocene Southwest Tasmania. This paper presents new zooarchaeological interpretations from Kutikina Cave (19,770-14,840 BP, formally Fraser Cave), Franklin River, excavated in 1981 (Kieman et al. 1983). Taphonomic analyses of the skeletal material (more than 269,000 bone fragments) identified 21 vertebrate species, 13 of which are considered potential human prey taxa. Of the potential human prey species more than 92% of the assemblage consisted of Bennett's wallaby. The distribution of body parts and elements indicates humans more frequently selected the hindlimbs and pes elements, with these bones frequently split to extract bone marrow. These results indicate that humans used complex economic strategies during the Last Glacial Maximum. To further explore this idea, we apply skeletochronological analysis to Bennett's wallaby from Tasmania's earliest archaeological sites, presenting results of seasonal teeth annuli growth which provide important age-at and season-at-death information. Results suggest that hunting occurred in upland and lowland valleys on a coordinated seasonal basis using what would be considered a relatively archaic Middle Palaeolithic stone technology. This is the first time that skeletochronology has been used in Australian zooarchaeology and provides important information into human subsistence and land use patterns. KIERNAN, K., JONES, R. & RANSON, D., 1983. New evidence from Fraser Cave for glacial age man in south-west Tasmania. Nature 301, 28-32.
EVIDENCE OF HUMANS AND MEGAFAUNA AT LAKE MENINDEE, NEW SOUTH WALES Jacqui Duncan Archaeology Program, La Trobe University,Melbourne, VIC 3086, Australia, j.duncan@latrobe.edu.au Key words: Extinction, Megafauna, Climate change. Overkill The Sunset Strip fossil-bearing locality at Lake Menindee preserves a diverse assemblage of marsupials, including several species of extinct megafauna. Many of the fossils found at the site are articulated or semi-articulated and include almost complete skeletons, indicating that aeolian sediments rapidly buried the animals following death. Recently obtained optical ages show the site and the fossils it contains date to the early part of the last glacial, from around 55,000 years ago. Intruding into the fossil bearing deposit was excavated a hearth dating to 45,100 ± 1400 yr ago, which is the oldest evidence of human occupation of the Darling River. No artefacts were identified in situ within the fossil-bearing unit, suggesting that the megafauna went extinct locally before the arrival of humans to the area. The fossils characterise a mass death assemblage indicating a catastrophic event or events brought about by local ecosystem stress due to climatic aridity, and not the result of human predation or anthropogenic causes.
PALAEOECOLOGY OF LATE QUATERNARY BAT FAUNA FROM MT ETNA, EASTERNCENTRAL QUEENSLAND, AND ITS RESPONSE TO ENVIRONMENTAL CHANGE: A PROJECT UNDERWAY Sandrine Martinez Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia, smartiii ez@ s tudent. gut. ediL aii 40
Key words: Quaternary climate change, bat communities, Australia The Quaternary was marked by highly fluctuating climate alternating between glacial and interglacial periods, and engendering floral and faunal extinctions that have altered the composition of many ecological communities. In Australia, glacial-interglacial fluctuations have been overprinted by increasing aridity through the late Pleistocene, leading to major retraction of rainforest habitat in, for instance, Queensland. While numerous studies have been conducted on the changes in the community structure of Quaternary mammals around the world, bats commonly have been excluded from palaeoecological analyses. Therefore, bat responses to climate change are very poorly known, especially in Australia. Recently, however, new fossil deposits located in central eastern Queensland at Mount Etna, near Rockhampton, have been discovered within a series of cave-fills exposed in cross-section by mining operations (Hocknull 2005). These fossil deposits contain a succession of vertebrate fossil assemblages ranging from >500 ka to the present and span the transition from full tropical rainforest habitats to the more arid environment that is currently present in the Mt Etna region (Hocknull et al, submitted). The present project will document the community structure and feeding guilds of multi-species bat faunas through this interval of climate change and link the information obtained from fossil data to the bat communities that still occur in Mt Etna caves today. Preliminary results show that late Pleistocene bat diversity at Mt Etna was higher than at present, and included hipposiderids, species whose distribution is today restricted to north Queensland. HOCKNULL, S.A., 2005. Ecological succession during the late Cainozoic of central eastern Queensland: extinction of a diverse rainforest community. Memoirs of the Queensland Museum 51, 39-122. HOCKNULL, S.A., ZHAO, J., FENG, Y. & WEBB, G.E., (Submitted). Mid-Pleistocene rainforest fauna extinction in eastern Australia. Geology. THE EVOLUTION AND GENETIC DIVERSITY OF THE EXTINCT TREMARCTINE BEARS Sarah Bray, Jeremy Austin, Ian Barnes, Jacobo Weinstock, Beth Shapiro and Alan Cooper Australian Centre for Ancient DNA, University of Adelaide, Adelaide, SA 5005, Australia, sarah .bray @adelai de. edu.au Key words: Ancient DNA, Tremarctine, bears The Tremarctine bears are a New World subfamily with origins in the Pliocene and contain five known genera {Plionarctos, Arctodus, Arctotherium, Pararctotherium and Tremarctos), of which four are now extinct. The only surviving member of the Tremarctine lineage is the South American Tremarctos ornatus (spectacled bear). The fossil record suggests that the North American Qy^imci Arctodus simus (giant shortfaced bear) and its South American relatives Arctotherium sp. and Pararctotherium sp., inhabited the New World until as recently as 21,000 - 10,000 years ago, but the evolutionary relationships of these taxa remains unclear. We have used ancient DNA techniques to retrieve mitochondrial DNA sequences from specimens of extinct Tremarctine bears across their range, with 17 samples from South America, Central North America, Canada and Alaska. Preliminary results indicate a large genetic divergence between the extinct North American and South American genera. Radiocarbon and isotopic analyses are currently underway to provide a temporal aspect and to analyse dietary differences in Tremarctine bears across the New World. Previous studies using stable isotope analysis have indicated that Arctodus simus was highly carnivorous in comparison to contemporaneous brown bears {Ursus arctos) who were omnivorous.
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COMPUTER SUPER-MODELLING OF HOMINID FACIAL FORM, FUNCTION AND FEEDING: WHY THE HEAVY BROW? Stephen Wroe\ Karen Moreno^ Philip Clausen^, Colin McHenry^ and Darren Curnoe^ ^School of Biological Earth and Environmental Sciences, University of New South Wales, NSW 2052, Australia; ^ s.wroe@unsw.edu.au; School of Engineering, University of Newcastle, NSW 2308, Australia; ^School of Environmental and Life Sciences (Geology), University of Newcastle, NSW 2308, AustraHa; "^School of Medical Sciences, University of New South Wales, NSW 2052, AustraHa Key words: biomechanics, hominid feeding ecology Finite Element (FE) analysis is a powerful engineering tool long used to predict the performance of manmade devices. Its application to biological structures is a recent development. A common focus of FE modelling in hfe sciences has been the investigation of relationships between skull structure and feeding behaviour. Although of considerable utility, the creation of such models has been time consuming and their resolution insufficient to incorporate the composite nature of bone. Here we present the most realistic FE models yet produced for a vertebrate skull, constructed using a largely automated method. They comprise two to three million brick heterogeneous simulations of the cranium, mandible and jaw closing musculature of a common chimpanzee. We apply these models to examination of a long-standing question in the field of primate biomechanics, i.e., has hypertrophy of the brow-ridge evolved as a means of distributing strain imposed during feeding? Our results do not support this proposal. Application of these techniques to fossil hominid material will be discussed. Findings further suggest that the complex, heterogeneous nature of bone in the skull acts to dissipate stress, but that consequently higher strain must be offset by additional energy. We hypothesise that despite obvious costs, this system may lend adaptive advantage through enhancing the organism's ability to modify its behaviour prior to the bone's reaching catastrophic failure.
Marine Mammals in Deep Time: Diversity, Distribution and Evolution THE EVOLUTION OF AQUATIC TETRAPODS IN THE SOUTHWEST PACIFIC R. Ewan Fordyce Department of Geology, University of Otago, Dunedin, NZ 9054. cwan.fbrdvce@stoncbow.otago.ac,nz Key words: Tetrapoda, extinction, paleoclimate, paleoclimate New Zealand and Australian strata produce significant fossils of secondarily aquatic tetrapods. Later Cretaceous and Cenozoic marine records are of interest because of major processes that affected reptiles, birds and mammals: the KT boundary event, changing geography - of land and ocean gateways - related to the final breakup of Gondwana, and the shift from greenhouse to icehouse earth. Australia offers earlier Cretaceous assemblages. New Zealand late to latest Cretaceous: ichthyosaurs, plesiosaurs, mosasaurs, sea turtles, and rare birds. New Zealand, with continuous marine sedimentation through the KT boundary, has promise to link aquatic tetrapods to boundary events. For the Cenozoic, the Paleocene and earlier Eocene records are sparse for New Zealand and Australia, but Oligocene and younger fossils are more common. Notable aspects of Cenozoic aquatic tetrapods are: Paleocene stem penguins (archaic wing-propelled diver Waimanu), indicating a Cretaceous crown-bird radiation; Eo-Oligocene diversification of penguins including "giant" species; invasion of southern waters by archaic whales by Late Eocene; explosive radiation of whales and dolphins in the Oligocene, related to climate/circulation changes; first appearance of pinnipeds in the later Miocene; radiation of modem (crown) families of cetaceans, and modem (crown) genera of penguins from the Late Miocene onwards. There are sporadic records of non-penguin birds, and of chelonians. Longterm pattems of evolution and extinction have been attributed to both biological (e.g. competition) and physical (e.g. climate change) drivers. Next, we must: expand the meagre Australian record, better use well-dated NZ fossils to calibrate molecular clocks, and do more alpha taxonomy. 42
AN EVOLUTIONARY HISTORY OF MARINE MAMMALS IN AND AROUND AUSTRALIA Erich M. G. Fitzgerald School of Geosciences, Monash University, VIC 3800, Australia; Museum Victoria, GPO Box 666, Melbourne, VIC 3001, Australia, efitzger@museum.vic.gov.au Key words: marine mammals, evolution, fossil record, Australia Fossil marine mammals (primarily cetaceans) have been recovered from southeast Australia in strata ranging in age from Early Oligocene through Holocene, providing a preliminary outline of marine mammal evolution in this region. Cetaceans were present in Australian waters by the Early Oligocene. Late Oligocene assemblages consist of late-surviving archaeocetes, and stem group mysticetes and odontocetes. No crown clades of Neoceti are yet known from pre-Miocene sediments. The Early-Middle Miocene fauna is broadly similar to that known from the fringes of the Southern, North Pacific and Atlantic oceans, and includes the earliest occurrence of an extant family (Physeteridae). Late Miocene assemblages include the earliest Australian records of Balaenidae, Balaenopteridae, Delphinidae and Phocoenidae. Latest Miocene to Early Pliocene assemblages include the earliest records of Sirenia, pinnipeds (Phocidae) and extant cetacean genera, as well as archaic taxa (Cetotheriidae, extinct physeterids, possible kentriodontids), and extant clades now absent from Australian waters (e.g. Phocoenidae). The mid-Late Pliocene fauna is essentially modem in composition (including extant delphinid genera), with notable exceptions being the occurrence of phocid pinnipeds and sirenians in Victoria. Neo-species are first recorded in the Pleistocene, as is the pinniped family Otariidae. Holocene marine mammal diversity and distribution patterns are similar to the Recent, although dugongs are known from Victorian deposits. The broad pattern outlined here indicates that the 'modem' Australian marine mammal fauna evolved relatively recently in the Pleistocene. With sustained research effort and field exploration, the Australian fossil record will yield significant new data on the evolution of marine mammals.
