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The Taiwan Mollusks The Rissoacea (Mol1usca:Mesogastropoda) from Lutao, Taitung

Chen-Kwoh Chang and Wen-Lung Wu

Research Center for Biodiversity Academia Sinica


The Taiwan Mollusks The Rissoacea (Mo11usca:Mesogastropoda) from Lutao, Taitung

Chen-Kwoh changl and Wen-Lung wu2 1.1373, Phelps Av., #8, San Jose, CA 95 117, USA 2.Research Center for Biodiversity, Academia Sinica, Taipei, TAIWAN Microscopy photos by Wen-Lung Wu, Ph. D. (Manchester, UK) Research Fellow and Professor of Zoology Research Center for Biodiversity, Academia Sinica Taipei 115-29, TAIWAN Telephone : 02-27899547 02-27899553 Fax : 02-27899547 E-mail : malacolg@gate.sinica.edu.tw Web-site : http://shell.sinica.edu.tw http://shellmuseum.sinica.edu.tw

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Copyright 2004 by Research Center for Biodiversity, Academia Sinica 128, Yen-Chiu-Yen Road Sec.2, Nankang, Taipei 115-29, TAIWAN

Editorial Office Laboratory of Malacology Research Center for Biodiversity, Academia Sinica Taipei 115-29, TAIWAN On the Cover : Shell Painting with rissoids from Lutao (Mr. R. J. Yeh) by Wen-Shou Chang and Wen-Lung Wu ISBN : 957-0 1-9592-4 First published 2004 U.S. $20.00


The Taiwan Mollusks The Rissoacea (Mo11usca:Mesogastropoda) from Lutao, Taitung Chen-Kwoh changl and Wen-Lung w u 2 1. 1373 Phelps Av., #8, San Jose, CA 95 117, USA 2. Research Center for Biodiversity, Academia Sinica, Taipei 11529, Taiwan

Chen-Kwoh Chang and Wen-Lung Wu (2004) The Taiwan Mollusks : The Rissoacea (Mo11usca:Mesogastropoda) from Lutao, Taitung. One hundred and thirty-two species of Superfamily Rissoacea from Lutao (the Green Island), Taitung are reported with diagnosis, distribution, dimension and microscopy colored pictures etc. There are eight families such as Family Rissoidae, Iravadiidae, Barleeidae, Stenothyridae, Assimineidae, Truncatellidae, Adeorbidae and Dialidae are belonging to the Rissoacea were found from Lutao, Taiwan. Ten new species are described in this monograph and namely, Microstelma formosus, Microstelma lutaoi, Pandalosia lutaoi, Pandalosia moerchiella, Rissoina taiwanica, Rissoina thatcheria, Rissoina lutaoi, Rissolina humpa, Rissolina ovalis and Rissolina laseroni. Eight species, unidentified are also described. Most of them are probably new species but needing more information. Key to 8 families of Rissoacea from Lutao and keys to species of genera having 4 species or more are also provided. Keywords: Gastropoda, Mesogastropoda, Rissoacea, sp. nov., Lutao (the Green Island), Taiwan.


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Introduction Lutao (the Green Island) is a small island, southeastern Taiwan. There are abundant micromollusks, about 1,300 species on the beach around this island been identified by the authors. One hundred species of Rissoidae and 32 species of other families (Superfamily Rissoacea) are reported in this monograph. Rissoidae is one of the largest families, only second to Family Turridae (Mangeliidae and Clavidae included) been found in Lutao, Taiwan. All species of this Superfamily are miniature to small, shaped from depressed to cylindrical but their aperture are ovate, circular or semicircular with a rounded anterior end. Radula is typical taenioglossate. Most species are marine and some are fresh water or terrestrial form.

Materials and Methods All the specimens are collected from the beach of Lutao by Mr. T.Y. Lin, a teacher of the primary school on the island. He collected by hand sorting throughout the beaches around the island in different seasons for many years. All specimens illustrated have been present to the Malacology Lab., Research Center for Biodiversity, Academia Sinica, Taiwan. Beach shells always lose their soft bodies and operculum. Hence, shell characters are used mainly for classification in this monograph. The microstructure of each shell is observed and imaged by using the Zeiss-Stemi microscope. The number of axials and spirals is usually counted on the penultimate whorl instead of body whorl for less variation. Dimension size is measured in shell length and shell width in mm. Article describing microshells without pictures equals to nothing. No body knows that the author's identification is right or wrong. Hence, this monograph uses slides, magnifying about 5X in original color in two or three views for each shell. Identification is the most difficult job when working on thousands shells, especially the micromollusks. It could be said that no one is error-free. Many errors on the past articles, monographs or shell books by the famous conchologists are found very often. Most errors came from using synonymy. It is very important to point out these errors because those literatures are usually used as guides for identification by all shell workers, conchologists or malacologists. For easier checking the identification, column "Reference for Identification" is added for each species. The name of the reference and its publisher for identification are expressed as "author, year" and the page number or figure number are followed, for example: Tate and May (1901), pl. XXIV-18. For micromollusks, it is easier to find some shells, not described in the past references. Here, we give new names only for those of two or more specimens on hand. Otherwise, we only put them as species, unidentified which probably be new species but needing further information.


Key to the eight families of Rissoacea and keys to species of genera Microstelma, Schwartziella, Pandalosia, Rissoina, Rissolina, Phosinella, Zebinella, Zebina, Moerchiella, Stosicia, Assimineidae, Truncatellidae and Dialidae are also provided.

Classification Superfamily Rissoacea belongs to Order Mesogastropoda (Mollusca: Gastropoda). There are eight families of Rissoacea found from Lutao, namely Rissoidae, Iravadiidae, Barleeidae, Stenothyridae, Assimineidae, Truncatellidae, Adeorbidae and Dialidae. The diagnosis, operculum, radulae and soft bodies of each family are described as below according to Thiele (1 929 - 1935), Habe (1942), Ponder (1 984), Keen (197 l), Brandt (1 974), and Kay (1979) etc. The key to eight Families of Rissoacea from Lutao, Taiwan is provided as follows:

Key to the 8 Families of Rissoacea from Lutao, Taiwan 1

2 3 4

5

6 7

. . Shell, ovate conic or cylindrical ..................................................................................................... 2 Shell, depressed or with low spire ................................................................................... Adeobidae Shell, ovate biconic with apex ......................................................................................................... 3 Shell, cylindrical with apex, truncated ..................................................................... Truncatellidae Peristoma, thin and incomplete ........................................................................................................ 4 Peristoma, thickened or entire .................................................................................................... 5 Shell, amphibious and operculum, paucispiral without peg or ridge ........................... Assimineidae Shell, marine, subtidal without operculum .......................................................................... Dialidae Body whorl, bossed at the left or / and compressed dorsal-ventrally; operculum with a semicircular ridge .......................................................................... Stenothyridae 6 Body whorl, normal .................................................................................................................. Inner wall with chitinous layer, shell, smooth, red-brown with operculum, pegged ....... Barleeidae Inner wall without chitinous layer ................................................................................................... 7 Shell with periostracum, operculum ridged .................................................................... Iravadiidae Shell without periostracum; operculum, pegged or simple .............................................. Rissoidae

Family Rissoidae ( %@!&!%fq ) Rissoidae shells are minute to small, mostly within 8 mm; white, occasionally colored; oval-conic with the spire being higher than the aperture; variously sculptured; aperture, circular, ovate or semicircular with rounded anterior end. Operculum, horny, pegged from its inside nucleus or simple. Animal with head, shortly snouted and eyes situated at the base of the cephalic tentacles, feeding on diatoms and algae filaments. The sexes are separate. Radula is of taenioglossate. Most members are marine, intertidal to 50 meters. Rissoidae was recognized as two main families by early European conchologists: Family Rissoidae and Family Rissoinidae. The former has simple, thin operculum and its aperture is circular or ovate while the latter has an operculum, pegged from its nucleus on its


inside and its aperture is semicircular. It was found to be quite inadequate for the nonEuropean species when their anatomy and life history becomes known. Thiele (1929 - 1935) used Family Rissoidae only for all. Kay (1979) and Ponder (1984) followed, grouping them into two parts. One has distinct anterior canal and the other does not have. As a matter of fact, it is more practical to use shell characters to classify these microshells because beach shells always lose their animal and operculum. Before the early 2oth century, conchologists retained a few genera in the widest sense and split the genera into numerous subgenera which were split again into sections. Such kind of classification makes the classification very confusing. A genus is not a nature unit but a term of convenience to link a number of related species together (Laseron, 1956). In order to simplify the classification, this article eliminates the levels of subgenera and sections using the genera level only for them. The features of the genera occurred at Lutao are described as below after Thiele (1935), Laseron (1956), Keen (1971), Kay (1978) and Ponder (1984). The type species of the above genera are also shown as the following pictures.

Description 15 Genera of Rissoidae from Lutao, Taiwan Genus Rissoa Desmarest, 1814 Type species: Rissoa ventricosa (Desmarest, 1814) Synonymy: Losostoma Bivona, 1838 Diagnosis: Shell, oval conic, straight sided with protoconch, conical of 1-3 whorls, nearly smooth. Sculpture of ribs, occasionally with weak spirals. Aperture, ovate and outer lip thin. Operculum without process. Genus Alvania Risso, 1826 Type species: Alvania cimax (Linne, 1758) Diagnosis: Shell, oval-conic with protoconch, paucispiral, dotted. Cancellate sculpture with spirals only at bottom. Aperture, ovate; outer lip, thin with dentition inside. Operculum without process. Genus Onoba H. et A. Adams, 1852 Type species: Onoba semicostata (Montagu, 1803) Diagnosis: Shell, oval-conic with apex pointed; the subsequent whorls moderately bulging. Sculptured with spirals and faint axial riblets. Aperture, ovate angled above, outer lip, thin. Operculum without process. Genus Merelina Iredale, 1915 Type species: Merelina cheilostoma (Tension-Wood, 1877) Diagnosis: Shell, oval-conic with protoconch, paucispiral, gemmately spiraled. The subsequent whorls, strongly sculptured, latticed, ribbed, or keeled. Aperture, roundish or ovate with continuous duplicate peristoma. Operculum without process. Genus Microstelma A. Adams, 1863 Type species: Microstelma daedala A. Adams, 1 863


Diagnosis: Shell, oval-conic with protoconch, conic, up to 3+ whorls; subsequent whorls, deeply sutured. Sculpture of ribs and spiral straie with domination of spirals at the bottom. Aperture, ovate, produced below; outer lip, thin or weakly variced. Operculum and animal unknown. But Ponder (1984) and Vaught (1 989) put it under this family. Genus Schwartziella Nevill, 1881 Type species: Schwartziella triticea (Pease, 1862) Diagnosis: Shell, elongate or oval-conic, strongly ribbed from suture to suture or to the base over anterior end, columella, parietal wall to the slot at the end of the suture. Operculum simple without peg. Genus Pandalosia Laseron, 1956 Type species: Pandalosia excelsis Laseron, 1956 Diagnosis: Similar to Genus Schwartziella but the varix of the aperture, not entirely with opening at parietal wall. Some authors put it under Schwartziella as subgenus. Genus Rissoina Orbigny, 1840 Type species: Rissoina inca Orbigny, 1840 Diagnosis: Shell, elongate oval-conic; whorls strongly ribbed with or without spiral striae. Aperture semicircular with an anterior canal; outer lip, variced or thickened. Operculum, pegged from nucleus on its inside. Genus Rissolina Gould, 1861 Type species: Rissolina plicatula (Gould, 1861) Synonymy: Costalynia Laseron, 1956 Diagnosis: Rissolina with a strong basal spiral fold below a basal furrow. Laseron (1956) grouped Rissolina shells with a hump at end near the aperture as genus Costalynia. Genus Phosinella Moerch, 1876 Type species: Phosinellapulchra (C. B. Adams, 1850) Diagnosis: Shell having strong reticulate sculpture with axials and spirals of nearly equal strength. Genus Apataxia Laseron, 1956 Type species: Apataxia erecta Laseron, 1956 Diagnosis: Shell with spiral grooves instead of spiral cords; aperture, small. Some authors put it under Phosinella as subgenus. Genus Zebinella Moerch, 1876 Type species: Zebinella decussata (Montagu, 1803) Diagnosis: Shell similar to Rissoina but sculptured of fine axials and spiral striae or cancellate microscopically. Genus Zebina H. et A. Adams, 1854 Type species: Zebina tridentata (Michaud, 1830)


Diagnosis: Shell, oval-conic, smooth, glossy, some with obscurely visible ribs on earlier whorls or microscopically spiral striae at bottom. Aperture, semicircular to ovate with outer lip, thickened. But operculum is simple, not pegged inside. Genus Moerchiella Nevill, 1885 Type species: Moerchiella gigantea (Deshayes, 1863) Diagnosis: Shell similar to Zebina but ribbed on earlier whorls. Some authors put it under Zebina as subgenus. Genus Stosicia Brusina, 1870 Type species: Stosicia mirabilis (Dunker in Weinkauff, 188 1) Synonymy: Isseliella WeinKauff, 1881;Isselia Semper in Schmeltz, 1874 Diagnosis: Shell, oval-conic with cancellate sculpture. Aperture, semicircular to ovate; outer lip variced and fimbriated. Anterior canal, deep cut, visible from bottom as the Planaxis shells. Operculum, not pegged inside but pointed with a terminal nucleus. This group of shells is closer to the Family Planaxis but it is put under Rissoidae traditionally.

