Aquatic invertebrates in Suffolk

35 AQUATIC I N V E R T E B R A T E S IN S U F F O L K Recent Records for: Cladocera - water fleas Ephemeroptera - mayflies Hemiptera Heteroptera water-bugs Hirudinea - leeches A. K. CHALKLEY In Transactions 30 (1994) I summarized all the Suffolk records of species from the above groups that I was able to locate. Those records were, with very few exceptions, either culled from the SNS archives or had been made by myself.

In the two seasons since then I have made many more records and a few more have been sent in as a result of SNS members reading the article. In addition, thanks to the generous Cooperation of the NRA, a large number of new records have been added to our database. Thus in this article over 820 new site records are summarized.

The data from the NRA Covers the period from 1990 to 1994 and is from all the major rivers in the North West and North East of the county. Additional data from the NRA for the southern rivers of Suffolk has now been obtained, although this will take some time to translate into a form that my Computer database can evaluate. We should then have a county wide picture of the status of these groups to report in a future volume of the Transactions.

With some 820 species records covering 113 sites it is necessary to again encode the details for those sites. Thus for each species recorded below the number indicates the sites at which it has been recorded, the letters then refer to individual dates. Only the latest date for a species at a particular site has been listed although many, especially the Hirudinea, have been continuously recorded from some sites for a number of years. A key to these details appears at the end of this article together with a map showing the geographical spread of recording sites. Observant readers will notice that site 76 is missing from the numbered key to sites. This was a Cambridgeshire site which crept into my article and removing all records relating to it has left a gap in the numbering.

CLADOCERA Of the 39 species in my original article 16 were only known as archive records from the turn of the Century and none of these has been found recently. The list below shows in brackets the last date on which each has been recorded:Family CHYDORIDAE Mona guttata Sars (1903) Mona quadrangularis Muller (1903) Mona rectangula Sars (1903) Mona tenuicaudis Sars (1904) Alonopsis ambigua Lilljeborg (1904) Pleuroxus aduncus Jurine (1903)

Family DAPHNIIDAE Ceriodaphnia laticaudata Muller (1903) Ceriodaphnia quadrangula Muller (1903) Daphnia atkinsoni Baird (1903) Daphnia cucullata Sars (1920) Daphnia hyalina Leydig (1903) Moina rectirostris Leydig (1904) Scapholeberis aurita Fischer (1904)

Trans. Suffolk Nat. Soc. 32 (1996)

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Suffolk Natural History, Vol. 32

Family MACROTHRICIDAE Ilyocryptus sordidus Lieven (1903) Macrothrix laticornis Jurine (1903)

Family SIDIDAE Diaphanosoma brachyurum Lieven (1903)

In 1994 I reported modern records for 23 species, but of these there are 10 which have not been found at any new sites. These are:- Bosmina longirostris var. cornuta, Alonella excisa, Graptoleberis testudinaria, Leydigia leydigi, Ceriodaphnia megalops, Ceriodaphnia pulchella, Daphnia curvirostris, Daphnia magna, Daphnia pulex and Scapholeberis mucronata forma cornuta.

One new species, Peracantha truncata Muller, has been added to our lists. It has been recorded from two widely separated, typical sites for the species. This is a water flea that creeps over a surface in a precise manner sieving food particles from the algae, etc. growing there (Fryer, 1993). Suitable surfaces are algae such as Cladophora, the stems of emergent plants and the floating leaves of Potamogeton etc., it has a marked preference for well vegetated ponds and I located it by trawling with a plankton net through floating leafed Vegetation at both sites. Peracantha truncata brings the total number of cladocera recorded in Suffolk to 40, out of a British list of 103. All the new records are listed below.

Peracantha truncata: 0.6 mm Grazing on a submerged surface. ponds in Forest Enterprise woodland at Tangham.

Family BOSMINIDAE Bosmina longirostris Muller. Site 8b

Specimenfrom

Family DAPHNIDAE Ceriodaphnia reticulata Jurine. Site 95a Daphnia longispina Muller.

Family CHYDORIDAE Sites 10b 15c 71a 92a 94a Acroperus harpae Baird. Site 15c Daphnia obtusa Kurz. Sites 51 a 92a Alona affinis Leydig. Site 15c Scapholeberis mucronata Muller. Site 15c Chydorus sphaericus Muller. Sites IIb 15c Simocephalus exspinosus Koch. Site 51a Eurycerus lamellatus Muller.

Simocephalus vetulus Muller.