THE LATE OLIGOCENE MARINE MAMMAL ASSEMBLAGE OF THE SAN JUAN AND TIMBABICHI MEMBERS (EL CIEN FORMATION), BAJA CALIFORNIA SUR, MEXICO Gerardo Gonzalez Barba Departamento de Biologia Marina y Museo de Historia Natural, Universidad Autonoma de Baja Califbmia Sur, La Paz, Mexico, gerardofaHiabcs.nix Key words: Late OUgocene Marine Mammals, El Cien Formation, Baja Cahfomia Sur, Mexico. The name El Cien Formation has been applied in the 1980s to Late Oligocene - Early Miocene marine and terrestrial sediments cropping out in the area of the El Cien (between San Hilario and Cerro Colorado area), on the Pacific margin of the Isthmus of La Paz. Until the early 1990s, the San Juan Member was formally named cropping out in the San Juan de la Costa - La Animas area (in the middle part of the Bay of La Paz), and the El Aguajito - La Fortuna area on the Pacific margin. The Timbabichi member was formally named in 2002, for the outcrops in the Timbabichi - Punta San Carlos (or San Telmo) area. The marine mammals occur throughout both members, mainly from the phosphatic sandstones (mid-platform storm deposits), pelagic shales and mudstones, and even in reworked coastal conglomerates. Most of the skeletal remains were collected from surface and mine spoils; they are usually represented by isolated or associated elements and articulated squeletons. The fauna includes: Balaenidae (primitive tooth-bearing Mysticetes), Aetiocetidae (toothed Mysticetes), Cetotheridae (primitive baleen-bearing Mysticetes), an unnamed family (primitive baleen-bearing Mysticetes), Agorophidae (primitive toothed whales), Waipatiidae (primitive toothed whales), and Desmostylidae {Cornwalius sookensis) represented by an isolated tooth. These remains have been reported since the 1940s from the Punta San Telmo (Timbabichi Member). Most of the specimens are still in the enclosing rock stored at the MHN-UABCS. The assemblage record from Baja Cahfomia Sur is the only one for the Ohgocene in Mexico and its paleobiogeographical implications in regard to the global record are not yet solved.
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THE DIVERSITY AND STRATIGRAPHIC DISTRIBUTION OF CETACEANS IN EARLY CENOZOIC STRATA OF WASHINGTON STATE, U. S. A. James L. Goedert\ Lawrence G. Barnes^ and Hitoshi Furusawa^ ^Burke Museum, University of Washington, Seattle, Washington, 98195, USA, i goedeit@u.Washington.edu: ^Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California, 90007, USA; ^Sapporo Museum Activity Center, Linkage Plaza, N1W9 Sapporo, Hokkaido, 060-0001, Japan Key words: Eocene, Oligocene, mysticete, odontocete Cenozoic deep-water marine strata of western Washington State, U.S.A., preserve an unrivaled evolutionary record of eastern North Pacific latest Eocene to Early Miocene cetaceans. Large collections have been made and they notably include the Oligocene tooth-bearing mysticete Chonecetus goedertorum Barnes and Furusawa (Barnes et al, 1995), and the world's earliest known odontocete (Barnes et al, 2001). The geochronologic ages for many of these specimens are often cited as suspect, or 'poorly constrained', particularly when they are older than similar taxa from elsewhere. Mollusks and foraminiferans from deep-water strata of Washington have posed problems for biostratigraphers because of provincialism and time-transgressive zonal boundaries; however, recent magnetostratigraphic work has greatly helped with long distance stratigraphic/age correlations. Archaeocetes have not yet been found. A baleen-bearing mysticete was present in the eastern North Pacific by latest Eocene time, and archaic but specialized odontocetes were present by Early Oligocene, along with larger cetaceans, possibly mysticetes. Before latest Oligocene time, cetacean assemblages typically included several kinds of smallbodied tooth-bearing mysticetes, moderately large baleen-bearing mysticetes, and four or more kinds of archaic odontocetes with various rostral morphologies and orbit sizes. Late Oligocene assemblages include both tooth-bearing and baleen-bearing mysticetes, but a decreased abundance and diversity of archaic odontocetes. By Early Miocene time, in contrast, more derived groups of odontocetes were abundant, but mysticetes were very rare, and tooth-bearing mysticetes had disappeared. The observed changes in taxonomic diversity may be Unked to changes in paleobathymetry. BARNES, L.G., KIMURA, M., FURUSAWA, H., & SAWAMURA, H., 1995. Classification and distribution of Oligocene Aetiocetidae (Mammalia; Cetacea; Mysticeti) from western North America and Japan. The Island Arc 3, 392-431. BARNES, L.G., GOEDERT, J.L., & FURUSAWA, H., 2001. The earliest known echolocating toothed whales (Mammalia; Odontoceti): Preliminary observations of fossils from Washington State. Mesa Southwest Museum Bulletin 8, 91-100. PELAGIC HABITAT PREFERENCE IN THE ORIGIN OF THE OTARHD PINNIPEDS Naoki Kohno Department of Geology and Paleontology, National Museum of Nature and Science, 3-23-1 Hyakunincho, Shinjuku-ku, Tokyo, 169-0073 JAPAN, kohno@kahaku.go.jp Key words: Pinnipedia, Otariidae, initial habitat preference, pelagic The fur seals and sea lions of the family Otraiidae (Camivora: Pinnipedia) are represented in the Recent fauna of both the northern and southern hemispheres. Most of the taxa within the Otariidae are recognized as nearshore inhabitants inheriting the primitive condition for the pinnipeds. However, the northern fur seals are considered to have acquired pelagic habitats, as did the cetaceans. Interestingly, specimens of the earliest otariid from the late Middle Miocene and some early otariids from the Late Miocene of the western North Pacific have depositional environments that are regarded roughly as bathyal. This suggests that ^the habitat preference of the early otariids was mainly the pelagic ocean, except for the breeding season. The pelagic habitat of the northern fur seals has generally been regarded as an ecological trait that was secondarily derived from the nearshore ancestral otariids. However, evaluation of the habitat preference of 44
the ancestral otariids within a phylogenetic context suggests that the pelagic existence is more likely the ancestral condition for the otariids, and nearshore habitats among sea lions and southern fur seals may be regarded as secondary. This ecological shift may coincide with the change of the dietary preference of the odobenine walruses from nearshore piscivory to inshore mollluskivory during the late Late Miocene. If these hypotheses are correct, migration and diversification of sea lions and southern fur seals may have occurred after the re-acquisition of the nearshore habitat during the late Late Miocene.
CONSIDERATIONS ON THE ECOLOGY OF FOSSIL SPERM WHALES Oliver Hampe Museum fiir Naturkunde der Humboldt-Universitat zu Berlin, Invalidenstrafie 43, D-10115 Berlin, Germany, email: oliver.hampe@museum.hu-berlin.de Key words: Hoplocetinae, dentition, feeding, stratigraphy The living sperm whale (Physeter macrocephalus) is the largest of all toothed whales and is adapted to deep diving and feeding on deep sea squid; demersal and mesopelagic fish play here a minor role. The sperm whale has conical teeth in the lower jaw which do not seem to be necessary for feeding, as they do not erupt until near puberty (Whitehead 2002). Rudimentary upper jaw teeth rarely erupt and are without function. Several fossil sperm whales are equipped with both functional upper and lower teeth. Recently investigated teeth of a hoplocetinid sperm whale {Hoplocetus ritzi) from the uppermost Middle Miocene of North Germany exhibit a high degree of abrasion (Hampe 2006). Existing enamel caps of these fossil representatives are abraded and dentine parts are often chipped off during life by contact between the antagonistic tooth pairs. That indicates a highly predatory nature of this taxon, as is also considered to be the case for other representatives of this fossil group. It appears to be quite similar to that observed in modem killer whales, the opportunistic top predators of today with their interlocking teeth adapted for ripping and tearing. However, the Orcininae occur late in earth's history and are not known before the middle Pliocene. The extinct Hoplocetinae which disappeared during the Pliocene possibly occupied the killer whale niche before the orcinine dolphins appeared. HAMPE, O., 2006. Middle/late Miocene hoplocetine sperm whale remains (Odontoceti: Physeteridae) of North Germany with an emended classification of the Hoplocetinae. Fossil Record 9(1), 61-86. WHITEHEAD, H., 2002. Sperm Whale. In Encyclopedia of marine mammals, PERRIN, W.F., WURSIG, B.& THEWISSEN J.G.M., eds.. Academic Press, San Diego, 1165-1172.