Key to 15 Genera of Rissoidae from Lutao, Taiwan Shell without distinct anterior canal in aperture .............................................................................. 2 Shell with distinct anterior canal in aperture ...................................................................................5 Aperture, with single peristoma .......................................................................................................3 Aperture with continuous duplicate peristoma ...................................................................Merelina Sculpture of spirals or ribs dominant ............................................................................................... 4 Sculpture of ribs and spiral cords; protoconch, dotted ..........................................................Alvania Sculpture of ribs dominant ...................................................................................................... Rissoa Sculpture of spirals dominant .................................................................................................Onoba Anterior canal, not visible from bottom ..........................................................................................6 Anterior canal, visible from bottom ....................................................................................... Stosicia Aperture variced over columella; ribbed to the base without spiral striae ...................................... 7 Aperture with outer lip, variced only ............................................................................................... 8 Aperture variced entirely ............................................................................................. Schwartziella Aperture variced, open at parietal wall ............................................................................ Pandalosia Anterior canal, not produced ........................................................................................................... 9 Anterior canal, produced ............................................................................................... Microstelma Operculum, simple ......................................................................................................................... 10 Operculum with peg ..................................................................................................................... 11 Shell, smooth, glossy .............................................................................................................. Zebina Shell, smooth but ribbed at earlier whorls ...................................................................... Moerchiella Sculpture of axials and spirals ....................................................................................................... 12 Sculpture of strong axial ribs ......................................................................................................... 14 Sculpture of strong cancellate........................................................................................................13 Sculpture of microscopic cancellate or fine axials dominant .............................................Zebinella Sculpture of ribs and spiral cord of nearly equal strength ................................................Phosinella Sculpture of ribs and spiral grooves; aperture, smaller .......................................................Apataxia Shell with basal fold ........................................................................................................ Rissolina Shell without basal fold .......................................................................................................Rissoina


Stosicia n~irabilis(Dunker) 4.5 mm, (Ponder, 1984)

Microsteln~adaedala A. Adams 5.4 mm, (Kuroda, 1952)

Rissoa ventricosa (Deserest) 7.6 mm, (Ponder, 1984)

Alvania cimax (Linne) 4 mm, (Ponder, 1984)

Onoba sen~icostata(Montagu) 2 mm, (Ponder, 1984)

Merelina cheilostoma Tension-Wood 3 mm, (Ponder, 1984)

Genus Rissoa Desmarest, 1814 1. Rissoa demessa Tate et May, 1901 (Fig. 1) Synonymy: Haurakia demessa Tate et May, 1901 in May (192 1) Diagnosis: Shell, minute, pale white, oval-conic with apex, decollate. Mature whorls, 34, slightly convex and suture, impressed. Sculpture of rounded ribs with weaker spirals between ribs, fading at bottom; 12 ribs and 6 spirals on the penultimate whorl. Aperture, narrowly ovate and outer lip, simple. Distribution: Off Thoain Bay in Tasmania is the fatherland. It is also found as beach drift at Lutao, Taiwan. Dimension: 2.0x1.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Tate and May (1901), pl. XXIV-18; May (1921), pl. XXIII- 1. Inventory: MLS -RI00001


2. Rissoa discrepans Tate et May, 1901 (Fig. 2) Synonymy: Haurakia discrepans Tate et May, 1901 in May (192 1) Diagnosis: Shell, small, white, oval biconic with protoconch, paucispiral of 2 smooth whorls. Mature whorl, 4, slightly convex. Raised ribs overhanging; suture pit-like; no ribs reaching bottom; 11 ribs on the penultimate whorl; interspace, deep and broad with scarcely spiral straie. Aperture, ovate and outer lip, simple. Distribution: At 80-800 meters depth off Thoain Bay, Tasmania. It is also found off Lutao, Taiwan. Dimension: 3.8 x 2.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Tate and May (1901), pl. XXVI-65; May (1921), pl. XXX-2. Inventory: MLS -RI00002 3. Rissoa pellucida (Powell, 1937) (Fig. 3) Synonymy: Rissoa (Haurakia) pellucida (Powell, 1937) in Powell (1976) Pusillina (Haurakia) pellucida (Powell, 1937) in Ponder (1984) Diagnosis: Shell, minute, subtranluscent, fragile, oval-conic with apex, blunt. Mature whorls, 3-4 with body whorl, large, inflated; sutures, impressed. A few ribs, narrow, short on the body whorl; color, pale white but reddish brown at bottom. Distribution: At 92 meters depth of Three Kings Islands, New Zealand is the fatherland. It is also found as beach drift at Lutao, Taiwan. Dimension: 1.4 x 1.1 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Powell (1976), pl. 41-5; Ponder (1984), p. 131. Inventory: MLS -RI00003 4. Rissoa gradata (Orbigny in Tryon, 1887) (Fig. 4) Synonymy: Rissoina sp. B in Chang (1998) Diagnosis: Shell, small, yellowish, oval, subturreted with apex, flatly domed. Mature whorls, 3-4, flat with a large body whorl and suture, impressed. Ribs, strong, oblique from top left to right with numerous spiral straie between ribs; 10 ribs on the penultimate whorl. Aperture, small, ovate; anterior canal, broad, shallow; outer lip with an axial rib just behind it. Distribution: Jamaica, Caribbean Sea is the fatherland but it is found on the beach of Lutao, Taiwan. Dimension: 3.2 x 1.6 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Tryon (1887), p. 378 and pl. 68-84. Inventory: MLS -RI00004 5. Alvania isolata (Laseron, 1956) (Fig. 5) Synonymy: Haurakia isolate Laseron, 1956 in Laseron (1956)


Alvania (Alvania) isolate (Laseron, 1956) in Ponder (1998) Diagnosis: Shell, minute, oval conic with protoconch, paucispiral, microdotted. Mature whorls, 4, convex and suture, channelled and beaded. Reticulate sculpture with spirals, dominant at bottom; 4-5 spirals and 15-16 axials on the penultimate whorl. Aperture, rounded, somewhat, angled above. Color, yellow with some golden orange spots on shoulder. Distribution: In algae on corals or beach drift from Christmas Island, Cocos Keeling Id., Indian Ocean; Marshall Islands and Hawaii. It is also found as beach drift at Lutao, Taiwan. Dimension: 2.0 x 1.1 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 144; Maes (1967), pl. 5E: Ponder (1984), p. 142. Inventory: MLS -RI00005

6 . Alvania gradatoides (Finlay, 1927) (Fig. 6) Synonymy: Alvania (Linemera) interrupts gratatoides (Finlay, 1927) in Ponder (1984) Diagnosis: Shell, minute, oval-conic with protoconch, paucispiral, convex. Mature whorls, 3, slightly convex and suture, deep. Weak reticulate sculpture, replaced by weak spirals at base; 4 spirals and about 13 axials on the penultimate whorl. Aperture, rounded. Color, light yellow. It distinguishes from Alvania isolate (Laseron) in having weaker sculpture, smaller protoconch and lacking golden orange spots on shoulder. Distribution: At 110 meters depth off the Cook Strait, New Zealand is the fatherland. It is also found as beach drift at Lutao, Taiwan. Dimension: 1.4 x 0.5 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Ponder (1884), p. 147. Inventory: MLS -RI00006 7. Onoba delta (Powell, 1955) (Fig. 7) Synonymy: Subonoba delta Powell, 1955 in Powell (1979) Diagnosis: Shell, minute, oval-conic with protoconch of 2 smooth whorls. Mature whorls, 4, convex and suture, impressed. Sculpture of spiral cords with 6 spirals on the penultimate whorl. Aperture, rounded but moderately angled above. Color, white with some orange spots below sutures. Distribution: At 90 meters depth off Smares, New Zealand is the fatherland. It is also found as beach drift at Lutao, Taiwan. Dimension: 1.9 x 0.9 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Powell (1979), Fig. 23-1. Inventory: MLS -RI00007


Onoba isolata (Kay, 1979) (Fig. 8) Synonymy: Alvania isolate (Laseron, 1956) in Kay (1979) Diagnosis: Shell, minute, oval conic with protoconch of one and half smooth whorls. Mature whorls, 3, convex and suture, deeply impressed. Sculpture of coarse spirals, faintly beaded with 4-5 spirals on the penultimate whorl. Aperture, ovate, slightly oblique and outer lip, thin. Color, cream white splashed with brown on the spirals. Distribution: On reef and in beach drift in Hawaii. It is found off Lutao, Taiwan. Dimension: 2.0 x 1.1 mm. Remarks: Kay (1979) took this shell as Alvania isolata (Laseron, 1956). They are similar in form but differ in sculpture. Kay's species is coarsely spirally sculptured while Laseron's species is reticulately sculptured. Here, we name Kay's shell as Onoba isolata (Kay). Remarks: This is a new record in Taiwan. Reference for Identification: Kay ( 1 979), Fig. 27-C. Inventory: MLS -RI00008 9. Onoba mighelsi (Gould, 1870) (Fig. 9) Diagnosis: Shell, minute, oval-conic with apex, broadly conic. Mature whorls, 4, slightly convex; suture, channelled and beaded. Sculpture of broadly, shallowly granular spirals with interspace, narrow; 4-5 spirals on the penultimate whorl. Aperture, subcircular, moderately angled above and outer lip, thin. Color, pale white with a few reddish brown spots on shoulder. It distinguishes from Onoba isolata (Kay) as (a) this shell has broadly granular spirals while Onoba isolata (Kay) has narrower spirals with broader interspace, and (b) the spire whorls of this shell are flatly convex while Kay's shell is convex. Distribution: Gould's specimen was taken from the stomach of a haddock at Casco Bay. It is also found as beach drift at Lutao, Taiwan. Dimension: 2.0 x 1.1 rnrn. Remarks: Onoba sp. been reported in Chang (1998). This is a new record in Taiwan. Reference for Identification: Gould (1870), p.301, Fig. 570. Inventory: MLS -RI00009 10. Merelina solida Laseron, 1956 (Fig. 10) Diagnosis: Shell, minute, solid, opaque, oval-conic with protoconch, paucispiral, smooth. Mature whorls, 4, slightly convex and suture channelled. Sculpture of beaded spiral cords crossed by axial ribs; 3 spirals and about 14 ribs on the penultimate whorl. Aperture, subcircular with continuous duplicate peristoma and short lirae within. Outer lip, strongly variced and fimbriated. Distribution: Off Albany Passage,.Australia at depth of 110 meters is the fatherland. It is also found as beach drift in Lutao, Taiwan. Dimension: 2.4 x 1.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1 956), Fig. 131. Inventory: MLS -RI0000 11


11. Merelina succina Laseron, 1956 (Fig. 11) Diagnosis: Shell, minute, white, translucent, oval-conic with protoconch, paucispiral, smooth. Mature whorls, 3, moderately convex and suture, channelled. Clathrate sculpture with nodulose intersections. Aperture, subcircular with peristoma, duplicate; outer lip strengthen by smooth varix. It is close to Merelina solida Laseron. But this shell is stouter, translucent having a smooth outer lip while M. solida has fimbriated outer lip. Distribution: Off Darwin of Australia is the fatherland. It is also found off Lutao, Taiwan. Dimension: 2.0 x 1.O mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 132. Inventory: MLS -RI0000 11 12. Microstelma daedala A. Adams, 1863 (Fig. 12) Diagnosis: Shell, small, usually white, occasionally, orange banded, oval-conic with protoconch, paucispiral of 1+ smooth whorls and spire, subturreted. Mature whorls, 5-6, flatly convex and suture, undulate. Axial ribs, not reaching bottom; about 17 ribs on the penultimate whorl; spiral straie, dominant at base aperture, ovate with anterior canal, produced and outer lip, thin. Distribution: Goto Island, Japan at depth of 150-450 meters is the fatherland. It is also found off Lutao, Taiwan. Dimension: 4.6 x 2.0 mm (white specimen, upper pictures in Fig. 12); 4.2 x 2.2 mm (orange banded specimen, lower pictures in Fig. 12). Reference for Identification: A. Adams (1863), p. 348; Kuroda (1952), p. 130; Ponder (1984), p. 98. Inventory: MLS -RI0000 12 13. Microstelma thaumasia (Melvill et Standen, 1898) (Fig. 13) Synonymy: Rissoina (Morchiella) thaumasia Melvill et Standen, 1898 Diagnosis: Shell, small, white, elongate oval-conic with protoconch, paucispiral of 2+ smooth whorls. Mature whorls, 6-7 and suture, deeply impressed. Ribs, slightly flexous and oblique becoming weaker towards bottom; spiral straie dominant on the lower body whorl; about 16 ribs on the penultimate whorl. Aperture, lenticular with anterior canal, narrowly produced and posterior canal, angled above; outer lip, weakly variced. Distribution: Off Madras, India is the fatherland. It is common off Lutao, Taiwan. Dimension: 4.8 x 2.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Melvill and Standen (1898), pl. 1-3. Inventory: MLS -RI000013


14. Microstelmaformosus, sp. nov. (Fig. 14) Diagnosis: Shell, small, white, oval-biconic with apex, blunt, smooth and spire, subturreted. Mature whorls, 4, slightly convex and suture, undulate. Ribs raised with numerous spiral threads at intervals; about 10 ribs on each of the last two whorls. Aperture, ovate with anterior canal, produced and outer lip, thin. It distinguishes from Microstelma daedala A. Adams by having (a) 1 to 2 less mature whorls, (b) less ribs, about 10 on the penultimate whorls, and (c) more apparent spiral threads between ribs. Distribution: On beach of Lutao, Taiwan. Dimension: 3.6 x 2.0 mm (holotype), 3 . 8 ~1.8 mm; 3.2 x 1.8 mm and 3.5 x 1.8 mm (Paratypes). Remarks: Microstelma sp. A in Chang (1998). This species is named after its fatherland. Inventory: MLS -MOO00 14 15. Microstelma lutaoi, sp. nov. (Fig. 15) Diagnosis: Shell, small, white, translucent, oval-biconic; spire, subturreted with protoconch, paucispiral, of 2 convex whorls, smooth and glassy. Mature whorls, 6, rather convex and suture, deeply impressed. Ribs, slightly flexous and oblique with spiral striae, dominant on the lower body whorl; 13-14 ribs on the penultimate whorl. Aperture, ovate with outer lip, thin produced anteriorly. It is more slender and has axials, more flexous than Microstelma daedala and Microstelma formosus. Moreover, it is translucent. Distribution: On beach of Lutao, Taiwan. Dimension: 4.6 x 2.0 mm (holotype), 4.6 x 2.2 mm; 4 x 1.8 mm and 3 x 1.6 mm (Paratypes). Remarks: Microstelma sp. B in Chang, 1998. The name of this new species is after its fatherland. Inventory: MLS -RI0000 15