DISCOVERIES OF SIRENIAN REMAINS FROM THE EARLY OLIGOCENE OF THE RHINERUHR AREA (GERMANY) AND A NEW LOOK ON THE GENUS HALITHERIUM Manja VoC Museum fur Naturkunde der Humboldt-Universitat zu Berlin, Invalidenstrafie 43, D-10115 Berlin, Germany, manja.voss@museum.hu-berlin.de Key words: Halitherium, Oligocene, Germany, morphotypes At present, two species of Halitherium are regarded as valid within the European Oligocene, H. schinzi Kaup 1838 (from the early Oligocene of Europe) and H. christoli Fitzinger 1842 (from the late Oligocene of Upper Austria). Both taxa show great intraspecific variability. In addition, the differences between H. schinzi and H. christoli are minimal (Abel 1904). A specific allocation of four disarticulated and incompletely preserved Sirenia skeletons from the early Oligocene of the Rhine-Ruhr area was accordingly difficult. A partial skeleton from Duisburg could undoubtly be assigned to Halitherium schinzi based on significant correspondence in the shape of the taxonomically very important cranial elements, like supraoccipital and 45
zygomatic processes. Two further fragmentary finds from Ratingen, near Diisseldorf, were classified as representatives of the genus Halitherium. None of these two fossils could be assigned to one of the known species because of the incompleteness of the material. Despite its fragmentary preservation, a partial skeleton from Bottrop, Mixnsterland, unites characteristics of Halitherium schinzi from the Mainz Basin and the Belgian Oligocene and H. christoli, H. abeli and H. pergense from the late Oligocene of Upper Austria. However, the Bottrop specimen shows also individual characteristics. The described Halitherium remains show that the genus was more frequent than expected so far and consists probably of further species. The Duisburg specimen shows that Halitherium schinzi in particular was not limited to the Mainz Basin. ABEL, O., 1904. Die Sirenen der mediterranen Tertiarbildungen Osterreichs. Abhandlungen der Kaiserlich-Koniglichen Geologischen Reichsanstalt 19(2), 1-223. ORIGIN AND DISTRIBUTION OF A LARGE SIRENIAN, HYDRODAMALIS Hitoshi Furusawa Sapporo Museum Activity Center, Linkage Plaza, N1W9, Sapporo, 060-0001, Japan hitoshi.furusawa@city.sapporo.jp Key words: Sirenia, Hydrodamalis, Miocene, North Pacific Ocean Although most of the Sirenia inhabit waters of mild temperature, the subfamily Hydrodamalinae was uniquely adapted to cold temperatures. They expanded their distribution throughout the North Pacific Ocean, dependent upon the continuous shallow water areas available due to low sea levels caused by global climatic changes. The large body size is a character of adaptation to cold; the body length of the genus Hydrodamalis ( 1 0 m) nearly twice the size of the genus Dusisiren (4-^5 m). Phylogenetic analyses show that the genus Dusisiren is the ancestor of the genus Hydrodamalis. Increase in overall body size occurred in the Late Miocene in the eastern North Pacific and during Early Pliocene time in the western North Pacific. However, a definite age for the transition from Dusisiren to Hydrodamalis was not known until the discovery of the Sapporo sea-cow in 2003. An isotopic age for the specimen (8.2±0.3 Ma) was obtained from volcanic ash beneath the fossil using the F.T. method. Microfossils (diatoms, foraminiferans, radiolarians, calcareous nannoplankton, fossil pollen) associated with the fossil support this result. Moreover, another specimen of the genus Dusisiren was discovered in the same diatom fossil zone at Numata about 100 km northeast of Sapporo. Thus, the Sapporo sea-cow is from the appropriate time to show the transition from the genus Dusisiren to the genus Hydrodamalis. Apparently, the increase in body size of both genera occurred simultaneously, at least in the North Pacific, or there is the possibility that the enlargement of the body size occurred first in the westem North Pacific and then spread throughout the North Pacific. Also, it is now clear that the increase in body size was not coincident with a period of severe cold in global climatic changes. TAKING THE MYSTERY OUT OF TOOTHED MYSTICETES: PHYLOGENY AND EVOLUTION OF STEM-GROUP MYSTICETI (CETACEA) Erich M.G. Fitzgerald School of Geosciences, Monash University, VIC 3800, Australia; Museum Victoria, GPO Box 666, Melbourne, VIC 3001, Australia efitzger@museum.vic.gov.au Key words: Cetacea, Mysticeti, phylogeny, evolution 46
At one time or another several cetacean taxa have been referred to as 'toothed archaic mysticetes', including Llanocetus denticrenatus, Mammalodon colliveri, Janjucetus hunderi, various taxa referred to the family Aetiocetidae, and undescribed forms from South Carolina. Determination of the phylogeny of these stem mysticetes underpins any attempts to interpret broader patterns and processes of evolution. Here I report results of phylogenetic analyses using parsimony. Salient features of the most parsimonious hypothesis include: SCTM forming the basal clade within a stem-based Mysticeti, with other toothed mysticetes branching in the crownward orAqx Janjucetus, Mammalodon, Chonecetus sookensis, NMV P216928 (an undescribed toothed mysticete from Australia), Llanocetus; and a monophyletic Aetiocetidae (Aetiocetus cotylalveus and Chonecetus goedertorum + Aetiocetus polydentatus) being sister to Chaeomysticeti (toothless baleen whales). This preliminary study implies that: (a) several toothed mysticete clades have significant ghost lineages; (b) mysticetes diverged from other cetaceans and radiated prior to 34 Ma; (d) Aetiocetidae sensu lato is perhaps paraphyletic; and (e) within aetiocetids, Chonecetus and Aetiocetus are probably paraphyletic genera. While this study suggests the broad pattern of toothed mysticete evolution, the interrelationships of most toothed mysticetes must be regarded as unresolved, pending analysis of key undescribed specimens and revision of named taxa; this is especially so for Aetiocetidae, with many taxa based on rather incomplete specimens lacking crucial anatomical details. Toothed mysticetes were clearly both diverse and disparate, evidencing complexity in the transition from toothed to toothless mysticetes. These and other problems will be highlighted along with directions for future research. OLDEST EUBALAENA FROM THE GONDA FORMATION (LATEST MIOCENE-EARLY PLIOCENE), JAPAN AND ITS IMPLICATION FOR THE EVOLUTION OF RIGHT WHALES Toshiyuki Kimura and Yoshikazu Hasegawa Gunma Museum of Natural History, 1674-1 Kamikuroiwa, Tomioka, Gunma 370-2345, Japan, kimiira@giTinh.pref.gurima.ip
Key words: Balaenidae, Eubalaena, latest Miocene-Early Pliocene, Japan In 1938, a mysticete fossil was recovered from the Gonda Formation (latest Miocene-Early Pliocene) of Japan. The specimen includes a skull and a lumbar vertebra. Several authors have reported this specimen as Balaenidae gen. et sp. indet., but the specimen has not yet been formally described and/or diagnosed. It is characterized by having a large skull (CBL: 3996mm) with highly arched and transversely compressed rostrum, distinct angled apex between rostral and cranial bones, wide ascending process of maxilla, parietal spreading onto supraorbital process of frontal, low temporal crest on supraorbital process of frontal, and a domed supraoccipital. Based on the above combination of characters, the specimen is placed in the genus Eubalaena. Other characters indicate that this is a relatively archaic member of the genus, including elongated nasal and relatively less arched curvature of the skull. The geologically oldest known fossil of Eubalaena was found in the Early Pliocene (c. 3.5-3.3Ma) of Italy. The Joshita Formation, which overlies the Gonda Formation, intercalates Kumeji pyroclastics. The geological age of Kumeji pyroclastics was determined as 4.2±0.3 Ma by K-Ar dating, and this suggests that the specimen from Gonda Formation is the oldest record of Eubalaena ever discovered. The genetic distinction of living genera of right whales is controversial, with some authors suggesting that all hving right whales belong to the single genus, Balaena. However, the specimen described here suggests a long independent history of Eubalaena and Balaena. This specimen also indicates that balaenids developed a highly specialized skim feeding mechanism by the Early Pliocene. THE SYSTEMATICS AND BIOGEOGRAPHY OF RIGHT WHALES (BALAENIDAE: MYSTICETI) Morgan Churchill Annalisa Berta ^ and Thomas Demere ^ Department of Biology, San Diego State University, 5500 Campanile Dr., San Diego CA 92182-4614, USA, inorganxhurchjll-@gmail.com: ^ San Diego Natural History Museum, 1788 El Prado, San Diego CA 92101, USA 47
Key words: Balaena, Balaenidae, biogeography, Eubalaena Right whales are baleen-bearing whales represented by four modem species, the arctic bowhead, Balaena mysticetus, and three species of the temperate right whale, Eubalaena. Despite a limited diversity during the Holocene, right whales were common and speciose elements of Pliocene marine mammal faunas. However, the phylogenetic affinities of fossil right whales still remain uncertain. This study incorporates 25 taxa representing all major clades of living and fossil baleen whale and 118 morphological characters of the cranium and post-cranium in a phylogenetic analysis of fossil and extant balaenids. Idiocetus guicciardinii is found to belong to Balaenidae incertae sedis. The fossil taxon Morenocetus parvus is recovered as the earliest diverging right whale, and two major clades of right whale are recognized. These clades include a poorly supported Balaenula clade, and a "crown" right whale clade, composed of two monophyletic groups, a Balaena-Balaenella clade, and a Eubalaena clade. For the first time in a morphological study, E. glacialis is supported as sister to E.japonica and E. australis. Relationships within Balaena remain unresolved. The biogeography of right whales was investigated using the computer program DIVA, molecular clock data, and the fossil record. Balaenids are shown to have originated in the Southern Hemisphere, and then later dispersed into the Northern Hemisphere. Eubalaena likely originated in the North Atlantic, with subsequent dispersals to the southern oceans then to the North Pacific, during Pleistocene glacial maximums. Though mostly undescribed, balaenids were common components of Pliocene North Pacific marine mammal faunas
NEW SHARK-TOOTHED DOLPHIN (LATE OLIGOCENE, NEW ZEALAND) ELUCIDATES THE EARLY HISTORY OF THE EXTINCT SQUALODONTIDAE R Ewan Fordyce Department of Geology, University of Otago, Dunedin, NZ 9054. cwan.fordyce@stonebow.otago.acjiz Key words: Cetacea, systematics, extinction, Platanistoidea Squalodontids are extinct, long-jawed, shark-toothed dolphins first reported from marine rocks of Europe, and known from the Atlantic and Pacific margins including New Zealand and Australia. Squalodontids thrived from Late Oligocene to Middle Miocene, leaving no apparent ecological equivalent amongst living dolphins. An unnamed Late Oligocene species from New Zealand helps to understand the early history of the group. Material includes an associated skull, mandibles, teeth, tympano-periotics, vertebrae, ribs and part of a forelimb (OU22457, Geology Museum, University of Otago), from the Milbum Limestone, South Otago. Notable features are: teeth heterodont, polydont, emergent; teeth procumbent and conical anteriorly, denticulate and rugose posteriorly, with 11 postcanines; posterior teeth lack diastemata and, in maxilla, have a third lingual root; rostrum and skull are robust, temporal fossae large; short wide nodular nasals roof large olfactory cavity; frontals large medially; crushed basicranium has complex topography and foramina around periotic; cervicals unfused; scapula has prominent acromion but no coracoid process (supporting Muizon's placement of squalodontids in the stem Platanistoidea). Although the dolphin was not old (vertebral epiphyses are clear), teeth are worn, suggesting a snapping durophagous diet. Skull features suggest that the dolphin was an echolocator. The species is distinct from other squalodontids known from New Zealand CProsqualodon'' hamiltoni, and 3-4 other unnamed species) and Austraha {Prosqualodon davidis). Some tooth and periotic features appear intermediate between Prosqualodon (socalled Prosqualodontidae) and Squalodontidae, blurring supposed family distinctions. Whether Squalodontidae belong in Platanistoidea and in crown-Odontoceti, or in a basal cluster of stemOdontoceti, is debatable
48
PLIOCENE CLIMATE CHANGE AND GENETIC DIVERGENCE AMONGST SOUTHERN AUSTRALIAN BOTTLENOSE DOLPHINS (TURSIOPS SP.) K. Charlton ^ School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia; ^ Australian Centre for Biodiversity: Analysis, Policy and Management, School of Biological Sciences, Monash University, Clayton,, Victoria 3800, Australia; ^ Centre for Environmental Stress and Adaptation Research (CESAR) School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia; kate.charlton@sci.monash.edu.au Key words: Tursiops, Pliocene, mitochondrial DNA, divergence Bottlenose dolphins {Tursiops sp.) have a global distribution throughout tropical and temperate waters, both inshore and offshore, and exhibit regional morphological and genetic variation. Current genetic data strongly suggest that the 'inshore' southern Australian bottlenose dolphin {Tursiops sp.) is unique, long isolated and possibly locally adapted. The level of divergence (5.2%) observed between the 'inshore' dolphin to it's nearest known relative, T. truncatus found in offshore waters, strongly suggests that this unique 'inshore' dolphin represents a new sub/species that is restricted to southern Australian waters. By combining current genetic technologies with our knowledge of historic environmental changes we can hypothesize where and how this unique population may have arisen. The rate of mtDNA control region divergence in cetaceans has been estimated at between 0.5-1% per million years, placing the time of species split from the earliest known relative, at 2.6-5.2 million years ago. The extant genus, Tursiops, has mid Pliocene records with the earliest collected Tursiops fossil from western Victoria (Portland) dating between 2.5 and 4.5 million years old, thus placing Tursiops species in this region during the estimated time of split. There are reports of several warming periods within the Pliocene epoch, possibly creating habitat for radiating dolphin species.The Gippsland and Bass Basin is of significant interest, as possible niches during warmer Pliocene periods, for the establishment of coastal founder populations. The extensive genetic divergence of the southern Australia 'inshore' dolphin and the long-term isolation that this implies can now be investigated by linking 'molecular clocks' to historical environmental events.