Key to Species of Genus Microstelma 1 2

3

Shell, stout ....................................................................................................................................... 2 Shell, elongate .................................................................................................................................3 Sculpture of more ribs (about 17 on the last whorls) and spirals, not apparent..................... daedala Sculpture of less ribs (about 10 on the last whorls) and spirals, apparent ..........................formosus Body whorl and aperture, broader; subtranslucent ................................................................... lutaoi Body whorl and aperture, narrower; white .......................................................................thaumasia

16. Schwartziella triticea (Pease, 1861) (Fig. 16) Synonymy: Rissoina triticea Pease, 1861 in Weinkauff (1885) Rissoina (Schwartziella) triticea Pease, 186 1 in Maes (1967); Cernohousky (1978)


Diagnosis: Shell, small, white, stoutly conical with protoconch, paucispiral. Mature whorls, 4-5. Sculpture, smooth of strong, keeled axial ribs; about 9 ribs on each of the last two whorls with interspaces, broader than the ribs. Aperture, ovate, angled above and thickly variced entirely. It looks like Schwartziella inconspicua Laseron but this shell is stouter with suture, indistinct and its ribs, nodulous on the shoulder. Distribution: Red Sea is the fatherland. It is distributed on reef or in sediments to depths of 15 meters throughout the Tropical Indo-Pacific from Hawaii, Taiwan, the Philippines, Cocos-Keeling Islands, Mauraitius, Ceylon to Red Sea. Dimension: 3.2 x 1.3 mm. Reference for Identification: Weinkauff (1885), Taf. 15b-Fig. 3; Maes (1 967), pl. 5G; Cernohousky (1978), pl. 11-10; Kay (1979), Fig. 29-2; Ponder (1884), p. 187. Inventory: MLS -RI0000 16 17. Schwartziella inconspicua (Brazier, 1877) (Fig. 17) Synonymy: Rissoina inconspicus Brazier, 1877 Diagnosis: Shell, minute, oval-conic; protoconch, 2-3 whorls, smooth, convex with its tip, tilted. Mature whorls, 5, convex and suture, impressed. Axial ribs, slightly flexous without spiral striae; 10-12 ribs on the penultimate whorl. Aperture, ovate and variced entirely. Distribution: This shell occurs in North Australia and it is also found off Lutao, Taiwan. Dimension: 2.7 x 1.3 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 2; Ponder (1984), pp.89, 187. Inventory: MLS -R1000017 18. Schwartziella sp. (Fig. 18) Diagnosis: Shell, minute, golden yellow, elongate ovate with spire turreted and apex, blunt. Mature whorls, 5, flatly convex, angulate to the nodulose sutural band. Strong flexous ribs from suture to suture or to the bottom with interspaces, deep and smooth; about 13 ribs on the penultimate whorl. Aperture elongate ovate, variced entirely. This shell resembles to Rissoina angusta Hedley, 1898 but that shell has spiral threads between ribs and aperture, not variced entirely. Distribution: It is found on the beach of Lutao, Taiwan. Dimension: 2.3x0.8 mm. Remarks: Schwartziella augusta (Hedley, 1898) in Chang (1998). It is probably a new species. Inventory: MLS -RI000018 19. Schwartziella gracilis (Pease, 1861) (Fig. 19) Synonymy: Rissoina gracilis Pease, 1861 in Garrett (1 873) Diagnosis: Shell, small, usually golden yellow, occasionally white, slender with protoconch, white of 3-4 whorls. Mature whorls, 6-7 and suture, impressed and margined beneath. Sculpture of flexous ribs from suture to suture or to the bottom


without spiral striae; about 16 ribs on penultimate whorl. Aperture, subovate nearly vertical, variced entirely. Distribution: At intertidal to shallow water under rock in Hawaii and Viti Isle. It is also found off Lutao, Taiwan. Dimension: 3.8 x 1 .O mm (golden yellow specimen, upper pictures in Fig. 19); 3.6 x 0.8 mm (white specimen, lower pictures in Fig. 19). Remarks: The white specimen may be a separate species because it has a taller protoconch of 4+ whorls. This is a new record in Taiwan. Reference for Identification: Garrett (1873), pl. 2-8; Kay (1979), Fig. 29-C. Inventory: MLS -RI0000 19 20. Pandalosia daminensis Laseron, 1956 (Fig. 20) Diagnosis: Shell, small, white, subpellucid elongate with turreted spire. Mature whorls, 5-6, flatly convex. Raised ribs, slightly oblique from suture to suture or to the base without spiral straie; about 14 ribs on the penultimate whorl. Aperture, semicircular; outer lip, variced thickly over anterior end becoming nodular on columella, but open at parietal wall. Distribution: Darwin, Australia is its fatherland and it is also found of Lutao, Taiwan. Dimension: 3.2 x 1.4 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 6. Inventory: MLS -RI000020 21. Pandalosia catesbyana (Orbigny, 1842) (Fig. 21) Synnymy: Rissoina (Schwartziella) catesbyana Orbigny, 1842 in Desjardin (1949) Diagnosis: Shell, ivory white, oval-conic with apex, blunt. Mature whorls, 5, slightly convex and suture, undulate and margined beneath Ribs, broad, flexous from suture to suture or to the base without spiral striae; about 10 ribs on the penultimate whorl. Aperture, small; semicircular with outer lip, variced over to columella. Distribution: It was found as fossil in Cuba but its recent species is found off Lutao, Taiwan. Dimension: 3.8 x 1.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Desjardin (1949), pl. ix-7. Inventory: MLS -MOO002 1 Pandalosia ephamilla (Watson, 1886) (Fig. 22) Synonymy: Rissoina (Rissolina) ephamilla Watson, 1886 in Cernohousky (1978) Rissoina ephamilla Watson, 1886 in Kay (1979) Schwartziella (Pandalosia) ephamilla (Watson, 1886) in Ponder (1984) Diagnosis: Shell, minute, translucent, elongate with blunt apex. Mature whorls, 6, shouldered and suture, impressed. Ribs, oblique from suture to suture or to the base without spiral straie; 1 1 - 12 ribs on the penultimate whorl. Aperture, semicircular; outer lip, thickly variced over to columella.


Distribution: It is distributed in Tropical Indo-Pacific from Hawaii, Marshalls to CocosKeeling Id.; intertidal to 50 meters depth in sediment. It is found off Lutao, Taiwan. Dimension: 2.4 x 0.8 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Watson (1886), pl. XLVI-6; Maes (1967), pl. 5D; Cernohousky (1978), p. 45; Kay (1979), Fig. 29B; Ponder (1984), p. 188. Inventory: MLS -RI000022 23. Pandalosia lutaoi, sp. nov. (Fig. 23) Diagnosis: Shell, small, white, subtranslucent like wax-made with apex, lowly domed. Mature whorls, 4-5, and suture, indistinct. Ribs, low, broad with 9 ribs on the penultimate whorl. Aperture, semicircular, heavily variced over to columella leaving parietal wall open. Distribution: On beach of Lutao, Taiwan. Dimension: 4.8 x 2.2 mm (holotype); 6.4 x 2.6 mm and 5.8 x 2.4 mm (Paratypes). Remarks: Pandalosia wax n. sp. in Chang (1998). This new species is named after its fatherland. Inventory: MLS -R1000023 24. Pandalosia moerchiella, sp. nov. (Fig. 24) Diagnosis: This shell looks like Pandalosia lutaoi. But this shell has crested ribs on earlier whorls whereas P. lutaoi has broad, shallow ribs on all whorls. Moreover, this shell has impressed sutures while P. lutaoi has ribs over sutures. Distribution: On beach of Lutao, Taiwan. Dimension: 6.6 x 2.7 mm (holotype); 6.3 x 2.2 mm and 6.6 x 2.6 mm (paratypes). Remarks: Pandalosia sp. B in Chang (1998). This species is named for its similarity to Moerchiella shells in shape and sculpture. Inventory: MLS -RI000024

Key to Species of Genera Schwartziella and Pandalosia 1 2

3 4

5 6

7

Aperture, variced entirely (Schwartziella) ......................................................................................2 Aperture, variced with opening at parietal wall (Pandalosia) ........................................................ 5 Sutures, margined ............................................................................................................................ 3 Sutures, not margined ....i ................................................................................................................. 4 Stouter; ribs, more raised ........................................................................................Schwartziea sp. Slender; ribs, shallow ........................................................................................................S gracilis Suture, impressed; ribs, smooth .................................................................................S. inconspicua Suture, indistinct; ribs, nodulous on shoulder ....................................................................S. triticea Whorls, slightly convex; varix on columella, nearly smooth ........................................................ 7 Whorls, shouldered; varix on columella, nodulous ................................................... P. darwinensis Spire, elevated; suture, indistinct .....................................................................................................8 Spire, conical; suture, distinct ...................................................................................... P. catesbyana Ribs, shallow on all whorls .................................................................................................. P. lutaoi Ribs, crested on earlier whorls ................................................................................... P. moerchiella


Rissoina ambigua (Gould, 1849) (Fig. 25) Synonymy: Pyramidella ambigua Gould, 1849 in Johnson (1964) Rissoina (Rissoina) ambigua (Gould, 1849) in Ponder (1 984) Diagnosis: Shell, solid, usually white, occasionally brown banded; oval-conic with protoconch of 3 smooth whorls. Mature whorls, 6-7, flatly convex with body whorl, inflated slightly. Longitudinal axial ribs with interspace, nearly equal and numerous fine spiral striae under high magnification; 22-25 ribs on the penultimate whorls. Aperture semicircular; columella, oblique truncated with nodule anteriorly; anterior canal, broad, oblique; outer lip, variced. Operculum, horny with a peg (Ponder, 1984). Distribution: Poumotus Id., New Holland is the fatherland. It is distributed in Tropical Indo-Pacific from Seychelles of Indian Ocean to Marshalls, intertidal to subtidal on reef. It is abundant in Taiwan. Dimension: 5.6 x 2.1 mm (white specimen, upper pictures in Fig. 25); 6.4 x 2.2 mm (colored specimen, lower pictures in Fig. 25). Reference for Identification: Weinkauff (1885), Taf. 9-1; Maes (1967), pl. 5M; Cernohousky (1 978), pl. 11-6; Kay (1979), Fig. 29A; Ponder (1 984), p. 178. Inventory: MLS-RI000025

26. Rissoina stricta Menke, 1850 (Fig. 26) Synonymy: Rissoina (Rissoina) stricta Menke, 1850 in Keen (1 97 1) Diagnosis: Shell resembles Rissoina ambigua (Gould) but having less ribs with broader interspace; 16-18 ribs on the penultimate whorl. Distribution: It occurs in Gulf of California and south to Marias Id. But it is also found off Lutao, Taiwan. Dimension: 5 x 1.8 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Weinkauff (1 885), Taf. 15d- 12; Keen (1 97 l), sp. 27 1. Inventory: MLS -RI000026 Rissoina materinsulae Pilsbry, 1904 (Fig. 27) Diagnosis: Shell, solid, white, oblong-acuminate with the outlines of the spire, convex. Sculpture of many longitudinal ribs, about 25 on the penultimate whorl; the intervals transversely striated. The apex, paucispiral of 2 smooth whorls and mature whorls, 6, slightly convex and separated by a shallow suture. The last whorl is swollen. The aperture is semiovate and outer lip, thickened and vericed a little, advanced below. Columellar margin, moderately concave, truncate anteriorly with a nodule. It looks like Rissoina ambigua (Gould) but the outlines of the ambigua is not so convex and the aperture of the ambigua is smaller, not advanced below. Distribution: Hahajima, Ogasawara of Japan is the fatherland. It was reported in Taiwan by Kuroda (1 941). Dimension: 7.2 x 2.4 mm. Reference for Identification: Pilsbry (l904), pl. 5, Fig. 43; Kuroda (1941), sp. 185. Inventory: MLS -RI000027


28. Rissoina sp. A (Fig. 28) Diagnosis: Shell, small, white, cylindrical conic with protoconch, lowly domed of 1+ whorl and the spire, subturreted. Mature whorls, 5, flat and suture, slightly impressed. Longitudinal axials with interspace, nearly equal and numerous fine spiral striae under high magnification; 22-25 ribs on the penultimate whorls. Aperture, narrowly ovate; columella, oblique, concave with nodule anteriorly; anterior canal, broad, oblique; outer lip, thickly variced. It is close to Rissoina ambigua (Gould). But (a) this shell has a lowly domed protoconch while the ambigua has a papillary protoconch of 3 smooth whorls, (b) this shell is stouter with only 5 mature whorls while the ambigua has 7 whorls, and (c) this shell has a narrower ovate aperture and outer lip, variced very thickly while the ambigua has a semicircular aperture and outer lip backed by varix but not very thick. Distribution: On beach of Lutao, Taiwan. Dimension: 5.0 x 2.2 mrn. Remarks: It is probably a new species. Inventory: MLS-RI000028 29. Rissoina fortis C. B. Adams, 1852 (Fig. 29) Diagnosis: Shell looks like the ambigua but (a) this shell is more slender with flat whorls and a shorter, narrower body whorl, and (b) this shell has less ribs in sculpture, 18-20 on the penultimate whorl. Distribution: Tabago, Panama is the fatherland and it is distributed in the Philippines and Lutao, Taiwan. Dimension: 5.6 x 2.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1 860), sp. 25; Weinkauff ( I 885), Taf. 8-8. Inventory: MLS-RI000029 30. Rissoina similis Fuchs, 1869 (Fig. 30) Diagnosis: Shell, white, cylindrical with apex, eroded. Mature whorls, 7, flat and suture, a little impressed; longitudinal ribs with nearly equal interspaces from suture to the suture or to base; about 18 ribs on the penultimate whorl. Aperture, small, ovate with columella, concave and outer lip, heavily thickened. Distribution: It was fossil in Europe but it is also found off Lutao, Taiwan. Dimension: 5.6 x 2.0 rnrn. Remarks: The aperture of this species is smaller than all the above Rissoina shells and its anterior canal, broad anteriorly, not oblique to the left side as the above Rissoina shells. This is a new record in Taiwan. Reference for Identification: Fuchs (1 969), Taf. 111 14-15. Inventory: MLS-RI000030 31. Rissoinapusilla Brocchi in Schwartz, 1860 (Fig. 31) Diagnosis: Shell, white elongate with blunt apex and a body whorl, nearly as tall as the spire. Mature whorls, 4-5, slightly convex and suture, indistinct and subsuture, tight.