TAXONOMY OF BOTTLENOSE DOLPHINS: ARE WE ON THE RIGHT TRACK? Catherine Kemper^ and Peter Hale^ ^ South Australian Museum, North Terrace, Adelaide, South Australia 5000, Kempcr.Catb@saugov,sa.gov.au; ^Ecology Centre, University of Queensland, Queensland 4072 Key words: Bottlenose dolphins, taxonomy, osteology, modem species Bottlenose dolphins are amongst the more conservative of the living species in the rapidly evolving Family Delphinidae. Their body form, osteology and diet are generalist in nature. Two species of bottlenose dolphin are recognised: Tursiops truncatus occurs in all major temperate and tropical oceans; T. aduncus is apparently restricted to habitats adjacent to land masses in the Southern Hemisphere and western north Pacific Ocean. Regional osteological studies have concluded that rostral features are important in discriminating these species but as yet there has been no worldwide comparison that describes their intraspecific variation. Genetic studies suggest that there is substantial substructure within T. aduncus throughout its range and that some populations may be more closely related to Delphinus than to T. truncatus. To date, there is no corroborating morphological evidence for these genetic relationships. Recent osteological and genetic studies of a large number of bottlenose dolphin specimens in South Australia have distinguished T. aduncus, primarily in protected waters, and T. truncatus, from the oceanic zone. There is evidence of morphological intermediates along the oceanic coast and genetic mixing between species. The skull shape of T. aduncus appears more 'juvenile' with increasing distance from the oceanic environment. The South Australian Museum's large and comprehensive collection of bottlenose 49
dolphin specimens from this unique region provides the key to investigating evolutionary processes, including the possible influence of heterochrony and neoteny, in the genus Tursiops.
SKULL MORPHOLOGY OF ATLANTIC SPOTTED DOLPHINS, Stenella frontalis (CUVIER 1829), IN BRAZIL: COMPARISONS BETWEEN NORTH ATLANTIC AND CARIBBEAN POPULATIONS Ignacio Benites Moreno Grupo de Estudos de Mamiferos Aquaticos do Rio Grande do Sul (GEMARS) & Centro de Estudos Costeiros, Limnologicos e Marinhos (CECLIMAR/UFRGS) Rua Felipe Neri, 382 conj 203, Porto Alegre, RS, 90440-150, Brazil; Laboratorio de Ictiologia, (MCT, PUCRS), Av. Ipiranga, 6681, Caixa Postal 1429, Porto Alegre, RS, 90619-900, Brazil; Present address: Department of Geology, University of Otago, New Zealand, IeHv.moreno@CTailcom Key words: Geographic variation, morphology. South Atlantic Ocean, Stenella The Atlantic spotted dolphin, Stenella frontalis, is endemic to the Atlantic Ocean. In the southwestern Atlantic the distribution of S. frontalis was properly described only recently (Moreno et al. 2005). In this region, S. frontalis is found only in continental shelf waters in two regions, north of 6°S and between 21° and 33°S, indicating a discontinuous distribution along the eastern coast of the South American continent. A large geographical variation is recognized in this species. In this work, a comparative analysis of skull morphology and morphometries between adult dolphins collected off southem and southeastern Brazil (n=31) and in the North Atlantic Ocean and Caribbean (n=35) was carried out. This study revealed differences in the skull morphology between different populations of spotted dolphins. Thirteen out of the 36 skull measurements differed significantly (p<0,05; t test) between North Atlantic/Caribbcan and southwestern Atlantic populations. Although overlap exists, the southwestern Atlantic animals have on average three more teeth in each tooth row than the North Atlantic animals and these differences are significantly different (p=<0,001; Mann-Whitney test). Principal component analysis (PCA) of the two first relative warps (geometric morphometries) revealed two main groups in accordance with the data based on skull measurements/meristics. The differences in skull characteristics and the discontinuous distribution in the South Atlantic indicate that the "southwestern Atlantic population" is likely geographically and reproductively isolated. Due to its unknown status, further studies (e.g. abundance, mortality and genetics) should be viewed as a priorit}^ to assess the conservation status of this distinct population. Financial Support: CNPq, CAPES, Society for Marine Mammalogy, Cetacean Society International, The Humane Society of The United States. MORENO, LB., et al 2005. Distribution and habitat characteristics of dolphins of the genus Stenella (Cetacea: Delphinidae) in the southwest Atlantic Ocean. Marine Ecology-Progress Series 300, 229-240.
DENTAL STRUCTURE AND WEAR IN THE DESMOSTYLIA AND SIRENIA Brian L. Beatty Department of Anatomy, New York College of Osteopathic Medicine, Northern Boulevard, Old Westbury, NY 11568, USA, bbeattv@nvit.edu Key words: Occlusal geometry, dental microwea, Sirenia, Desmostylia Aspects of tooth structure, occlusal geometry and dental microwear were investigated in Miocene Sirenia and Desmostylia to better understand their feeding, and hence, resource partitioning during this period of extreme sympatric diversity. Seagrasses are mechanically similar to terrestrial grasses and ingested with homy pads or tusks using tensile fracture. Rostral deflection is associated with feeding on seagrasses in all the Sirenia, but not the 50
Desmostylia, reflecting their lack of hydrostatic constraints. Tusk tip microwear and geometry indicates that some tusks had blade edges (i.e. Corystosiren, Rytiodus, and Dioplotherium) for cutting woody rhizomes with high fracture toughness, and some were probes {Metaxytherium, Desmostylus, Paleoparadoxia) more suited for uprooting less tough rhizomes. Dental microwear on the lingual surfaces of cheek teeth in the Desmostylia indicates abrasion by substrate particles between the tongue and teeth like lingual piston suction feeding of Odobenus. Most sirenian enamel microstructure is horizontal HSB for resisting damage from shearing. Modified radial enamel in Desmostylus hesperus and vertical HSB-like microtopography of Metaxytherium enamel were adaptations for resisting vertical loading of hypsodonty or increasing coefficient of friction. The fovea apicis tuberculi dentis of desmostylian teeth is found in adult teeth of Desmostylus and Paleoparadoxia and provided rapid exposure of the DEJ, enhancing shearing ability. Functional occlusal surface area is allometric to shear length for Desmostylus due to enamel thickness. Dental microwear indicates that trichechid diets are more abrasive (and masticated) than dugongid and desmostylian diets. Scratch orientation supported transverse jaw motions in Sirenia and protraction/retraction jaw movements in Desmostylus.
NEW INSIGHTS INTO THE EVOLUTIONARY BIOLOGY OF MYSTICETE CETACEANS Annalisa Berta\ Thomas A. Demere^, Michael R. McGowen^'^ and John G. Gatesy3 ^Department of Biology, San Diego State University, San Diego, CA 92182, USA aberta@sunstroke.sdsu.edii; ^Department of Paleontology, San Diego Natural History Museum, San Diego, CA 92112, USA; ^Department of Biology, University of California, Riverside, CA 92521,US A. Key words: supermatrix, phylogeny, teeth-baleen transition We report newly generated morphological and molecular data for mysticete phylogeny that includes 35 fossil and extant taxa and >27, 000 (3,570 parsimony informative) characters. Several well substantiated relationships emerge from our analysis including a basal division of a monophyletic Mysticeti into paraphyletic toothed mysticetes and an edentulous clade. A monophyletic, taxonomically diverse Aetiocetidae is supported as is the newly described Janjucetus sister to Mammalodon + Aetiocetidae. The edentulous clade is comprised of eomysticetids and later diverging mysticetes. The relationship of "cetotheres" remains problematic; they were excluded from the crown group Mysticeti but in another slightly less parsimonious arrangement grouped within extant Mysticeti. Within Mysticeti, several clades are supported by the supermatrix analysis including: Balaenidae, Megaptera novaeangliae + Balaenoptera physalus, B. borealis + B. edeni/B. brydei. The combined data set was used to reconstruct the sequence and timing of the transition from teeth to baleen in mysticetes. Phylogenetic analysis supports a stepwise transition in the late Oligocene (29-24 mya) from a toothed ancestor (i.e. Janjucetus) to a mosaic intermediate with both teeth and baleen (i.e. aetiocetids), to modem baleen whales (i.e. later diverging mysticetes) that lack an adult dentition but retain genetic and developmental evidence of their ancestral toothed heritage. Since baleen whales lack a mineralized dentition but were derived from toothed ancestors we predicted that enamel-specific genes (i.e. ameloblastin and enamelin) would be present in the mysticete genome but would be non-functional. This prediction was bome out for these dental genes that contained frameshift mutations preventing normal tooth development.
RECONSTRUCTING BODY SIZE IN EXTINCT CROWN CETACEA USING ALLOMETRIC SCALING, PHYLOGENETIC COMPARATIVE METHODS, AND TESTS FROM THE FOSSIL RECORD Nicholas D. Pyenson^'^ and Simon Sponberg^ ^Department of Integrative Biology, University of California, Berkeley, CA 94720, USA, pvenson@bcrkelev.edu: ^University of California Museum of Paleontology, 1101 Valley Life Sciences Building, Berkeley, CA 94720, USA 51
Keywords: Body size, comparative methods, Cetacea, fossil record Living cetaceans exhibit interspecific size ranges that span several orders of magnitude, and they rank among the largest vertebrates of all time. The details of how cetaceans evolved such large body size, however, remain obscure because of the lack of a good size proxy. Body size in fossil mammals has been estimated using dental and limb proxies, but such values are uninformative because cetaceans lack weightbearing limbs and have derived dentition. Here, we reconstruct the body size of extinct crown group cetaceans (Neoceti) using different regression methods on extant skull and length data in a phylogenetic context. Because most fossil cetaceans are represented by isolated cranial remains and very few specimens preserve total length, we developed regression equations to predict total length based on key cranial metrics that can be easily found on fossil crania. These equations are based on a database of skull and length data from extant lineages of cetaceans (n = 44 sp.), including all living mysticete genera and all key clades of odontocetes. To generate predictive equations, we used both classic regression methods and a new approach that combines the advantages of canonical multivariate methods with independent contrasts to account for phylogenetic effects. Lastly, we used the rare occurrences of fossil taxa with preserved total lengths to test our predicted lengths using only skull measurements. Our results demonstrate that incorporating phylogenetic relationships in scaling studies can increase the accuracy of reconstructed body size and provide a way of examining body size distributions of cetaceans through time.
Posters: Early Vertebrates and General Sessions GEOMETRIC MORPHOMETRIC SHAPE QUANTIFICATION USING ELLIPTICAL FOURIER ANALYSIS: AN EXAMPLE FROM HUMAN FRONTAL SINUS SHAPE AND POTENTIAL USE IN COMPARING PALAEONTOLOGICAL REMAINS Greg P. Bell Department of Earth & Marine Sciences, ANU, Canberra, ACT 0200, greg_bell82@yahoo.com.au Key words: Geometric Morphometries Placoderm Fishes A recent study by Bell (2006) evaluated the heritability of the human frontal sinus area and shape in related individuals using Elliptical Fourier Analysis (Kuhl & Giardina 1982) and area measurements. Frontal sinus area was found to be significantly similar between siblings, and in future studies with area left in as a variate in the computation of Fourier coefficients, frontal sinus shape similarities between family members are likely to be significant also, holding great potential for the study of famihal kinship in mortuary archaeology and the investigation of mass graves and crimes against humanity. Geometric morphometric techniques, such as Elliptic Fourier Analysis (EFA) which extract geometrical information from biological shape for comparative purposes (Bookstein 1982), may be applied to accurately assess and quantify shape similarities and differences between individuals, populations and both extant and extinct species as shown in previous studies (Sengupta et al 2005; Kassam et al 2004). The use of EFA to distinguish between populations and species in a palaeontological context is explored using Late Devonian placoderm fishes from New South Wales. BELL, G.P., 2006. Human Frontal Sinus Shape and Area Correlations between Related Individuals: Quantification and Implications. (Honours Thesis). Australian National University: Canberra. BOOKSTEIN, F.L., 1982. Foundations of Morphometries. Annual Review of Ecology and Systematics 13,451-470. KASSAM, D., MIZOIRI, S., & YAMAOKA, K., 2004. Interspecific variation of body shape and sexual dimorphism in three coexisting species of the genus Petrotilapia (Teleostei: Cichlidae) from Lake Malawi. Ichthyological Research 51, 195-201. KUHL, F.P., & GIARDINA, C.R., 1982. Elliptic Fourier features of a closed contour. Computer Graphics and Image Processing 18, 236-258. SENGUPTA, D. P., SENGUPTA, D. & GHOSH, P., 2005. Bilaterally symmetric Fourier approximations of the skull outlines of temnospondyl amphibians and their bearing on shape comparison. Journal of Biosciences 30, 377-390. 52
A NEW FRESHWATER FISH (TELEOSTEI: ICHTHYODECTIFORMES) FROM THE MIDCRETACEOUS (ALBIAN-CENOMANIAN) WINTON FORMATION OF ISISFORD, CENTRAL-WESTERN QUEENSLAND, AUSTRALIA Rodney W. Berrell\ Steven W. Salisbury^'^ and Yoshitaka Yabumoto^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia, s413 S223@stiident>uq>eclu,au: ^Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA; ^Kitakyushu Museum of Natural History and Human History, 2-4-1, Higashida, Yahatahigashiku, Kitakyushu, Fukuoka, 805-0071, Japan Key words: Ichthyodectiformes, Winton Formation, Cretaceous, Queensland Despite its vast geographic expanse and the environmental regime under which its sediments were deposited, the mid-Cretaceous (latest Albian-earliest Cenomanian) Winton Formation of central-western Queensland has produced very few fossils of freshwater fishes. To date, the only described specimens belong to two species of ceratodont lungfish. In 2005, a new freshwater fish fossil was discovered in the rocks of the Winton Formation near the town of Isisford, central-western Queensland. The specimen was found at the same locality that produced the paratype skull of the basal eusuchian crocodylomorph Isisfordia duncani, and represents the second freshwater fish from the Isisford fauna. It is preserved as part and counterpart in a football-sized nodule of weakly laminated, fluvial, volcanoclastic sandstone. The skeleton is preserved in articulation, and includes a complete skull and the anterior half of the body. Scales impressions are also visible on the counter part. Preliminary studies indicate that this species belongs to the order Ichthyodectiformes. Although now extinct, these large, mackerel-like predatory basal teleosteans are known from Middle Jurassic to Upper Cretaceous. The Isisford specimen represents the first freshwater ichthyodectiform from Australia. Further preparation of the specimen is required before comparisons can be made with other marine ichthyodectiforms from Queensland, such as Cooyoo australis and Pachyrhizodus marathonensis from the Albian Toolebuc and Allaru formations. The discovery of a freshwater ichthyodectiform at Isisford hints at the hidden diversity of this group in the Australian Cretaceous.
ONTOGENY OF THE SKULL OFNIMBADONLAVARACKORUM, A MID MIOCENE ZYGOMATURINE (DIPROTODONTIDAE, MARSUPIALIA) FROM RIVERSLEIGH, NORTHWESTERN QUEENSLAND Karen Black School of Biological, Earth & Environmental Sciences, The University of New South Wales, Sydney, NSW 2052, Australia, k.black@unsw.edu.au Key words: Ontogeny, Allometry, Diprotodontoid, Vombatomorphia Near complete juvenile and subadult crania for Nimbadon lavarackorum have been recovered from the mid Miocene AL90 Site, Riversleigh World Heritage Fossil Deposits, northwestern Queensland. Fifteen skulls and 14 dentaries/mandibles ranging in age from pouch young to aged adults are represented in the sample. Because absolute ages of individuals could not be determined, arbitrary definitions for their relative stage of development were established based on the number of teeth erupted, their state of wear, and the visibility/fusion of cranial sutures and the mandibular symphysis. Qualitative morphological changes from the juvenile crania to the adult condition are described. In addition, thirteen cranial and six mandibular measurements were analysed using Reduced Major Axis regression to study allometric growth. Most notable differences between adult and juvenile crania were found to be related to the development of structures (e.g. crests, processes, fossae etc) for the insertion of the masticatory muscles and reflect a change in diet from primarily suckling to mastication. Further, in juvenile crania, the facial cranium is developmentally more advanced (proportionately larger and better ossified) than the basicranium, a condition found in all extant juvenile marsupial skulls, and related to the functional requirements (i.e. suckling, teat attachment) of the neonate marsupial (Clark & Smith, 1993). 53
CLARK, C.T. & SMITH, K.K., 1993. Cranial osteogenesis in Monodelphis domestica (Didelphidae) and Macropus eugenii (Macropodidae). Journal of Morphology 215, 119-149. POSTCRANIAL EXO- AND ENDOSKELETON - NE'ER THE TWAIN SHALL MEET, OR...? Carole J. Burrow Queensland Museum, 122 Gerler Road, Hendra, QLD 4011, Australia, palaeoicli@vahoo.com.au Key words: Cartilage, Placodermi, Osteostraci, Sinacanthidae Despite the traditional view that exo- and endoskeletons are absolutely separate, fused dermal and chondral bones occur in modem and fossil fishes. I suggest that an association of dermal bones and endoskeletal cartilage, often with perichondral bone, is a general rather than a special character in the cranial and postcranial skeletons of early jawed fish. Osteostracan agnathans, currently regarded as a sister group of gnathostomes, had a cartilaginous endoskeleton lined internally with perichondral bone which covered the braincase, branchial region and pericardic cavity and was continuous with the endoskeletal shoulder girdle; its outer surface was fused to the dermal bone shield and plates (Janvier 2001). Placoderms are the sister group of all other gnathostomes, and antiarchs are the oldest known placoderms. Antiarchs are distinguished from other placoderms by having a bipartitite 'cancellous' layer below the outer omament layer of their dermal plates. I proposed recently (Burrow 2005) that the inner layer was formed by cartilage globules encased in perichondral bone, and I suggest here that this layer underlying antiarch dermal plates is homologous with the endoskeletal cartilage layer lining the shields of osteostracan and galeaspid agnathans. The Sinacanthidae from the Early Silurian of China are known only by fin spines, which had cartilage lining their inner surface (Sansom et al 2005). Perhaps the basic separation between plates (including spines) and scales in early vertebrates which had a dermal skeleton was determined by the developmental extent of endoskeletal cartilage. BURROW, C.J., 2005. Histological structure of the cancellous bone layer in Bothriolepis canadensis (Antiarchi, Placodermi). Lethaia 38, 105-110. JANVIER, P., 2001. Ostracoderms and the shaping of the gnathostome characters. In Major Events in Early Vertebrate Evolution, AHLBERG, P.E., ed., Taylor and Francis, London, 172-186. SANSOM, I.J., WANG, N.Z. & SMITH, M., 2005. The histology and affinities of sinacanthid fishes: primitive gnathostomes from the Silurian of China. Zoological Journal of the Linnean Society 144, 379386. RAY-FINS OF THE GOGO: EXCEPTIONAL DEVONIAN FOSSILS SHED LIGHT ON THE EARLY EVOLUTION OF ACTINOPTERYGIAN FISH Brian Choo Department of Earth and Marine Sciences, Australian National University, Canberra, ACT 0200, Australia; Museum Victoria, GPO Box 666, Melbourne, VIC 3001, AustraHa, bchoo-@miiseum.vic.gov.aii Key words: Moythomasia, Gogo Formation, Actinopterygii, fish (previously presented at the 20th Victorian Universities Earth and Environmental Sciences Conference, Monash University, 26 October 2006) Actinopterygians are today the most diverse group of fishes but many details of their early evolution are unclear, particularly with regards to the interrelationships of stem-group taxa. Most early forms are imperfectly known due to limitations of preservation and are usually represented either as flattened skeletons with minimal preservation of delicate internal features, or as disarticulated threedimensionally preserved elements. 54
The famous Late Devonian Gogo fish fauna of Western Australia has produced fossil material with an extraordinary level of preservation within calcareous nodular concretions. Fish are often recovered as entire individual animals with full dermal and perichondral preservation in three-dimensions, including the only Devonian actinopterygians in the world to combine finely preserved neurocranial detail with the remainder of the skull and associated postcrania in articulation. Basal actinopterygians are a common component of the Gogo fauna with at least four taxa present. ''Mimia" toombsi (a preoccupied genus) and Moythomasia durgaringa have featured in most recent phyletic studies of early ray-finned fish. A second species of ''Mimid' and a third, as yet undescribed genus are currently being examined. The July 2005 field expedition recovered a wealth of new material including at least 14 complete or partial actinopterygians. These specimens will allow for a complete description of the new taxa as well as a thorough redescription of "M/mza" and Moythomasia, with preliminary observations suggesting inconsistencies with previously published reconstructions.