Ribs, narrow, flexous; 22-26 ribs on the penultimate whorl. Aperture, large, semicircular with anterior end, broad; inner lip, heavily calloused; columella, oblique with a nodule at anterior end; outer lip, thick, advanced outwards. Distribution: Red Sea is the fatherland. It occurs in Mauritius, Tahiti, Upolu, Sandwich Id. and it is also found off Lutao, Taiwan. Dimension: 6.8 x 3.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1 860), sp. 29; Weinkauff (1885), Taf. 9-2. Inventory: MLS-RI00003 1

32. Rissoina rissoi Audouin in Weinkauff, 1885 (Fig. 32) Diagnosis: Shell, small, white oval-conic with protoconch, papillate. Mature whorls, 6, convex and suture, impressed. Ribs, flexous on the convex whorls; about 18 ribs on the penultimate whorl; fine spiral striae at the base. Aperture, lenticular with canal, broad and produced; inner lip, calloused and outer lip, thickened and variced. Distribution: Red Sea is the fatherland. It is found off Lutao, Taiwan and distributed in West Pacific. Dimension: 5.0 x 2.1 rnrn. Remarks: This is a new record in Taiwan. Reference for Identification: Weinkauff (1885), Taf. 15-13. Inventory: MLS-RI000032. 33. Rissoina pulchella Brazier, 1877 (Fig. 33) Synonymy: Rissoina honoluluensis Watson, 1886 in Laseron (1956) Austrosina pulchella (Brazier, 1877) in Laseron (1956) Diagnosis: Shell, small, white with elevated spire. Protoconch of 3 convex whorls with granular spiral striae. Mature whorls, 5, convex and suture barely impressed. Ribs, narrow with broad interspaces; 16- 18 ribs on the penultimate whorl. Aperture, small, ovate with columella, concave; posterior canal; acutely angled; inner lip, calloused and outer lip, thick, heavily variced. Distribution: It is distributed in Hawaii and West Pacific; intertidally to 65 meters deep. It is common off Lutao, Taiwan. Dimension: 4.4 x 1.7 rnm. Remarks: This is a new record in Taiwan. Reference of Identification: Laseron (1956), pl. XLVI-9, F ig. 13; Kay (1979), Fig. 29E. Inventory: MLS-RI000033 34. Rissoina quinita (Laseron, 1956) (Fig. 34) Synonymy: Austrosina quinita Laseron, 1956 Diagnosis: Shell, small, elongate, conical, solid, white with protoconch, conic of 3 smooth short whorls. Mature whorls, 5, flatly convex, angulate at both sutures and suture, moderately impressed. Sculpture of axial ribs, about 12 on the penultimate whorl. Aperture, semiovate with slightly arcuate columella; anterior canal, broad; posterior canal, acutely angled; outer lip variced. It is very close to Rissoina


pulchella but its axial ribs is heavier, angulate and its whorls, flatly convex, not as convex as R. pulch Ila. Distribution: Christ as Id., Australia is the fatherland. It is also found off Lutao, Taiwan. Dimension: 5.0 x 1.9 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 14. Inventory: MLS-RI000034

4?

35. Rissoina taiwanica, sp. nov. (Fig. 35) Diagnosis: Shell, white, slender with a tall spire and protoconch, papillate of 2 smooth whorls. Mature whorls, 7-8, flatly convex, angulate at upper suture and suture, impressed. Rib sculpture with spiral striae, dominant on lower body whorl; 11-12 ribs on the penultimate whorl. Aperture, lenticular with a broad shallow canal, anteriorly; columella, slightly concave and outer lip, variced. It resembles Rissoina quinita (Laseron) but the quinita is not so slender and its aperture is smaller, semicircular while this shell has a lenticular aperture. Distribution: It is common off Lutao, Taiwan. Dimension: 6.6 x 1.8 mm (holotype); 5.8 x 2 mm (paratype). Remarks: Rissoina delicata n. sp. in Chang (1998). It looks like Pandalosia delicatula Laseron, 1956 which is smooth but this shell has spiral striae on the body whorl. Moreover, the varix of this shell does not reach columella while the Pandalosia shell does. The name of this species is after its fatherland. Inventory: MLS-RI000035 36. Rissoina bonneti Cossmann, 1910 (Fig. 36) Diagnosis: Shell, small, white, elongate conic with spire, nearly straight-sided and apex, blunt. Mature whorls, 5, flatly convex. and suture, undulate. Ribs, broad and shallow with spiral threads at bottom; about 14 ribs on the penultimate whorl. Aperture, semicircular and outer lip, thickened and variced. Distribution: It was fossil in New Guinea but its recent shell is found off Lutao, Taiwan. Dimension: 4.2 x 1.8 mrn. Remarks: This is a new record in Taiwan. Reference for Identification: Cossmann (19 lo), pl. 111-10, 11. Inventory: MLS-RI000036 37. Rissoina tibicen Melvill, 1912 (Fig. 37) Diagnosis: Shell, white, glossy, elongate with a tall spire, straight-sided and apex, decollate. Mature whorls, 6-7, flatly convex and suture, linear. Ribs, broad and shallow overriding weak spiral straie all over; about 12 ribs on the penultimate whorl. Aperture, lenticular subovate; inner lip, calloused; outer lip, variced thickly. It is close to Rissoina bonneti Cossman. But this shell has (a) a lenticulate aperture while the bonneti has a smaller semicircular aperture, and (b) the suture of this shell is linear while the bonneti has suture, slightly impressed with subturreted spire whorls.


Distribution: Oman is the fatherland. It is found off Lutao, Taiwan. Dimension: 4.6 x 1.8 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Melvill(19 12), pl. XII-9. Inventory: MLS-RIOO 037

b\_

38. Rissoina scalariformis C. B. Adams, 1852 (Fig. 38) Diagnosis: Shell, small, white, oval-conic with protoconch, snow-white of 2+ convex whorls and spire, subturreted. Mature whorls, 5, convex and suture, undulate. Ribs, narrow, raised with numerous spiral threads all over the interspace; 9-10 ribs on the penultimate whorl. Aperture, subovate, angled above with outer lip, weakly variced. It looks like SchwartzieIIa triticea (Pease) but this shell has spiral threads all over and its varix not reaching columella while the triticea is smooth having an entire varix of the aperture. Distribution: Panama is the fatherland. It is distributed in Mauritius, Reunion, Red Sea, Polynesia. It was reported in Taiwan by Kuroda (1941). Dimension: 4.9 x 2.2 mm. Reference for Identification: Schwartz (1 860), sp. 24; Weinkauff (1 885), Taf. 8-7; Kuroda (1 941), sp. 187. Inventory: MLS-RI000038 39. Rissoina helenae E. A. Smith, 1890 (Fig. 39) Diagnosis: Shell, small, white, oval-conic with apex blunt and spire, narrow, subturreted. Mature whorls, 4, flatly convex and suture, impressed, undulated. Raised ribs with interspaces, smooth, slightly broader than rib width; about 10 ribs on the penultimate whorl. Aperture, semicircular with inner lip, calloused and outer lip, thickened and variced. It looks like Rissoina scalariformis but this shell has a narrower spire and lacks the apparent spiral threads. Distribution: St. Helena is the fatherland, but it is also found off Lutao, Taiwan. Dimension: 5.0 x 2.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: E. A. Smith (1 890), pl. XXIII-38. Inventory: MLS-RI000039 40. Rissoina thatcheria, sp. nov. (Fig. 40) Diagnosis: Shell, small, white, elongate with turreted spire and apex, blunt. Mature whorls, 6, flatly convex. Axial ribs, flexous overriding spiral threads; about 12 ribs on the penultimate whorl. Aperture, semicircular with a broad canal at anterior end and outer lip, simple. It looks like Pandalosia ephamilla (Watson) but this shell has a more turreted spire and lacks the basal fold. Distribution: On beach of Lutao, Taiwan. Dimension: 3.2 x 1.0 mm (holotype); 3 . 4 1.2 ~ mm and 3.2 x 1.3 mm (paratypes). Remarks: Rissoina sp. C been reported in Chang (1 998). The name of this species is for this shell looking like Tharcharia mirabilis Angas in shape.


Inventory: MLS-RI000040 41. Rissoina evanida (Laseron, 1956) (Fig. 41) Synonymy: Austrosina evanida Laseron, 1956 Diagnosis: Shell, small, white or yellowish, oval-conic with protoconch, paucispiral of 2+ smooth whorl . Mature whorls, 5, slightly convex with body whorl, inflated and suture, impressed. Ribs, narrow, oblique fading at the base; 16-18 ribs on the penultimate whorl; s iral striae all over, dominant on the lower body whorl. Aperture, subovate with outer lip, weakly variced. Distribution: Chrismas Is. is the fatherland. It occurs in the Philippines and Lutao, Taiwan. Dimension: 5.0 x 2.1 rnrn. Remarks: This shell looks like Rissoina otohimeae (Kosuge) shown as below. But R. otohimeae has many spiral cords at the bottom while this shell has a nodulous fold at base Kosuge (1965) erroneously used "Rissoina (Schwartziella)" for his "otohimeae" Schwartziella always has an entire varix around the aperture and the ribs always reach the bottom without spirals at base and the interspaces are smooth. This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 15. Inventory: MLS-RI00004 1

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Rissoina otohimeae (Kosuge, 1965), after Kosuge (1965)

42. Rissoina sp. B (Fig. 42) Diagnosis: Shell, minute, light-brown, oval-conic with protoconch, smooth, domed. Mature whorls, 4-5, convex and suture, deeply impressed undulate. Sculptured with arcuate axial ribs fading at base; spiral striae in the interspace, dominant on the lower body whorl. About 18 ribs on the penultimate whorls. Aperture, semicircular with columella, slightly arched and outer lip, thickened. The close species is Rissoina evanida Laseron. The evanida has more inflated body whorl and conical spire whereas this shell has convex spire whorls with deeply impressed sutures. Moreover they have different protoconch. Distribution: On beach of Lutao, Taiwan. Dimension: 2.5 x 1.2 mm.


Remarks: It is probably a new species. Inventory: MLS -RI000042 Rissoina lutaoi, sp. nov. (Fig. 43) Diagnosis: Shell, minute, white, occasionally yellow, oval-conic with apex, blunt. Axial ribs, narrow wit interspaces, broader than its rib width overriding microscopic spiral straie; 20- 4 ribs on the penultimate whorl. Aperture, semicircular with columella, slightly boncave and outer lip, weakly variced. It looks like Rissoina ambigua Gould but this shell is stouter with whorls, more inflated. Moreover, this shell is much smaller and rather uniform in size ranging 2.5-2.8 mm. Distribution: It is common off Lutao, Taiwan. Dimension: 2.7 x 1.2 mm (holotype); 2.8 x 1.3 mm; 2.5 x 1.1 mm (paratypes). Remarks: Rissoina sp. in Chang (1998). This species is named after its fatherland. Inventory: MLS-RI000043

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Key to Species of Genus Rissoina Axial ribs uniformly strong ............................................................................................................. 2 Axial ribs fading at base ................................................................................................................ 17 Axials, narrow, longitudinal with interspaces, nearly equal ............................................................3 Axials, flexous or broad ..................................................................................................................8 Outline of later whorls, convex ....................................................................................................... 4 Outline of later whorls, nearly straight ............................................................................................7 Aperture, smaller, not advanced below ...........................................................................................5 Aperture, larger, advanced below ................................................................................materinsulae Ribs, more than 22 on penultimate whorl ........................................................................................ 6 Ribs, less than 18 on penultimate whorl .................................................................................. stricta Protoconch, papillary of 3 whorls; outer lip, not very heavily variced ...............................ambigua Protoconch, lowly domed; outer lip, very thickly variced .......................................... Rissoina sp. A Earlier spire, elevate, aperture, smaller ................................................................................... similis Earlier spire conic; aperture, large ............................................................................................. fortis Ribs, broad and shallow .................................................................................................................. 9 Ribs, narrow and raised ................................................................................................................. 10 Aperture, lenticulate; suture, linear ........................................................................................ tibicen Aperture, semicircular; suture, undulate ................................................................................ bonneti Shell, stout ..................................................................................................................................... 11 Shell, elongate ............................................................................................................................... 12 Spire, slender; spiral threads, not apparent ............................................................................helenae Spire, broader; spiral threads, apparent ........................................................................ scalartyormis Spire, not distinctly turreted ..........................................................................................................13 Spire turreted .................................................................................................................... dhatcheria Aperture, smaller, narrower anteriorly .......................................................................................... 14 Aperture, larger, broad anteriorly ........................................................................................... pusilla Aperture, lenticulate ...................................................................................................................... 15 Aperture, smaller, semicircular ......................................................................................................16 Shell, slender of 7-8 teleoconch, flatly convex .................................................................. taiwanica . Shell, oval conic of 6 teleoconch, convex .................................................................................rtssot Whorl, flatly convex and suture, distinct ................................................................................quinita

.


17 18

Whorls, convex and suture, not very distinct .....................................................................pulchella Shell, stouter; minute, less tha 3 mm in length ............................................................................18 Shell with conic spire; small, a L m ............................................................................. evanida Ribs, more and longitudinal......................................................................................................Iutaoi Ribs, less, flexous overhanging the suture .................................................................Rissoina sp. B

44. Rissolinaplicatula (Gould, 1861) (Fig. 44) Synonymy: Rissoina plicatula Gould, 1861 Rissoina (Rissolina) plicatula Gould, 1861 in Ponder (1984) Diagnosis: Shell, small, white with spire, slender, conical and protoconch of 2+ smooth whorls. Mature whorls, 7 slightly convex and suture, moderately impressed. Rib sculpture with scarcely spiral striae but having a broad basal fold; about 17 ribs on the penultimate whorl. Aperture, semicircular; anterior canal, oblique and rather deep; outer lip, weakly variced. Distribution: Bonin Id., Okinawa is the fatherland. It is distributed in West Pacific and common off Lutao, Taiwan. Dimension: 5.2 x 2.3 mrn. Remarks: Ponder's shell (1984, p.183A) having a double spirals on the body whorl is some other rissoid but not Rissolina plicatula (Gould). Both the Ponder's shell and the holotype are shown as follows for comparison. Reference for Identification: Johnson (1964), pl. 15-5, holotype; Ponder (1984), p. 183. Inventory: MLS -RI000044

Rissolina plicatula (Gould) holotype, 6 mm

Rissolina plicatula (Gould) 4.8 mm, after Ponder, (1984)

45. Rissolina elegantissima (Orbigny, 1853) (Fig. 45) Synonymy: Rissoina elegantissima Orbigny, 1853 Diagnosis: Shell, small, white, translucent with spire, slender, conical and protoconch, paucispiral of 2+ smooth whorls. Mature whorls, 7, slightly convex and suture, slightly impressed. Sculpture of ribs with subsuture margined, resting on a beaded basal fold; 18 ribs on the penultimate whorl. Aperture, semicircular with anterior canal, oblique, rather broad and deep; outer lip, variced. This shell is close to


Rissolina plicatula (Gould). It distinguishes from the plicatula by its translucency and its subsuture, m a r g i q Distribution: Antilles and ~aiti-i; the fatherland. It distributed in West Indies but it is also found off Lutao, Taiwan. Dimension: 4.6 x 1.8 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1860), sp. 12; Weinkauff (1885), Taf. 7-6; Desjardin (1949), pl. IX-3. Inventory: MLS -R1000045 46. Rissolina turricula (Pease, 1861) (Fig. 46) Synonymy: Rissoina turricula Pease, 1861 Rissoina (Rissolina) turricula Pease, 1861 in Cernohousky (1978) Diagnosis: Shell, white, occasionally colored, elongate conic with turreted spire and protoconch, paucispiral of 2 smooth whorls. Mature whorls, 6, flatly convex. Strong ribs terminating at a basal furrow then a nodulose basal fold below it; 12-14 ribs on the penultimate whorl; Aperture, small, semicircular; anterior canal, broad, deep and oblique; outer lip, variced and fimbriated. Distribution: Sandwich Id. is the fatherland. It is common in Tropical Indo-Pacific from Red Sea, Ceylon, Mauritius, the Philippines and Lutao, Taiwan to Hawaii; intertidal to shallow water on reef or on sediment. Dimension: 4.2 x 1.6 mm (white specimen, Fig. 46); 5.8 x 1.8 mm (colored specimen). Reference for Identification: Weinkauff (1885), 1%-6; Maes (1967), pl. 5H; Kay (1965), pl. 11-10; Cernohousky (l978), pl.11-8. Inventory: MLS -RI000046 47. Rissolina crassa (Angas, 1871) (Fig. 47) Synonymy: Rissoina crassa Angas, 187 1 Rissoina (Rissolina) crassa Angas, 187 1 in Ponder ( 1984) Diagnosis: It looks like Rissolina turricula (Pease) but this shell has a taller spire with more mature whorls (7-8) and a smaller aperture. Moreover its protoconch is smaller, papillary whereas that of the turricula is paucispiral, broader. Distribution: It is distributed in Red Sea, South China Sea and Lutao, Taiwan. Dimension: 5.8 x 2.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Ponder (1984), p. 183. Inventory: MLS -R1000047 48. Rissolina decapitata (Laseron, 1956) (Fig. 48) Synonymy: Costalynia decapitate Laseron, 1956 Diagnosis: Shell, small, white and translucent oval-conic. Apex, truncate at first sight but there is a large nucleus immersed in the summit. Mature whorls, 5, convex and suture, moderately impressed. Sculpture of oblique axial ribs, about 16 on the penultimate whorl; a strong nodulous basal fold below a basal furrow where axial


ribs terminate. Aperture, semicircular with columella, slightly concave; anterior canal, oblique, rather deep and outer lip, variced. Distribution: Michaelmas Cay, Australia is the fatherland. It is also found off Lutao, Taiwan. / Dimension: 4.6 x 2.0 mm. Remarks: This is a new rec rd in Taiwan. Reference for Identification: Laseron (1956), Fig. 20. Inventory: MLS -RI000048

b

49. Rissolina scalariana (A. Adams, 1851) (Fig. 49) Synonymy: Rissoina scalariana A. Adams, 1851 Diagnosis: Shell, white, elongate conical with subturreted spire and protoconch, paucispiral of 2 smooth whorls. Mature whorls, 6-7, slightly convex, subangulate at upper suture. Sculpture of distant narrow, raised axial ribs, 7-8 on the penultimate whorl; numerous spiral threads all over. Aperture, irregular ovate for the immature specimen but the basal fold has formed. The mature shell after Weinkauff (1885) is shown as follows for comparison. Distribution: Burias Id. of the Philippines is the fatherland and it is found off Lutao, Taiwan. Dimension: 5.2 x 2.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: A. Adams (1951), p. 265; Schwartz (1860), sp. 19; Weinkauff (1 885), Taf. 8-3. Inventory: MLS -R1000049

Rissolina scalariana (A.Adams), 8.5 mm, after Weinkauff (1885)

50. Rissolina praecida (Laseron, 1956) (Fig. 50) Synonymy: Fractoralla praecida Laseron, 1956 Rissoina (Rissolina) praecida (Laseron, 1957) in Ponder (1 984) Diagnosis: Shell, white cylindrical conic with turreted spire and an obtuse, domed apex. Mature whorls, 4-5, flat, biangulate at sutures which are deeply impressed and beaded. Strong ribs resting on a basal furrow, then a strong smooth fold below it; 1314 ribs on the penultimate whorl. Aperture, semicircular; anterior canal, oblique and deep; outer lip, thickly variced and fimbriated.


Distribution: Darwin, Australia is the fatherland. It is also found off Lutao, Taiwan. Dimension: 8.4 x 3.3 mm. Remarks: This is a new record in Taiw Reference for Identification: Laseron Fig. 27; Ponder (1 984), p.83. Inventory: MLS -RI000050 1. Rissolina sp. (Fig. 51) Diagnosis: Shell, dark with both ends, white; oval-conic with protoconch of 2+ smooth convex whorls. Mature whorls, 5-6, slightly convex. Sculpture of ribs, narrow, obliquely parallel resting on a nodular basal fold overriding numerous weak spiral striae; 13-14 ribs on the penultimate whorl. Aperture, semicircular; columella, slightly concave with a lip anteriorly; anterior canal, oblique, broad and deep; outer lip, thickly variced. Distribution: On beach of Lutao, Taiwan. Dimension: 4.7 x 2.2 mm. Remarks: Rissolina sp. D in Chang (1998). It is probably a new species. Inventory: MLS -R100005 1 52. Rissolina cardinalis (Brazier, 1877) (Fig. 52) Synonymy: Rissoina cardinalis Brazier, 1877 Rissoina mercurialis Watson, 1886 in Laseron (1956) Costalynia cardinalis (Brazier, 1877) in Laseron (1 956) Rissoina (Rissolina) cardinalis Brazier, 1877 in Ponder (1884) Diagnosis: Shell, white, oval-conic with spire, elevated and apex, blunt. Mature whorls, 6, slightly convex and suture, weakly impressed. Sculpture of flexous axial ribs, resting on a nodular basal fold, microscopic spiral straie all over; 9 ribs on the penultimate whorl. Aperture, semicircular; anterior canal, oblique, deep; outer lip, variced. Distribution: Cape Grenville, Australia is the fatherland. It is found off Lutao, Taiwan and distributed in West Pacific. Dimension: 5.6 x 2 mm. Remarks: Brazier's species was not figured. Laseron's figure (C41440) was figured by Hedley who reviewed and figured all the types of Brazier's species in Macleay Museum. Ponder's specimen is a different shell having a double spirals on the body whorl (p.183 in Ponder, 1984). This article follows both Laseron's and Ponder's shells are shown as follows. This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 16; Ponder (1 884), p. 183. Inventory: MLS -RI000052


Rissolina cardinalis (Brazier) 6.5 mm, after Ponder (1984)

Rissolina cardinalis (Brazier) 6.0 mm, after Laseron (1956)

53. Rissolina costulata (Dunker,l861) (Fig. 53) Synonymy: Rissoina costulata Dunker, 1861 Rissoina (Rissolina)costulata (Dunker, 186 1) in Kosuge (1965) Diagnosis: Shell, white, oval-conic with apex, flatten. Mature whorls, 6, slightly convex and suture, narrowly channeled. Ribs, slightly oblique, scarcely spirally striated; about 15 ribs on the penultimate whorl; a smooth basal fold becoming hump near aperture. Aperture, semicircular and outer lip, thick and variced. Distribution: It is distributed between Japan and Taiwan. Dimension: 5.3 x 2.3 mm. Reference for Identification: Dunker (1 861), Tab. 11-11; Habe (196 I), pl. 10- 16; Kosuge (1965), pl. 15-3; Kuroda (l971), pl. 107-10. Inventory: MLS -RI000053 54. Rissolina humpa, sp. nov. (Fig. 54) Diagnosis: Shell, small, white, oval-conic with apex, flatten. Mature whorls, 4, slightly convex but suture, indistinct. Ribs, slightly flexous, scarcely spirally striated; about 16 ribs on the penultimate whorl; a smooth basal fold becoming hump near aperture. Aperture, semicircular and outer lip, thick and variced. It looks like Rissolina costulata (Dunker), but this shell is stouter with less whorls. Moreover, its suture is indistinct while the suture of R. costulata is channeled. Distribution: On beach of Lutao, Taiwan. Dimension: 4.2 x 2.1 mm (holotype); 4.6 x 2.1 mm (paratype). Remarks: Rissolina sp. A been reported in Chang (1998). The name of this species is for its prominent hump at the end of the basal fold. Inventory: MLS -RI000054 55. Rissolina ovalis, sp. nov. (Fig. 55) Diagnosis: Shell, small, oval with convex outline and apex, blunt. Mature whorls, 4 and suture, pitted between the overhanging ribs. Strong ribs with microscopic spiral straie and a nodular fold at the base; about 10 ribs on the penultimate whorl. Aperture, semicircular; anterior canal, shallow and broad; outer lip, variced. It


differentiates from the above R. humpa by the stouter form, pitted suture and basal fold, nodulous not smooth. Distribution: On beach of Lutao, Ta'wan. Dimension: 3.6 x 2.0 mm (holotype); 8 x 2 mm; 3.6 x 1.8 mm (paratypes). Remarks: Rissolina sp. B in Chang ( 998). The name of this species refers its oval shape. Inventory: MLS -RI000055

13.1

56. Rissolinaplicata (A. Adams, 1851) (Fig. 56) Synonymy: Rissoina plicata A. Adams, 185 1 Rissoina denticulata Montrouzier in Schwartz (1 860); Weinkauff (1885) Diagnosis: Shell, white with spire, subturreted and protoconch, paucispiral of 2 smooth whorls. Mature whorls, 5, flatly convex. Ribs, raised with broader interspace, usually having apparent spiral striae, occasionally smooth; basal fold, weak; 9-10 ribs on the penultimate whorl. Aperture, semicircular with inner lip, calloused and outer lip, thickened, variced. Distribution: Masbate Id. of the Philippines is the fatherland. It is abundant in Java, Indonesia and Lutao, Taiwan. Dimension: 5.2 x 2.2 mm; 5.0 x 2.2 rnm. Remarks: Schwartz (1960) used the specimen of 4 mature whorls, nearly smooth between ribs as a separate species, namely, Rissoina denticulata. Weinkauff (1885) combined them together. Reference for Identification: A. Adams (195 l), p.264; Schwartz (1 860), sp. 2 1 ; Weinkauff (1 885), Taf. 8-5. Inventory: MLS -RI000056 57. Rissolinafimbriata (Souverbie, 1872) (Fig. 57) Synonymy: Rissoinafimbriata Souverbie, 1872 Diagnosis: Shell, small, cream white, subtranslucent, slender with apex, flattened. Mature whorls, 4-5, convex and suture, distinctly impressed. Sculptured with arcuate axial ribs with nodulose oblique fold at the base; about 18 ribs on the penultimate whorl. Aperture, semicircular with the outer lip, thickened and variced. Distribution: Art Id., New Caledonia is the fatherland. It is also found off Lutao, Taiwan and distributed in Tropical West Pacific, intertidal. Dimension: 4.3 x 1.6 rnm. Remarks: This is a new record in Taiwan. Reference for Identification: Weinkauff (1885), Taf. 14-6; Cernohousky (1978), pl. 119. Inventory: MLS -I21000057 58. Rissolina distant (Anton, 1839) (Fig. 58) Synonymy: Rissoina distant Anton, 1839 Diagnosis: Shell, white, elongate conic with apex, blunt and spire, subturreted. Mature whorls, 6, flatly convex, shouldered and suture, undulate. Raised ribs with scarcely


spiral straie and a strong smooth basal fold; 8-9 ribs on the penultimate whorl. Aperture, semicircular; anterior canal, broad and shallow. Distribution: It occurs in the Philippiyes and Lutao, Taiwan. Dimension: 6.6 x 2.6 mm. Reference for Identification: (1 860), sp. 17; Weinkauff (1 885), Taf. 5-5, 6, 7. Inventory: MLS -RI000058