A NEW POSSIBLE HALECOMORPH FISH FROM THE MID-CRETACEOUS (ALBIANCENOMANIAN) WINTON FORMATION OF ISISFORD, CENTRAL-WESTERN QUEENSLAND, AUSTRALIA Stephen J. Faggotter\ Steven W. Salisbury^'^ and Yoshitaka Yabumoto^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia; ^Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA; ^Kitakyushu Museum of Natural History and Human History, 2-4-1, Higashida, Yahatahigashiku, Kitakyushu, Fukuoka, 805-0071, Japan Key words: Halecomorphi, Winton Formation, Cretaceous, Queensland In the mid-1990s, an articulated partial skeleton of a large (1-1.5m) fish was collected from the midCretaceous (latest Albian-earliest Cenomanian) Winton Formation of Isisford, central-western Queensland, Australia. The specimen is preserved in a large sandstone nodule that has split into four pieces, and was found in close association with the holotype of the basal eusuchian crocodyliform, Isisfordia duncani. Elements preserved include part of the head (bones anterior to the hyomandibula are missing), pectoral fins, abdominal vertebrae, and ribs.
Although the anterior portion of the head, the caudal part of the body, and the dorsal, anal and pelvic fins are missing, recent studies indicate that this specimen is probably allied to Halecomorphi by the following characters: a pair of extrascapulars covering the posterior margin of the cranium roof, the relatively large posttemporal, the large and wide hyomandibula, and the relatively large subopercle. However, the stout first pectoral fin ray, many supraneurals, and long ribs are not found in, or are rare in, halecomorphs, but these characters are recognized in some basal teleosts (i.e. ichthyodecfiforms, osteoglossiforms, or elopomorphs). Further preparation of the specimen is required before comparisons can be made with other basal Halecostomi and a possible new ichthyodectiform discovered near Isisford in 2005. The specimen possibly represents the first freshwater basal halecomorph from the Winton Formation.
PREPARATION OF THE TYPE MATERIAL OF ISISFORDIA DUNCANI, A BASAL EUSUCHIAN CROCODYLIFORM FROM THE MID-CRETACEOUS (ALBIANCENOMANIAN) WINTON FORMATION OF ISISFORD, CENTRAL-WESTERN QUEENSLAND, AUSTRALIA Kerry Geddes\ Steven W. Salisbury^'^ and Joanne Wilkinson^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia, k. geddesf&uq, edu. au: ^Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA; ^Queensland Museum, 122 Gerler Road, Hendra, QLD 4011, Australia 55
Key words: Fossil preparation, Winton Formation, Cretaceous, Queensland Isisfordia duncani is a new, basal eusuchian crocodyliform from the mid-Cretaceous, (AlbianCenomanian) Winton Formation of Isisford, central-western Queensland. It is Australia's best-preserved and most complete fossil crocodyliform, represented by a near-complete articulated skeleton (the holotype), a complete skull (the paratype), a second partial articulated skeleton and a partial mandible. These specimens were found in nodules of medium-grained volcanoclastic sandstone of fluvial origin. Most had broken into interconnecting blocks that were found in close association. Prior to preparation, typically only small parts of the fossils were visible as bony projections from some edges of the sandstone blocks. Preparation of both the holotype skeleton and the paratype skull was carried out mechanically using a range of pneumatic air-scribes, and for some of the blocks, large amounts of fossil-free matrix were removed using a diamond saw. In light of the material's relevance to the origin of eusuchian crocodyliforms, particular attention was paid to the preparation of areas such as the intervertebral joints on the holotj^e and the secondary choanae on the paratype. Chemical stabilisation of the fossils was kept to a minimum, with sandstone matrix left in place to support delicate areas. In order to emphasize the visual aesthetics of each specimen, the matrix close to the fossil bone was carefully shaped and smoothed off using a pneumatic air-scribe. Additionally, on the holotype, the matrix around the skeleton was smoothed to give a narrow border, beyond which the surrounding matrix was flattened to the same plane as the skeleton, then gouged longitudinally.
NEW OPPORTUNITIES FOR TESTING COMPETING BIOGEOGRAPHIC HYPOTHESES ABOUT THE ORIGINS OF THE AUSTRALASIAN BAT FAUNA Suzanne Hand\ Trevor Worthy^, Michael Archer\ Henk Godthelp\ Robin Beck\ Alan Tennyso^^ Paul Scofield"* and Bernard Sige^ ^School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia, s.hand@unsw.edu,au: ^School of Earth and Environmental Sciences, Adelaide University, Adelaide, SA 5005, AustraUa; ^Museum of New Zealand Te Papa Tongarewa, PC Box 467, Wellington, New Zealand; "^Cantebury Museum, Canterbury Museum, Rolleston Avenue, Christchurch 8013, New Zealand; ^ Paleoenvironnements & Paleobiosphere, UMR-CNRS 5125, Universite Claude Bernard-Lyon 1, Bat. GEODE, 2 rue Dubois, F-69622 Villeurbanne Cedex, France Key words: palaeobiogeography, bats, Australia, New Zealand New bat fossils from Australia (Eocene and Oligo-Miocene), New Zealand (Miocene), South America (Eocene), Africa (Eocene) and India (Eocene) are providing new opportunities for testing competing biogeographic hypotheses concerning the origins of the Australasian bat fauna. The New Zealand Miocene fossils include bats referable to modem bat families as well as bats that appear to have no close living relatives. While yet limited, the fauna has affinities with Eocene (55 Ma) and Ohgo-Miocene (25-12 Ma) Australian faunas, as well as Eurasian and South American bat faunas. Like Australia's Tertiary bats. New Zealand's Miocene bat fauna appears to have been derived from more than one geographic source. The new fossils enable testing of the "out of Asia" versus "out of South America" biogeographic hypotheses (based on analysis of both molecular and morphological data) for several extinct and extant Australasian bat lineages.
DESCRIPTION OF A NEW SPECIMEN OF BARAMEDA DECIPIENS (RHIZODONTIDA) AND HETEROCHRONY IN THE RHIZODONTID PECTORAL FIN Timothy Holland^'^ ^Department of Zoology, La Trobe University, Melbourne, VIC 3086, Australia, tholland@museum.vic.gov.au.; ^Museum Victoria, Melbourne, Victoria 3001, Australia. Key words: Barameda, Mansfield, pectoral fm, heterochrony.
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The description of a new large specimen of Barameda decipiens from the Early Carboniferous (Toumaisian) sediments of Mansfield, Victoria provides new information regarding the ethmosphenoid region of the braincase, branchial series and pectoral fm in rhizodontids. Several differences in morphology, most notably the poorly ossified endochondral bones of the pectoral fins in B. decipiens, has allowed the erection of a new smaller species, B. mitchelli n. sp. Heterochronic processes may account for the poor ossification of the pectoral fin relative to other, wellossified skeletal elements in B. decipiens. The absence of ossified entepicondylar and pectoral processes on the humerus of B. decipiens is comparable with that of juvenile specimens of the rhizodontid Sauripteus and the tristichopterid Eusthenopteron (these processes ossify later during development in tetrapodomorph fish and tetrapds). These observations suggest a difference in developmental timing between the entepicondyle and other elements of the humerus in B. decipiens, a pattern which when extrapolated could occur in other posterior processes of pectoral fin elements, including the postaxial flange on the ulnare. This flange is present in tristichopterids but absent in rhizodontids and elpistostegalids, such as Tiktaalik, which is closely linked with the origin of tetrapods. HOLLAND, T. M., WARREN, A., JOHANSON Z., LONG'J., PARKER K., & GARVEY'J. (in press). A
new species of Barameda (Rhizodontida) and heterochrony in the rhizodontid pectoral fm. Journal of Vertebrate Paleontology. CRANIAL OSTEOLOGY OF MINMI SP., A BASAL ANKYLOSAURID THYREOPHORAN (DINOSAURIA: ORNITHISCHIA) FROM THE EARLY CRETACEOUS (ALBIAN) ALLARU FORMATION OF RICHMOND, NORTH- WESTERN QUEENSLAND, AUSTRALIA Lucy G. Leahey\ Steven W. Salisbury^'^ and Ralph E. Molnar^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia (s4057588@student.uq.edu.au); ^Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA; ^Museum of Northern Arizona, 3101 N. Fort Valley Road, Flagstaff, AZ 86001, USA Key words: Minmi, Ankylosauria, Cretaceous, Queensland Minmi is the only known genus of ankylosaur endemic to Australia. Eight specimens are known from the Early Cretaceous of Queensland, and one from similarly aged sediments in southern Victoria. Only two of these specimens have been described in any detail: the type specimen (QM F10329) of Minmi paravertebra from the Aptian Bungil Formation near Roma, south-western Queensland, and a partial skeleton (QM F18101) assigned to Minmi sp. from the Albian Allaru Formation near Richmond, northwestern Queensland. The latter represents one of the world's most complete Early Cretaceous ankylosaurs, and the best-preserved dinosaur fossil from Australia. The skull of QM F18101 is one of only four ankylosaur skulls known in which the majority of sutures have not been obliterated by extensive osseus ornamentation. A preliminary description of this specimen was provided in 1996. At the time, portions of the skull had not been fully prepared. Further preparation of the skull of QM F18101 has revealed new information on the morphology of the palate and narial region. Recent phylogenetic analyses have shown that nodosaurids and ankylosaurids independently acquired an osseous secondary palate. Linked to the formation of this feature is the development of a complex nasal cavity and/or paranasal sinus system. The extent to which these features are developed in Minmi will provide valuable information on the early evolution of ankylosaurids, as well as some possible physiological attributes of the group.
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LIMITED EFFECT OF THE QUATERNARY'S LARGEST SUPER-ERUPTION (TOBA) ON LAND MAMMALS FROM SOUTHEAST ASIA Julien Louys School of Biological, Earth and Environmental Sciences, University of NSW, Sydney, NSW 2052, Australia Key words: super-eruption, mammals, Toba The effect of the Toba super-eruption at '-74ka on the mammals of Southeast Asia is examined. Although few Late Pleistocene sites from Southeast Asia have been described, an analysis of those which pre-date Toba reveal relatively few species became extinct following the eruption. It is likely that species survived in refugia immediately following the eruption, and that they repopulated vast areas following a short period of environmental devastation. This study highlights the robustness of mammals in coping with catastrophic events, and questions the perceived human monopoly in overcoming ecological adversity.
OSTEOLOGY AND BIOMECHANICS OF THE CRUS AND PES IN RHOETOSAURUS BROWNEI LONGMAN (DINOSAURIA: SAUROPODA) FROM THE MIDDLE JURASSIC INJUNE CREEK GROUP OF ROMA, SOUTH-WESTERN QUEENSLAND Jay P. Nair^ and Steven W. Salisbury^'^ ^School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072, Australia s413822()@student.uq.edu.au; "Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA 15213-4080, USA Key words: Sauropoda, Injune Creek Group, Middle Jurassic, Queensland In the early 1920s, the discovery of exposed vertebrae on Durham Downs Station (now Taloona), near Roma, south-western Queensland, led to the naming of Australia's first non-avian dinosaur, Rhoetosaurus browneU by Heber Longman in 1926. Initially, more than 20 fragmentary vertebrae, mostly consecutive caudals, as well as fragments of the pelvis and a hind limb were collected. The locality was relocated in the mid-late 70s, and an almost complete left pes, more vertebrae, ribs and tibial fragments were unearthed. The material derives from the Injune Creek Group (Middle Jurassic). Despite having been known for over 80 years and being Australia's most complete sauropod, the phylogenetic relationships of Rhoetosaurus have never been determined with any certainty. In the last 20 years, several new Triassic and Early Jurassic sauropods have been described outside Australia. Combined with phylogenetic hypotheses and improved trackway and morphological data, these discoveries have vastly improved our understanding of sauropod evolution and locomotor biomechanics. Key changes in the evolution of sauropod limbs relate to the adoption of a columnar gait from what was essentially a digitigrade precondition. The timing of this transition is poorly constrained outside of Neosauropoda. Although several older and more basal eusauropod pedes are known, few have been described, and in general, the pedal morphology is not known in as much detail as in neosauropods. Analysis of the osteology of the cms and pes of Rhoetosaurus will provide new information on the locomotor evolution of basal sauropods.
KOALA CONUNDRUMS: A NEW SPECIES OF MIDDLE PLEISTOCENE MADAKOALA (PHASCOLARCTIDAE, MARSUPIALIA) HAS IMPLICATIONS FOR FOSSIL VERTEBRATES AS BIOCORRELATIVE TOOLS Gilbert J. Price^ and Scott A. Hocknull^
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^Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis, University of Queensland, St. Lucia, QLD, 4072, Australia, g,price 1 (amq.edu.au: ^Geosciences, Queensland Museum, 122 Gerler Road, Hendra, Queensland, Australia, 4011.Key words: Madakoala, biocorrelation, extinction. Pleistocene The utility of fossil vertebrates as biochronological indicators of Australian fossil deposits is governed by accurate physical dating of important local faunas, and the completeness (or incompleteness) of the fossil record. Recent systematic excavations in caves at Mt. Etna, central eastern Queensland, coupled with an intensive U-series dating study, has revealed a remarkable new middle Pleistocene faunal assemblage. Amongst the new assemblage, dominated by rainforest taxa (e.g., Dactylopsila, Strigocusus), we have identified an undescribed species of koala, Madakoala sp. nov. Madakoala sp. nov is similar in size to other members of the genus, but differs in a number of morphological characters of the M^ and M^ (e.g., relative position of stylar cusps, length and width of cingula). The only other members of the genus, M devisi and M. wellsi, are known only from supposed middle Miocene localities of central Australia. Placement of such taxa in middle Miocene deposits was based on morphological stage-of-evolution techniques and stratigraphic correlation. However, identification of Madakoala in chronologically wellconstrained middle Pleistocene deposits raises serious questions over the value of some fossil vertebrates, such as Madakoala, as biochronological markers. Better physical dating and stratigraphic control in regards to collecting methodologies, and re-evaluation of stage-of-evolution biochronological methods, is critical to establish the usefulness of fossil vertebrates as biochronological tools. Regardless, extinction of Madakoala in the middle Pleistocene represents another long-lived lineage of rainforest marsupials that succumbed to significant habitat reorganisation as a direct result of the long-term drying-out of Australia.
BIG BIRD AND CHICKEN LITTLE: THE EGG OF GENYORNIS NEWTONI Natalie Schroeder^ and Nigel Spooner^ ^ South AustraHan Museum, North Terrace, Adelaide 5000; University of Adelaide, North Tcrrace, Adelaide, SA 5000; ^DSTO, Edinburgh SA, 5111; formerly Research School of Earth Scicnces, ANU, Canberra, ACT, 2600 Key words: Genyornis; egg; reconstruction; morphology Fragments of a near-complete egg of Genyornis newtoni have been reassembled in three dimensions. For the first time, the form and dimensions of an egg can be directly observed. A visual comparison of eggs of other large birds and their pelvises is given. Egg size does not always correlate well with body size (eg. kiwis); this egg suggests that Genyornis eggs - and, therefore, Genyornis hatchlings -.were unusually small for such a large bird.
PALYNOLOGY OF THE INVERLOCH FOSSIL SITE, GIPPSLAND BASIN, AUSTRALIA Doris Seegets-Villiers Monash University, Melbourne; School of Geosciences, Monash University, PC Box 28E,VIC 3800, Australia; doris.seegets~viIlicrs@sci.monash.edu.ai] Key words: Early Cretaceous, Palynology, Gippsland Basin The Inverloch fossil site is renowned for its Early Cretaceous vertebrate assemblage preserved within an ancient river system. Intriguingly the site had a diverse faunal biota living at a position well within the Antarctic Circle. A MAAT (Mean annual air temperature) of between -T" C and raises the question of the survival of floral and faunal elements. The possible adaptation of the fossil vertebrates to cool temperatures is well documented. However, the floral assemblage of the site has until now not been fully established. Samples were taken and investigated for their palynological content. It was found that ferns by far dominate the assemblage. The next most important spore-pollen groups are the lycopods and 59
gymnosperms that occur at roughly equivalent percentages. Mosses might have been expected to play a more dominate role in this fluvial environment but are overall only represented in small numbers along with the hepatics that are the least prolific floral element. The major species amongst the ferns are Cyacthidites minor, C. australis and Baculatisporites comaumensis. Gymnosperms are mainly represented by Cycadopites nitidus, Araucariacites australis and the species Alisporites. The major lycopod group is the genus Retitriletes. A JUVENILE SKULL OF SARCOPHILUSLANIARIUS Clara Stefen^ and Michael Morlo^ ^Staatliche Naturhistorische Sammlungen Dresden, Museum flir Tierkunde, Konigsbrucker Landstrasse 159, 01109 Dresden, Germany, cmstefen@web.de; ^Forschungsinstitut Senckenberg, Senckenberganlage 25, 60325 Frankfurt, Germany Key words: juvenile skull, unclear provenience A juvenile skull of Sarcophilus laniarius from Austraha or Tasmania is briefly described and compared to recent specimens. The dentition indicates that it is still a juvenile, as m3 has not yet reached occlusal height and the canines are still erupting to their full length. The erupted molars Ml, M2 and ml are hardly wom. Compared to recent Sarcophilus laniarius the teeth, especially the incisors and premolars, appear more robust and are slightly larger. The incisors as well as the molars are slightly higher in the fossil specimen. In ml and m2 the protoconid is higher relative to the talonid in the fossil species. Sarcophilus moornaensis is smaller than Sarcophilus laniarius (CRABB 1982:511), so that the studied skull cannot be attributed to S. moornaensis as the teeth are of similar size to slightly larger than in Sarcophilus laniarius. Therefore, the specimen is attributed to S. laniarius despite subtle differences especially in robustness. The specimen SMF M8274 was bought at the Munich fossil fair by the Forschungsinstitut und Naturmuseum Senckenberg Frankfurt, Germany. The provenience of the specimen is unclear, because it was sold as "Ischyrictis'\ a hypercamivorous mustelid, from MN 3 of Wintershof-West, a lower Miocene locality in Southern Germany. An important aspect of this presentation thus is 1) to get more information on its provenience and 2) to rule out that it is a stolen specimen. CRABB, P., 1982. Pleistocene dasyurids from southwestern New South Wales. In: Carnivorous Marsupials, Vol 2, M. Archer, ed.. Royal Zoological Society of New South Wales, Chipping Norton, 511516. PRELIMINARY RESULTS OF TOOTH MICROWEAR BETWEEN SOME MARSUPIAL AND PLACENTAL CARNIVORES Clara Stefen Staatliche Naturhistorische Sammlungen Dresden, Museum fiir Tierkunde, Konigsbrucker Landstrasse 159, 01109 Dresden, Germany, cmstefen@web.de Key words: tooth microwear, carnivores The study of microwear patterns of teeth has become an important tool for paleontologists to reconstruct the diet and chewing behavior of fossil taxa. Initial studies focused on herbivoros animals such as primates and herbivores, but included some marsupials, carnivores and - mainly more recently - insectivores and rodents as well. In order to infer the diets of fossil taxa the microwear structure of recent mammals has to be understood properly and the relation to food properties and to enamel structure should be considered. The study of microwear could also reveal differences in chewing behavior between taxa. In this respect teeth of Thylacinus and Sarcophilus have been surveyed (Robson & Young 1990). This aspect of 60
microwear study will be addressed further with this analysis of which preliminary results will be presented. As significant differences between the tooth enamel structure and particularly the schmelzmuster between some placental and marsupial carnivores can be observed (Koeningswald 1994; Stefen 1997), the question addressed herein is whether microwear features indicate differences in the chewing mode and occlusal pattern between these groups. The marsupials Thylacinus cynocephalus and Sarcophilus laniarius and the placentals Canis lupus, Gulo gulo and Vulpes vulpes are chosen as examples. KOENIGSWALD, W.von., 1994. Differenzierungen im Zahnschmelz der Marsupialia im Vergleich zu den Verhaltnissen bei den Placentalia (Mammalia). Berliner geowissenschaftliche Abhandlungen E13, 4581. ROBSON, S.K. & YOUNG, W.G., 1990. A comparison of tooth microwear between an extinct marsupial predator, the Tasmanian Tiger Thylacinus cynocephalus (Thylacinidae) and an Extant scavenger, the Tasmanian Devil Sarcophilus harrisii (Dasyuridae: Marsupialia). Australian Journal of Zoology 37, 575589. STEFEN, C., 1997. Tooth enamel structure of some Australian carnivorous marsupials. Alcheringa 23, 111-132.