59. Rissolina laseroni, sp. nov. (Fig. 59) Diagnosis: Shell, white, oval-conic with subturreted spire. Mature whorls, 5, and suture, undulate. Ribs, narrow, raised with scarcely spiral striae; about 9 ribs on the penultimate whorl. Aperture, semicircular and outer lip, variced. It looks like Rissoina scalariformis Schwartz but this shell has a strong nodular basal fold and lacks the apparent spiral threads. Distribution: On beach of Lutao, Taiwan. Dimension: 4.8 x 2.2 rnrn (holotype); 5.0 x 2.2 mm (paratype). Remarks: Rissolina sp. C been reported in Chang (1998). Laseron (1956) treated this shell as cardinalis (Brazier), variation but here a new name is given for their form is markedly different. Moreover, this species has a broad anterior end while the cardinalis has an oblique, deep anterior canal. The name of this species is for Laseron's contribution to this species. Inventory: MLS -RI000059

Key to Species of Genus Rissolina at Lutao, Taiwan Anterior canal, broad and shallow ................................................................................................... 2 Anterior canal, deep and oblique .....................................................................................................8 Basal spiral fold forming large nodule near aperture ...................................................................... 3 Basal spiral fold not forming large nodule ...................................................................................... 4 Sutures, distinct ...................................................................................................................costulata Sutures, indistinct ................................................................................................................... humpa Spire, subturreted; ribs, raised ........................................................................................................ 5 Oval; ribs, low and broad ......................................................................................................... ovalis Basal fold, beaded ........................................................................................................................... 6 Basal fold, nearly smooth .......................................................................................................distant Spire, elevated; ribs not overhanging suture ................................................................................... 7 Spire, conic; ribs overhanging suture ................................................................................... laseroni Shell, stout; aperture, semicircular ......................................................................................... plicata Shell, slender; aperture, lenticulate ..................................................................................... Jmbriata Aperture, semicircular ..................................................................................................................... 9 Aperture, lenticular ........................................................................................................... scalariana Color, usually white, never dark .................................................................................................... 10 Dark in color; ribs, oblique, parallel .......................................................................... Rissoina sp. A Basal fold, smooth .........................................................................................................................11 Basal fold, nodulous ......................................................................................................................13 Sutures, impressed; apex, not domed ............................................................................................ 12 Sutures, channelled; apex, domed ....................................................................................... praecida


12 13 14 15

Subsutural cord, present ..............................................................................................elegantissima Subsutural cord, absent ....................................................................................................... plicatula Whorls, convex ............................................................................................................................. 14 Whorls, angulate ........................................................................................................................... 15 Less ribs (9 ribs on penultimate whorl) .............................................................................cardinalis More ribs (18 ribs on penultimate whorl) ........................................................................... decapitata Spire, acute with more whorls; aperture, smaller ....................................................................crassa Spire, not acute with less whorls; aperture, larger ............................................................... turricula

I:

60. Phosinella tornatilis (Gould, 1860) (Fig. 60) Synonymy: Rissoina tornatilis Gould, 1 860 Rissoina (Phosinella) tornatilis Gould, 1860 in Cernohousky (1 978) Diagnosis: Shell, small, white with a tall conic spire and protoconch, paucispiral of 2 smooth whorls. Mature whorls, 8-9, flatly convex, biangulate at sutures and suture, narrowly channelled. Reticulate sculpture with nodules at intersections and a basal fold; 4-5 spirals and about 13 axials on the penultimate whorl. Aperture, semicircular; anterior canal, oblique, deep; outer lip, variced and fimbriated. Distribution: Loo Choo, Okinawa is the fatherland. It is also found off Lutao, Taiwan and distributed in West Pacific, intertidal to shallow water. Dimension: 4.8 x 1.6 mm. Reference for Identification: Johnson (1964), pl. 14-5, Lectotype; Cernohousky (1 978), pl. 12-8; Habe (1 96 l), pl. 10-19; Kuroda (197 l), pl. 107-9. Inventory: MLS -RI000060 1. Phosinella bicollaris (Schwartz, 1860) (Fig. 61) Synonymy: Rissoina bicollaris Schwartz, 1860 Diagnosis: Shell, small, white, elongate with apex, blunt and spire, obtuse. Mature whorls, 5-6 flatly convex, subangulate at sutures and suture, channelled, beaded. Reticulate sculpture with nodules at intersections and a strong nodular spiral fold at base; 4 spirals and about 14 axials on penultimate whorl. Aperture, semicircular with anterior canal oblique, deep; outer lip, heavily variced and fimbriated. Distribution: Cuba Id. is the fatherland but it is also found off Lutao, Taiwan. Dimension: 4.4 x 2.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1 960), sp. 50; Weinkauff (1 885), Taf. 10-5. Inventory: MLS -RI000061 62. Phosinella villica (Gould, 1861) (Fig. 62) Synonymy: Rissoina villica Gould, 186 1 Diagnosis: Shell, white, elongate oval-conic with protoconch, paucispiral of 2+ smooth whorls. Mature whorls, 8, flatly convex, angulate at the upper suture and suture, channelled and beaded. Sculpture of coarse axial ribs and spiral cord making the intersections, large nodules; replaced by spiral cords on the lower half of body


whorl; 3-4 spirals and about 14 axials on the penultimate whorl. Aperture, semicircular and outer lip, thicken by a sm 0th varix. Distribution: Loo Choo, Okinawa is the fath rland. It is distributed between Japan and Taiwan. Dimension: 5.8 x 2.5 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Johnson (1964), pl. 45-1,2, Lectotype. Inventory: MLS -RI000062

P

63. Phosinella antoni (Schwartz, 1860) (Fig. 63) Synonymy: Rissoina antoni Schwartz, 1860 Rissoina (Moerchiella) antoni Schwartz, 1860 in Kuroda (1941) Diagnosis: Shell, elongate oval-conic with apex, blunt. Mature whorls 5, slightly convex and suture channelled. Reticulate sculpture replaced by spiral cords on the lower half of body whorl; 4 spirals and about 16 axials on the penultimate whorl. Aperture, semicircular with columella, slightly concave and outer lip, thicken by smooth varix. It looks like Phosinella villica (Gould) but this shell is stouter with less mature whorls and its aperture is broader. Distribution: Java, Indonesia is the fatherland. It was recorded in Taiwan by Kuroda, 1941. Dimension: 5.3 x 2.0 mm. Reference for Identification: Schwartaz (1860), sp. 63; Weinkauff (1885), Taf. 5-8, 9, 10; Kuroda (1941), sp. 181. Inventory: MLS -RI000063 64. Phosinella gemmea (Hedley, 1899) (Fig. 64) Synonymy: Rissoina (Phosinella) gemmea Hedley, 1899 Diagnosis: Shell, small, white, oval-conic with protoconch, of 2+ convex whorls. Mature whorls, 6, slightly convex and suture, impressed. Cancellate sculpture of fine axials and spirals, replaced by spirals at base; about 10 spirals and 30 axials on the penultimate whorl. Aperture, semicircular with broad anterior end; outer lip, variced and fimbriated. Distribution: It occurs in Tropical Central Pacific, intertidal. It is found off Lutao, Taiwan. Dimension: 4.6 x 2.2 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Cernohousky (1978), p. 49. Inventory: MLS -RI000064 65. Phosinella decepta (Laseron, 1956) (Fig. 65) Synonymy: Planapexia decepta Laseron, 1956 Diagnosis: Shell, small, white, solid, broad with the outline of spire, slightly convex and apex, blunt. Mature whorls, 5, slightly convex and suture, lightly impressed. Cancellate sculpture replaced by beaded spirals at base; 5-6 spirals and about 18


axials on the penultimate whorl. Aperture, semicircular and outer lip, thick, variced and fimbriated. It is close to Phosinella gemmea (Hedley) but this shell has coarser sculpture and aperture, with narrower anterior end. Distribution: Curtis Id., Australia is the fatherland. It is found off Lutao, Taiwan. Dimension: 4.2 x 1.8 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 55. Inventory: MLS -RI000065

-__\\_

66. Phosinella allanae (Laseron, 1956) (Fig. 66) Synonymy: Rissoina allanae Laseron, 1956 Phintorene allanae (Laseron, 1950) in Laseron (1 956) Phintoreneproxima Laseron, 1956 in Laseron (1 956) Rissoina (Phosinella) allanae Laseron, 1956 in Ponder (1 984) Diagnosis: Shell white, oval-conic with protoconch of 2 smooth convex whorls. Mature whorls, 5-6. biangulated at sutures and suture, channelled. Reticulate sculpture with nodules at intersections, replaced by spirals at base; 4-5 spirals and about 16 axials on the penultimate whorl. Aperture, semicircular and outer lip, variced and fimbriated. Distribution: Woolgoolga, New South Wales, Australia is the fatherland. It is also found off Lutao, Taiwan. Dimension: 5.5 x 2.4 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1 956), Fig. 44; Ponder (1 984), p. 184. Inventory: MLS -RI000066 67. Phosinella fusca (Gould, 1861) (Fig. 67) Synonymy: Alvania fusca Gould, 186 1 Diagnosis: Shell, small, white with protoconch, papillary. Mature whorls, 6-7, flatly convex and suture, channelled. Coarse reticulate sculpture with nodules at intersection; 4-5 spirals and about 15 axials on the penultimate whorls. Aperture, semicircular and outer lip, variced and fimbriated. Distribution: Hong Kong is the fatherland. It occurs off Lutao, Taiwan and Japan. Dimension: 4.4 x 1.6 mm. Reference for Identification: Johnson (1964), Fig. 12-3, Lectotype; Habe (1961), pl. 1020; Kuroda (1 97 l), pl. 107-8. Inventory: MLS -RI000067 68. Phosinella bellula (A. Adams, 1851) (Fig. 68) Synonymy: Rissoina bellula A. Adams, 185 1 Diagnosis: Shell, small, white, semipellucid with spire, acutely conic and protoconch, paucispiral of 2 smooth whorls. Mature whorls, 7-8, biangulate at sutures and suture, channelled. Reticulate sculpture with nodules at intersections, replaced by spiral cords at the lower body whorl; 4 spirals and about 25 axials on the penultimate


whorl. Aperture, semicircular, produced below. It resembles Phosinella villica (Gould). But this shell has a more acute spire with closer ribs. Distribution: It occurs in the Philippines and it is found off Lutao, Taiwan. Dimension: 5.0 x 1.8 mm. Remarks: This is a new record in Taiwan. Reference for Identification: A. Adams (1 85 l), p.266; Schwartz (1 860), sp. 60; Tryon, 1887. Inventory: MLS -RI000068

\

69. Phosinella tokyoensis (Pilsbry, 1904) (Fig. 69) Synonymy: Rissoa tokyoensis Pilsbry, 1904 Diagnosis: Shell, minute, ivory white, oval-conic with elevated spire and protoconch of 2 smooth convex whorls Mature whorls, 3-4 with the last two whorls, inflated and suture, channelled and beaded. Reticulate sculpture, replaced by the spiral cords at the base; 3-5 spirals and about 14 axials on the penultimate whorl. Aperture, semicircular with columella, concave and outer lip, thick variced and fimbriated. Distribution: It occurs between Japan and Taiwan. Dimension: 3.0 x 1.3 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Pilsbry (1904), pl. IV-40. Inventory: MLS -RI000069

Key to Species of Genus Phosinella Sculpture with basal spiral cord ....................................................................................................... 2 Sculpture without basal spiral cord ................................................................................................. 3 Coarse sculpture with beaded intersections; spire, obtuse ............................................... bicollaris Reticulate sculpture; spire, acute, tall .................................................................................. tornatilis Spiral cords, dominant from middle body whorl ............................................................................. 4 Spiral cords only at base .................................................................................................................. 6 Anterior end, produced .................................................................................................................... 5 Anterior end, broad .................................................................................................................. antoni Spire, acutely conic, sculpture of more axials ........................................................................bellula Spire, elevated; sculpture of less axials .................................................................................... villica Coarser sculpture (20- axials on penultimate whorl) ....................................................................... 7 Weaker, finer sculpture (25+ axials on penultimate whorl) ................................................. gemmea Spire, conic ......................................................................................................................................8 Spire, obtuse ....................................................................................................................................9 Protoconch, larger; anterior end, narrower ............................................................................ allanae Protoconch, smaller; anterior end, broader ................................................................................ fusca Finer sculpture; sutures, narrow ............................................................................................ decepta Coarser sculpture; sutures, broad ..................................................................................... tokyoensis