FUNCTIONAL MORPHOLOGY OF PLEISTOCENE TREE-KANGAROOS {BOHRA) FROM THE NULLARBOR PLAIN Natalie M. Warburton^ ^ Gavin J. Prideaux^'^ and Kathryn Harvey^ ^ Western Australian Museum, Locked Bag 49, Welshpool DC 6986, WA, Australia, nwarbo@graduate.uwa.edu.au; ^ The University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia; ^ Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia Key words: Macropodidae, postcranial skeleton, arboreal, ecomorphology Species in the extinct genus Bohra have been allied with living tree-kangaroos (Dendrolagus) on the basis of marked similarities in isolated craniodental and hind limb elements. The first relatively complete skeletons of Bohra have been recovered from middle Pleistocene assemblages preserved in caves beneath the Nullarbor Plain of south-central Australia. Here we provide a brief summary of our work to date. Craniodental data confirm that Bohra is closely related to, but more plesiomorphic than the extant genus Dendrolagus, and that traits shared by Bohra and Petrogale (rock-wallabies) confirm molecular phylogenies suggesting that tree-kangaroos and rock-wallabies share a common ancestry. Overall patterns of postcranial functional morphology from the axial skeleton, forelimb and manus, and hind limb and pes support the hypothesis that Bohra was arboreal. The presence of Pleistocene species on the Nullarbor Plain indicates that tree-kangaroos had far broader geographic and climatic ranges than hitherto anticipated, and also demonstrates that the 'Treeless' Plain was not always treeless.
Posters: Marine Mammals in Deep Time: Diversity, Distribution and Evolution ARAEODELPHISNATATOR KELLOGG, 1957, THE MOST PRIMITIVE KNOWN MEMBER OF THE PLATANISTIDAE (ODONTOCETI, CETACEA) AND A REVIEW OF PLATANISTIDAE FROM CALVERT CLIFFS (MIOCENE, CHESAPEAKE GROUP), MARYLAND, USA David J. Bohaska\ Lawrence G. Barnes^ and Stephen J. Godfrey^ ^National Museum of Natural History, Paleobiology, PC Box 37012, MRC-121, Washington D.C. 200137012, USA; ^Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Blvd, Los Angeles, CA 90007, USA; ^Department of Paleontology, Calvert Marine Museum, P.O. Box 97, Solomons, MD 20688, USA, Godfresi@coxaLmd.us Key words: Platanistidae, Araeodelphis, Zarhachis, Pomatodelphis 61
The extant river dolphins Platanista minor and P. gangetica (Platanistidae), are amongst the most highly derived odontocetes. Stem-ward Miocene platanistids are more diverse anatomically and are marine in habitus. A partial cranium (USNM 526604) from the Plum Point Member (Bed 7, Calvert Formation, Early Miocene, Burdigalian) Calvert Cliffs, Maryland, is identified as Araeodelphis natator Kellogg, 1957. Previously, this species was un-assignable to any odontocete family for lack of diagnostic cranial remains, but USNM 526604 demonstrates that A. natator is a platanistid and is its most primitive known member. In addition to Araeodelphis, Miocene Platanistidae from Calvert Cliffs comprises at least three other genera. Zarhachis is presently known from Bed 4 through Bed 14 of the Calvert Formation. In Zarhachis jflagellator, the pterygoid air sac sinus invades the medial face of the robust and enlarged supraorbital crest and the nasals and frontals are swollen to form a hemispherical cranial vertex, a condition not seen in Pomatodelphis. The most common platanistid from Calvert Cliffs is Pomatodelphis sp., characterized by the presence of a stout horn-like prong anteriorly on the frontal moiety of the supraorbital process. Pomatodelphis sp. is known from Bed 12 of the Calvert Formation through to Bed 17 of the Choptank Formation. The third platanistid is undescribed and derives from the Little Cove Point Member (Beds 22 and 23) of the St. Marys Formation. It is known from two partial crania, neither of which preserve the supraorbital crests.
PATHOLOGICAL DOLPHIN ROSTRA FROM CALVERT CLIFFS (MIOCENE, CHESAPEAKE GROUP), MARYLAND, USA Jennifer M. Gerholdt and Stephen J. Godfrey Department of Paleontology, Calvert Marine Museum, P.O. Box 97, Solomons, MD 20688, USA, God fL'e si . cal. met .u s Key words: Pontoporiidae, periostitis, Miocene, Calvert Cliffs Five fossilized dolphin partial rostra from Calvert Cliffs, Maryland (Miocene, Chesapeake Group), exhibit periostitis, the first such pathology reported from Calvert Cliffs. Periostitis is an inflammation of the periosteum secondary to a predisposing event such as a fracture or trauma. CT scans reveal that the periostitis in these rostra is limited to the premaxillae. Presumably, the pathology was the result of an infection or injury, such as an abrasion wound or a fracture only to the very gracile premaxillae. In most specimens, the bones became progressively swollen and gnarled over the course of months and/or years as evidenced by the onion-like layering within the pathology. There are also varying degrees of healing exhibited in these specimens. These pathologies seem not to have been life threatening despite the gross size and shape of most of these periosteal reactions. Ironically, these pathologies seem to have contributed to the preservation of members of a species that is otherwise unknown because the non-pathological morphology of these rostra is unHke any other odontocete from Calvert Cliffs. CMM-V-2663 is the only specimen preserving maxillary alveoli and teeth. The bilateral proximity of the maxillary tooth rows, the size and spacing of the alveoli, and the hatchet shaped root of the teeth are similar to those seen in the extant La Plata dolphin, Pontoporia blainvillei, which suggests that this unnamed Miocene dolphin was a member of the Pontoporiidae.
A NEW GENUS AND SPECIES OF LATE MIOCENE PONTOPORIID DOLPHIN (ODONTOCETI, CETACEA) FROM THE ST. MARYS FORMATION (CHESAPEAKE GROUP), MARYLAND, USA Stephen J. Godfrey^ and Lawrence G. Barnes^ ^Department of Paleontology, Calvert Marine Museum, P.O. Box 97, Solomons, MD 20688, USA, GodiTesj@coxalmd.us; ^Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Blvd, Los Angeles, CA 90007, USA
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Key words: Pontoporiidae, Fossil, Miocene, Calvert Cliffs A new genus and species of extinct dolphin in the odontocete family Pontoporiidae is based on a partial cranium of Late Miocene age, circa 9 to 10 milHon years old, from the Little Cove Point Member of the St. Marys Formation in Maryland, USA. Pontoporiidae are amongst the smallest of cetaceans, and this dolphin is the smallest known pontoporiid, being probably less than 1.5 meters in total body length. It is also geochronologically the second oldest named pontoporiid in the world. This new pontoporiid shares with late Middle Miocene Brachydelphis mazeasi from the eastern South Pacific and the latest Miocene and Phocene species of Parapontoporia from the North Pacific left-skew asymmetry of the cranial vertex. Thus, all of the earliest known Pontoporiidae have cranial asymmetry, in contrast to the Pliocene fossil pontoporiids, Pontistes rectifrons and Pliopontos littoralis, and the Recent Franciscana, Pontoporia blainvillei, all of which have symmetrical crania. This suggests that cranial asymmetry may be the primitive character state among stem Pontoporiidae. Apomorphies of this new species based solely on a partial cranium, CMM-V-2234, include small size, thick cranial bones, wide premaxillary sac fossae, a medial projection of each maxilla onto the lateral side of each nasal, and the highest part of the cranial vertex being formed by the nasals rather than the frontals.
DEAD WHALES AS HABITATS: INVERTEBRATE COMMUNITIES AND THEIR EVOLUTIONARY IMPLICATIONS Steffen Kiel^ and James L. Goedert^ ^ Earth Sciences, University of Leeds, UK; Department of Paleobiology, Smithsonian Museum of Natural History, Washington, DC 20013, USA, steffen.kiel@gmx.de; ^Burke Museum, University of Washington, Seattle, Washington, USA Key words: whales, deep-sea, chemosynthesis, fossil record Sunken dead whales (whale-fall) are rich, localized food-sources on the otherwise nutrient-poor deep-sea floor. Invertebrate communities that colonize whale skeletons resemble in their taxonomic compositions those found at hydrothermal vents and methane seeps. The bivalves, snails, and tube worms are taxa that rely on chemotrophic endosymbiotic bacteria sustained by sulfide and methane derived from the anaerobic breakdown of oil in whale bones. This source and pathway of nutrients has been available since Eocene time, and it has been suggested that dead whales provided dispersal "stepping stones" for invertebrates that inhabit vents and seeps (Smith & Baco 2003). The fossil record, however, tells a different story. Whereas Miocene and modem whale-fall communities are very similar. Eocene and Oligocene examples lack vent and seep-type taxa that most strongly rely on sulfide from the breakdown of bone-oil (Kiel & Goedert 2006). Two possible reasons for this marked difference are: Eocene and Oligocene whales were too small to have enough oil in their bones to sustain these animals, or the relative oil content of whale bones rose significantly in the Miocene. Thin-section work on Oligocene whale bones from Washington State, USA, reveals that marrow spaces in cancellous bones of three specimens contained large amounts of fecal pellets, something not observed in Miocene examples. This opens the possibility that different taphonomic processes were operating in the Oligocene and Miocene. KIEL, S. & GOEDERT, J.L., 2006. Deep-sea food bonanzas: Early Cenozoic whale-fall communities resemble wood-fall rather than seep communities. Proceedings of the Royal Society B 273, 2625-2631. SMITH, C.R. & BACO, A.R., 2003. Ecology of whale falls at the deep-sea floor. Oceanography and Marine Biology: an Annual Review 41,311-354.
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