70. Apataxia cerithiformis (Dunker, 1861) (Fig. 70) Synonymy: Rissoa cerithformis Dunker, 1861 in Schmeltz (1874) Rissoina cerithformis Dunker, 1861 in Tryon (1 887) Rissoina (Phosinella) cerithformis Dunker, 1861 in Kuroda (194 1) Rissoina (Apataxia) cerithformis Dunker, 1861 in Kosuge (1965) Diagnosis: Shell, small, white with light brown band or squarish blocks; oval-conic with protoconch, subpellucid, light brown of 3 smooth whorls. Mature whorls, 7-8 and suture, narrowly channelled and undulate. Spiral grooves making axial ribs squarish nodular effect on body whorl or on the upper whorls for some shells; 15-16 axials and 4-5 spirals on the penultimate whorl. Aperture, small, ovate, oblique; outer lip, lirated inside and weakly variced outside. Distribution: It was reported in Taiwan by Kuroda (1941). It is distributed in West Pacific and Hawaii, intertidal. Dimension: 4.0 x 1.4 mrn. Remarks: 1. Cernohousky (1978) used Rissoina (Phosinella) balteata Pease as a synonym of Apataxia cerithformis (Dunker). But Rissoina (Phosinella) balteata Pease has grooves at base according to Pease (1870, p.72) while A. cerithiformis Dunker does not have basal grooves. Cernohousky's figure (p1.12-7) is A. cerithfcrmis Dunker, but not R. balteata Pease. R. balteata (Maes, 1967) is A. cerithformis (Dunker) too, but not R. balteata Pease; 2. Kay (1979) used Rissoina miltozona Tomlin, 1915 as a synonym of A. cerithformis (Dunker). The below figure is the prototype of R. miltozona Tomlin which has basal grooves. Kay's figure (1979, 29D) is A. cerithformis Dunker which does not have basal grooves. Reference for Identification: Kuroda (1941), sp. 183; Habe (1 961), pl. 10-15; Kosuge (1965), pl. 15-2; Maes (1967), pl. 51; Cernohousky (1 978), p.47 and pl. 12-7; Kay, (1979), p.84 and Fig. 29D; Pease (1 870), p.72; Tomlin (1 91 5), pp. 321-322. Inventory: MLS -RI000070

Rissoina miltozona Tomlin, 19 15, prototype Synonymy of R. balteata Pease

71. Apataxia rosea (Deshayes, 1863) (Fig. 71) Synonymy: Rissoa rosea Deshayes, 1863 Rissoina rosea Deshayes, 1863 in Habe (196 1) Diagnosis: Shell, small, reddish brown, elongate conic with spire, straight-sided and apex, blunt. Mature whorls, 7 and suture, shallow, beaded sculpture of axial ribs,


incised by spiral grooves; about 16 beaded ribs on the penultimate whorl. Aperture, ovate angled above with a shallow, broad canal below. It distinguishes from Apataxia cerithiformis (Dunker) by its color, reddish brown and its irregular nodules in sculpture. Distribution: Reunion is the fatherland. It occurs in Japan and Taiwan. Dimension: 3.6 x 1.4 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Deshayes (1863), pl. XXXIV-29; Habe (1 96 l), pl. 10- 18. Inventory: MLS -RI00007 1 72. Apataxia erecta Laseron, 1956 (Fig. 72) Synonymy: Apataxia eripona Laseron, 1956 in Ponder (1984) Diagnosis: Shell, small, white, oval-conic with protoconch, small, conical of 3 whorls. Mature whorls, 6-7, nearly flat and suture, barely impressed sculpture of straight ribs from suture to suture or to the base incised by spiral striae; about 16 ribs on the penultimate whorl. Aperture, small, ovate with oblique anterior canal. It differentiates from the cerithiformis by its ribs lacking distinct squarish nodular effect and its white color without colored band or squarish blocks as the cerithiformis has. Distribution: Heron Id., Australia is the fatherland. It is also found off Lutao, Taiwan and New Guinea. Dimension: 4.4 x 1.8 mm. Remarks: The fig. 55 on Ponder (1984) is Apataxia erecta Laseron, but not Rissoina (Apataxia) miltozona Tomlin which has basal grooves as above figure. Ponder (1984) using A. erecta Laseron as Synonymy of R. miltozona Tomlin could be a mistake. This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 35; Ponder (1984), Fig. 55. Inventory: MLS -RI000072 73. Zebinella decussata (Montagu, 1803) (Fig. 73) Synonymy: Rissoina decussata Montagu, 1803 Diagnosis: Shell, white or light yellow, oval conic with protoconch of one large convex whorl plus an erected nucleus. Mature whorls, 6, slightly convex and suture, narrowly channelled. Sculpture of fine axials, 30-35 on the penultimate whorl crossed by very fine spiral striae leaving small beads on axials. Aperture, semicircular with outer lip thickened and variced. Distribution: It was fossil in Europe but it is also found off Lutao, Taiwan. Dimension: 5.8x2.4 mm for both light yellow (upper pictures in Fig. 73) and white specimens (lower pictures in Fig. 73). Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1960), sp. 44; Weinkauff (1885), Taf. 4-9, 10, 11; Desjardin (1949), pl. IX- 1 1. Inventory: MLS -RI000073


74. Zebinella sp. (Fig. 74) Diagnosis: It looks like the above Zebinella decussata (Montagu) but having less axials; 20-25 on the penultimate whorl in sculpture and aperture, smaller. Distribution: On beach of Lutao, Taiwan. Dimension: 5.8 x 2.4 mm. Remarks: It is probably a new species. Inventory: MLS -RI000074 75. Zebinella reticulata (Sowerby, 1824) (Fig. 75) Synonymy: Rissoina reticulata Sowerby, 1824 Rissoina (Zebinella) reticulata (Sowerby, 1824) in Cernohousky (1978) Rissoina striata Quoy et Gaimard, 1832 in Cernohousky (1 978) Rissoina grandis Philippi, 1847 in Cernohousky (1 978) Diagnosis: Shell, white, oval-conic with protoconch, paucispiral of 2+ smooth, subpellucid, convex whorls. Mature whorls, 6-7, convex and suture, impressed. Sculpture of numerous fine oblique axials bisecting spiral striae; replaced by spirals on the lower body whorl; about 35 axials on the penultimate whorl. Aperture, semicircular with anterior end, broad; outer lip, thickened and advanced outwards. Distribution: Antillen, Cuba is the fatherland. It is distributed in Jamaica, St. Thomas, New Providence, the Philippines and Mauritius. It is also found off Lutao, Taiwan. Dimension: 7.6 x 3.0 mm. Reference for Identification: Schwartz (1 860), sp. 40; Weinkauff (1 885), Taf. 10-2; Cernohousky (1 978), pl. 12-1. Inventory: MLS -RI000075 76. Zebinella tenuistriata (Pease, 1868) (Fig. 76) Synonymy: Rissoina tenuistriata Pease, 1868 Rissoina (Zebinella) tenuistriata Pease, 1868 in Cernohousky (1 978) Diagnosis: Shell, white elongate oval-conic with protoconch, paucispiral of 2 smooth whorls. Mature whorls, 6, convex, and suture, tight, weakly margined. Sculpture of numerous, thin axials which are fading towards the base, replaced by spiral striae; about 40 axials on the penultimate whorl. Aperture, semicircular, large, nearly vertical with inner lip, heavily calloused; outer lip, thickened; anterior canal, broad and shallow. It resembles Zebinella reticulata (Sowerby) but this shell has subsuture, tight and its outer lip, not so advanced outwards. Distribution: Paumotus Id. is the fatherland. It is found off Lutao, Taiwan and distributed in Tropical Indo- Pacific; intertidal. Dimension: 7.5 x 3.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Maes (1 967), pl. 5L; Cernohousky (1978), pl. 12-3. Inventory: MLS -RI000076


Zebinella inermis (Brazier, 1877) (Fig. 77) Synonymy: Rissoina inermis Brazier, 1877 Zymalata inermis (Brazier, 1877) in Laseron (1956) Diagnosis: Shell, white, elongate oval-conic with protoconch of one smooth, convex whorl plus a tilted smaller whorl. Mature whorls, 6, slightly convex and suture, shallowly, impressed. Sculpture of fine axials, about 55 on the penultimate whorl with weak spiral striae between axials. Aperture, semicircular with outer lip, thickened and variced. It distinguishes from Zebinella tenuistriata (Pease) by (a) its subsutures, neither tight, nor margined, and (b) having finer and more axials in sculpture. Distribution: Darnley Id. in Torres Strait, Australia is the fatherland. It is found off Lutao, Taiwan. Dimension: 7.5 x 3.0 rnrn. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), sp. 79. Inventory: MLS -RI000077

78. Zebinella multicostata (C. B. Adams, 1850) (Fig. 78) Synonymy: Rissoina multicostata C. B. Adams, 1850 Diagnosis: Shell, white, oval-conic with apex, blunt. Mature whorls, 6, slightly convex and suture, slightly impressed. Sculptured of fine flexous axials, about 30 on the penultimate whorl, crossed by very fine spiral straie. Aperture, nearly vertical with narrow anterior canal and posterior canal angled above, inner lip, calloused and outer lip, thickened. It has less axials than Zebinella inermis (Brazier) and its aperture, narrower, sinuous at both ends. Distribution: Antillen, Cuba is the fatherland. It is distributed in Jamaica, St. Thomas, Caribbean Sea but it is also found off Lutao, Taiwan. Dimension: 6.6 x 2.4 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1860), sp. 48; Weinkauff (1 885), Taf. 10-4; Desjardin (1949), pl. IX-1. Inventory: MLS -RI000078 79. Zebinella loueli (Deshayes, 1856) (Fig. 79) Synonymy: Rissoina loueli Deshayes, 1856 Diagnosis: Shell, white with protoconch, erected of 3 smooth convex whorls. Mature whorls, 6-7 and suture, narrowly channelled. Fine axials, overriding numerous spiral striae about 40 axials and 12-14 spirals on the penultimate whorl. Aperture, lenticular and outer lip, variced, This shell looks like Zebinella decussata (Mongatu) but this shell has a taller protoconch and a lenticulate aperture with narrow anterior canal. Distribution: It was fossil in Europe but its recent is found off Lutao, Taiwan. Dimension: 5.8 x 2.4 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1860), sp. 45.


Inventory: MLS -RI000079

Key to Species of Genus Zebinella 1 2

3 4

5 6

Suture, narrowly channeled ............................................................................................................. 2 Suture, not channeled ...................................................................................................................... 4 Aperture, semicircular with broader anterior end ............................................................................ 3 Aperture, lenticular with narrower anterior end ....................................................................... loueli Axials, more and beaded; aperture, larger .......................................................................... decussata Axials, less and aperture, smaller ................................................................................. Zebinella sp. Aperture, semicircular ..................................................................................................................... 5 Aperture, lenticular ........................................................................................................ multicostata Suture, neither tight nor margined ................................................................................................... 6 Sutures, tight and weakly margined ................................................................................ tenuistriata Protoconch of 1+ whorls and outer lip, not expanded outwards ...........................................inermis Protoconch of 3 whorls and outer lip, expanded outwards ................................................. reticulate

80. Zebina tridentata (Michaud, 1830) (Fig. 80) Synonymy: Rissoa tridentata Michaud, 1830 Rissoina crassilabrum Garrett, 1857 in Cernohousky (1978) Rissoina tridentata Michaud, 1830 in Schwartz (1860) Zebina (Zebina) tridentata Michaud, 1830 in Ponder (1956) Diagnosis: Shell, white, smooth, glossy, oval-conic with apex, blunt. Mature whorls, 5, flat with body whorl, large, bulging and suture, indistinct. Aperture, semicircular; inner lip, calloused; outer lip, thickened with 3 denticles inside. Distribution: Red Sea is the fatherland. It was reported in Taiwan by Kuroda, 1941 and it is distributed in Tropical West Pacific. Dimension: 8.8 x 5.0 rnrn. Reference for Identification: ~chwartz(1860), sp. 74; Kuroda (1941), sp. 179; Cernohousky (1978), pl. 12-12; Kay (1979), Fig. 295; Ponder (1984), p. 185. Inventory: MLS -RI000080 81. Zebina bidentata (Philippi, 1845) (Fig. 81) Synonymy: Rissoina bidentata Philippi, 1845 Diagnosis: Shell, white, smooth, shining oval-conic with elevated spire and outline, moderately convex. Apex, blunt and mature whorls, 5, nearly flat; suture, barely visible Aperture, ovate with columella, concave; outer lip, expanded outwards anteriorly and variced with a couple of denticles inside anteriorly. Distribution: Mauritius Is. is the fatherland. It is found off Lutao, Taiwan and distributed in West Pacific. Dimension: 6.0 x 2.6 mm. Reference for Identification: Schwartz (1860), sp. 75; Weinkauff (1885), Taf. 13- 1 Inventory: MLS -RI00008 1


82. Zebina browniana (Orbigny, 1853) (Fig. 82) Synonymy: Rissoina browniana Orbigny, 1853 Zebina (Zebina) browniana (Orbigny, 1853) in Ponder (1 984) Diagnosis: Shell, small, brownish white, oval-conic with convex outline and protoconch, paucispiral of 2 smooth whorls. Mature whorls, 6, flatly convex and suture, barely visible. Shell, smooth but obscurely visible ribs appeared on the earlier 2 to 3 whorls for some shells. Aperture, ovate and outer lip, somewhat flared and thickly variced with 2 denticles inside outer lip. It distinguishes from Zebina bidentata (Philippi) by its conic spire of convex outline and its brownish white color whereas the bidentata has an elevated spire and is colored in white. Distribution: St. Thomas is the fatherland. It is distributed in Cuba, Jamaica, Haiti, Martinique, New Zealand, Australia. It is also found off Lutao, Taiwan. Dimension: 4.6 x 1.8 rnrn. Remarks: This is a new record in Taiwan. Reference for Identification: Schwartz (1860), sp. 78; Ponder (1984), p. 185; Thiele (1 929-1 935), Fig. 143; Desjardin (1 949), pl. X-4. Inventory: MLS -RI000082 83. Zebina isolata Laseron, 1956 (Fig. 83) Diagnosis: Shell, white shining, translucent, elongate oval-conic with protoconch, paucispiral of 2 smooth whorls. Mature whorls, 6, nearly flat and suture, linear; body whorl curving in sharply to the base. Surface, smooth and polished. Aperture, short, ovate; inner lip, calloused and outer lip, variced. It is distinguished from Zebina bidentata (Philippi) by its conic spire and shorter aperture without denticles inside while the bidentata has an elevated spire and longer aperture with a couple denticles within. Distribution: Christmas Id., Australia is the fatherland. It is found off Lutao, Taiwan. Dimension: 8.0 x 3.5 mrn. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 122. Inventory: MLS -RI000083 84. Zebina vitrea (Laseron, 1956) (Fig. 84) Synonymy: Lucidestea vitrea Laseron, 1956 Diagnosis: Shell, small, white, smooth, globose with conic spire and protoconch, a small nucleus followed by a larger short whorl. Mature whorls, 4, convex and suture, linear, impressed. Aperture, ovate, angled above with inner lip, calloused and outer lip, thick without denticle inside. Comparing with Zebina tridentata (Michaud), this shell has globose outline and lacks denticles inside outer lip. Distribution: It occurs in Northern Australia. It is also found off Lutao, Taiwan. Dimension: 3.4 x 2.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 169. Inventory: MLS -RI000084


85. Zebina rustica (Watson, 1886) (Fig. 85) Diagnosis: Shell, white, glossy, smooth but with obscurely visible ribs on earlier whorls and apex, blunt. Mature whorls, 4, flat for spire whorls but greatly inflated at the middle of body whorl. Aperture, semicircular; outer lip, variced. Comparing with the tridentata, this shell is much more inflated at the middle of body whorl without denticles inside the outer lip. Distribution: Off Brasil is the fatherland but it is also found on the beach of Lutao, Taiwan. Dimension: 6.0 x 3.5 mm. Remarks: Zebina sp. A been reported in Chang (1 998). This is a new record in Taiwan. Reference for Identification: Watson (1 886), pl. XLIV-11. Inventory: MLS -RI000085 86. Zebina sp. (Fig. 86) Diagnosis: Shell, small, solid, grayish white, smooth, oval with apex lowly domed. Mature whorls, 3 and suture, indistinct with the body whorl, large, taller than a half length of the shell. Aperture, semiovate with columella, oblique, straight; posterior canal, angled above and outer lip, thickened. Distribution: On beach of Lutao, Taiwan. Dimension: 4.2 x 2.2 mm. Remark: Zebina sp. B been reported in Chang (1998). This species is probably a new species. Inventory: MLS -RI000086 87. Zebina elata (Bucquoy, Dautzenberg et Dollfus, 1886) (Fig. 87) Diagnosis: Shell, solid, white, smooth, cylindrical with apex, lowly domed. Mature whorls, 4, slightly convex and suture. indistinct. Aperture, small, ovate, angled above and outer lip, thickened. Distribution: Mediterranean Sea is the fatherland but it is found at the beach of Lutao, Taiwan. Dimension: 6.0 x 2.8 rnrn. Remarks: Zebina sp. C in Chang (1998). This is a new record in Taiwan. Reference for Identification: Bucquoy, Dautzenberg et Dollfus (1 886), Planche 37-1 8. Inventory: MLS -RI000087 88. Zebina nitens Laseron, 1956 (Fig. 88) Diagnosis: Shell, white, smooth, glossy, elongate oval-conic with apex, blunt. Mature whorls, 5, nearly flat and suture, barely visible with the body whorl, slightly inflated, about a half length of the shell. Aperture, lenticulate, not calloused on inner lip and outer lip variced without denticle inside. It looks like Zebina bidentata (Philippi) but this shell has a lenticular aperture without denticles inside of outer lip and lacks callus on inner lip. Distribution: Michaellmas Cay, Australia is the fatherland. It is found off Lutao, Taiwan.


Dimension: 5.8 x 2.5 mm Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1 956), Figs. 119, 120. Inventory: MLS -RI000088 89. Zebina affinis (Garrett, 1873) (Fig. 89) Synonymy: Rissoina affinis Garrett, 1873 Diagnosis: Shell, elongate-oblong, rather solid, smooth, shining, white; spire moderately elevated and apex, blunt. Mature whorls, 7, slightly convex and suture, linear. Aperture large, lenticulate, about one-third the length of the shell. Peristome, very thick, dilated, sinuous above and below; columella and parietal region, heavily calloused. It distinguishes from Zebina bidentata (Philippi) by its aperture, lenticular, heavily variced and lacking denticles inside outer lip. Distribution: It is distributed in Central Pacific; intertidal to shallow water on reefs. It is found off Lutao, Taiwan. Dimension: 6.0 x 2.6 rnrn. Remarks: This is a new record in Taiwan. Reference for Identification: Garre11 (1 873), pl. 2-10. Inventory: MLS -RI000089 90. Zebina injlata Laseron, 1956 (Fig. 90) Diagnosis: Shell, white, smooth, translucent, elongate oval-conic with apex, blunt. Mature whorls, 6, moderately inflated and suture, linear. Aperture, semicircular and outer lip, weakly variced and expanded outwards anteriorly. This is the most elongate shell among Zebina shells. Distribution: Rocky Is., Australia is the fatherland. It is also found off Lutao, Taiwan. Dimension: 8.6 x 3.6 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1 956), Figs. 127,128. Inventory: MLS -RI000090 91. Zebina imbricata (Gould, 1861) (Fig. 91) Synonymy: Rissoina imbricata Gould, 1861 Diagnosis: This shell is close to Zebina nitens Laseron but this shell is broader with inner lip, calloused and some microscopically spiral striae at the bottom near the aperture. It is distinguished from Zebina bidentata (Philippi) by (a) lacking a couple of denticles inside, and (b) outer lip, not advanced outwards anteriorly as the bidentata does. Distribution: Bonin Id., Ryukyu is the fatherland. It is distributed in China Sea and found off Lutao, Taiwan. Dimension: 7.0 x 3.0 mm. Remarks: Kosuge (1965) used some other shell having a much larger aperture and apparent incised spirals as Rissoina imbricata Gould, giving a new genus name,


Sulcorissoina for his shell. Cernohousky (1978) followed. Both the holotype of Rissoina imbricata ould and Kosuge's shell are shown as follows for comparison. Reference for Identific tion: Johnson (1964), pl. 25-4, holotype. Inventory: MLS -~1006091

9

Rissoina imbriata Gould, 1861 7 x 3 mm, holotype

Sulcorissoina imbricata (Gould) after Kosuge (1965)

Key to Species of Genus Zebina at Lutao, Taiwan Columella without anterior nodule .................................................................................................. 2 Columella with anterior nodule ....................................................................................................... 9 Outer lip with denticles inside .........................................................................................................3 Outer lip, smooth inside ..................................................................................................................5 2 denticles inside lip ........................................................................................................................4 3 denticles inside lip ........................................................................................................... tridentata Spire, elevated; anterior end, broader ................................................................................ bidentata Spire, conical; anterior end, narrower ..............................................................................browniana Spire, conical ................................................................................................................................... 6 Spire, elevated ................................................................................................................................8 Body whorl, very inflated ........................:....................................................................................... 7 Body whorl, nearly flat, curving to the base ............................................................................isolata Spire, straight sided ................................................................................................................ rustica Spire of convex whorls and concave suture .............................................................................vitrea Aperture, semiovate, larger ..............................................................................................Zebina sp. Aperture, ovate, smaller ............................................................................................................. elata Inner lip, calloused ........................................................................................................................ 10 Inner lip, not calloused .............................................................................................................nitens Peristoma, weakly variced .............................................................................................................11 Peristoma, heavily variced .......................................................................................................affinis Shell with elevated spire and outer lip, expanded ...................................................................i n f t Shell with conic spire and outer lip, not expanded .............................................................imbricata

92. Moerchiella orbignyi (A. Adams, 1851) (Fig. 92) Synonymy: Rissoina orbignyi A. Adams, 1851


Diagnosis: Shell, moderately large, white, cylindrical with earlier spire, conic. Mature whorls, 7-8, flatly convex and suture, narrow, deep. Surface, smooth but ribbed on earlier 3-4 whorls. Aperture semicircular with posterior canal, acutely angled; inner lip, heavily calloused; o u t e r 3 h i c k e n e d . This species resembles Moerchiella spirata (Sowerby), but M spirata is not so elongate as this species. Distribution: It distributed from the Gulf of Suez to Luzon Id., the Philippines and Lutao, Taiwan. Dimension: 16.0 x 5.0 mm. Remarks: This is a new record in Taiwan. Reference for Identification: A. Adams (1851), p. 265; Schwartz (1860), sp. 64. Inventory: MLS -RI000092 93. Moerchiella persista Laseron, 1956 (Fig. 93) Diagnosis: Shell, white, subtranslucent, elongate oval-conic with spire, subturreted and protoconch, small, convex of 1+ whorl; Mature whorls, 7, slightly convex, angulate at upper suture and suture, channelled and beaded. Surface, smooth on body whorl, very weakly ribbed on the penultimate whorl and ribbed on the earlier 5 whorls, 1520 ribs to the whorl. Aperture, ovate, angled above and outer margin, weakly variced. Distribution: Thursday Id. is the fatherland. It is found off Lutao, Taiwan. Dimension: 7.1 x 2.3 mm. Remarks: This is a new record in Taiwan. Reference for Identification: Laseron (1956), Fig. 67. Inventory: MLS -RI000093 94. Moerchiella artensis (Montrouzier, 1872) (Fig. 94) Synonymy: Rissoina artensis Montrouzier, 1872 Diagnosis: Shell, white, elongate with protoconch of one convex smooth whorl plus a raised nucleus. Mature whorls, 6, slightly convex and suture, impressed, distinct. Surface, smooth for the last 2-3 whorls and ribbed for the earlier 3-4 whorls; about 16 ribs on each whorl. Aperture, semicircular and outer lip, expanded and lightly variced. Distribution: New Caledonia is the fatherland. It occurs in N. Australia and also in Taiwan. Dimension: 8.6 x 2.6 rnrn. Remarks: This is a new record in Taiwan. Reference for Identification: Weinkauff (l885), Taf. 14-3,4; Laseron (1956), Fig. 66. Inventory: MLS -RI000094 95. Moerchiella semiplicata (Pease, 1862) (Fig. 95) Synonymy: Rissoina semiplicata Pease, 1862 Diagnosis: Shell, white, translucent with conical, subturreted spire and protoconch of one smooth, convex whorl plus a raised nucleus. Mature whorls, 6, slightly convex, angulate at the upper suture. The earlier three whorl are ribbed, 12-16 ribs to the whorl; the latter whorls, nearly smooth. Aperture, semicircular with inner lip,


Fig. 1. Rissoa demessa Tate et May, 1901. Left: Dorsal view; Right: Aperture view.

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cFig. 2. Rissoa discrepans Tate et May, 1901. Left: Dorsal view; Right: Aperture view.


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Sulcorissoina imbricata (Gould 44 S ncera (Assiminea) castanea okoyama, 193 1 55 d n c e r a nitida (Pease, 1865) 55

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taiwanensis 56 taiwanica 24 tenuistriata 40 Tharcharia mirabilis Angas 22 thatcheria 24 tibicen 24 tokyoensis 35 tornatilis 35 Tornidae 60 Tornus Jeffreys 1867 60 Tornusplanus (A. Adams, 1850) 60 tridentate 42 44 Truncatella (tahetia)pfei eri von Martens, 1 877 57 Truncatella amaniensrs uroda et Habe, 1961 58,128 Truncatella guerinii A: et J. Villa in Pfeiffer, 1846 59,129 Truncatellajaponica Pllsb et Hirase, 1 9 1 0 57 Truncatella krusiuensis ~ i l % r 1901 ~, 57

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Dl undulate 48

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59 56 35 44


R Zebina 4, 7,43,44 Zebina Zebina browniana Orbigny, 1853) 41 Zebina Zebina tridentata ichaud, 1830 40 Zebina a znis (Garrett, 1873 43,113 Zebina zdentata (Phili pi, 1 455 40,41,42,43,109 Zebina browniana (Or 1 ny, 18 3) 41,109 Zebina elata Bucquoy, dautzenbeq et Dollfus, 1886) 42,112 Zebina H . et . Adams, 1854 6 Zebina imbricata (Gould 1861) 43,114 Zebina inflata Laseron, I956 43,113 Zebina isolata Laseron, 1956 41,110 Zebina nitens Laseron, 1956 42,43 112 Zebina rustica (Watson, 1886) 42, f 11 Zebina sp. 42,44,111 2ebinasp.A 42 Zebina tridentata (Michaud, 1830 6,8,40,41,108 Zebina vitrea Laseron, 1956) 4 ,110 Zebinella 4, 40 Zebinella decussata (Monta u 1803) 6,8,37,38,39,105 Zebinella inermis (Brazier, f8'r 39 107 Zebinella loueli (Deshayes, 1 8 5 3 3d, 108 Zebinella Moerch, 1876 6 Zebinella multicostata (C. B. Adams, 1850 39,107 Zebinella reticulata (Sowerby, 1824) 38, 06 Zebinella sp. 38, 40,105 Zebinella tenuistriata (Pease, 1868) 38,39,106

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The Taiwan Mollusks  

The Taiwan Mollusks-The Rissoacea (Mollusca:Mesogastropoda) from Lutao, Taitung. g. One hundred and thirty-two species of Superfamily Rissoa...

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