Sites 15c 54a 79b Sites 8b 8e 15c 46e 54a Rhynchotalona rostrata Koch. Site 15c Peracantha truncata Muller. Sites 10b 15c Pleuroxus trigonellus Muller. Sites 8e 9a

Trans. Suffolk Nat. Soc. 32 (1996)

AQUATIC INVERTEBRATES IN SUFFOLK

37

EPHEMEROPTERA Whilst 19 species of mayfly have been previously recorded in Suffolk, there are still five that have not been seen for many years. The list below has the date of each last record in brackets.

Family Heptageniidae Family BAETIDAE Ecdyonurus sp. (1903) Baetis fuscatus Linnaeus, 1761 (1935) Baetis muticus Linnaeus, 1758 (1906) Family LEPTOPHLEBIIDAE Family CAENIDAE Leptophlebia marginata Linnaeus, 1761 Brachycercus harrisella Curtis, 1834 (c. 1900) (1930) Two species reported in the last article have not been recorded since, these are:- Caenis macrura, and Ephemera vulgata. On a more positive note, there are two species, previous not seen since the 1930s, for which there are new records confirming their continued presence in Suffolk; Ephemera danica, and Paraleptophlebia submarginata.

Also there are two additional species which have been recorded from Suffolk for the first time. Baetis vernus, and Caenis robusta. These two new species were both only recorded as larvae. Adults are less often seen with mayflies, unless they are deliberately searched for at the correct time of the year. Caenis robusta is called 'The Angler's Curse' or 'White Midge' and is the largest British Caenis species. Its large hooked claws and sharp pronotal corners easily distinguish it from smaller species. According to the literature (Elliott et al., 1988a) it is classified as a 'sprawler', meaning it is modified to maintain P o s i tion at the top surface of underwater mud, and as a 'collector-gatherer', meaning that it lives by gathering fine detritus from that mud. It overwinters as a larva. Whilst the only record we have is from the Hundred River it also inhabits ponds and so may yet be recorded in other locations in North East Suffolk.

The other new species, Baetis vernus, was found in 17 locations, all in rivers in the East of the county; from the Waveney in the North to Belstead Brook in the South. B. vernus or the 'Medium Olive Dun' overwinters in the egg stage and in suitable summers may give rise to two or even more generations of adults (Elliott et. al., 1988b), which perhaps implies a fluctuating population level. It is an active swimmer, scraping and gathering food from the surfaces of aquatic Vegetation, rocks, etc. This species is interesting in that although it typically inhabits stony, high altitude streams, it is also found in slow-flowing, weedy sections of rivers, which explains its occurrence in the Suffolk rivers mentioned above. However, it has been suggested that the high altitude variant is in reality B. tenax, long regarded as a synonym of B. vernus (Elliott & Humpesch, 1983).

If this is the case then we would obviously have the true B. vernus in Suffolk.

This brings the total Suffolk list up to 21 (16 recently confirmed) from a total British list of 48. All recent records for the Ephemeroptera are shown below:Family BAETIDAE Cloeon dipterum Linnaeus, 1761. 59 sites.

Sites la 4c 5c 6e 7e 12e 13a 14a 15c 16d 19a 20a 22c 23b 25b 26c 27b 28c 31e 32a 34c 38c 45c 46e 49g 51a 53b 54a 55c 57b 58b 59b 60a 61a 62a 69a 70a 71a 72c 73d 76d 77d 78b 79f 82b 85d 86e 87b 88a 90a 92a 93a 94a 95a 96a 99c 101b 107d 108b 109e

Trans. Suffolk Nat. Soc. 32 (1996)

Suffolk Natural History, Vol. 32

38

Caenis luctuosa: A collector-gatherer Ephemeroptera larva from Temple Bridge on the River Lark.

Cloeon simile Eaton, 1870. Site 19d

Baetis rhodami

P i c t e t , 1 8 4 4 . 44 sites.

ld

6f

12e

13b

14a

15c

19f

20e

23a

25d

26b

27d 32a

35c

39b

44b

46e

50e

54a

55b

56d

57b

65e

66a

69d

70a 73e

75a 78f

81b

86d

87a

88b

90d

93a

96c

97c

99c

103b 105c 106c 107d 110a

Baetis scambus E a t o n , 1 8 7 0 . Sites 20c 78c 86a Baetis vernus C u r t i s , 1 8 3 4 . New Record for Suffolk.

Sites 6c

35b

38b

39d

40b

44a

50b

56b

38c

17 Sites.

65a

78a

81a

97b 99a

102b

79d

85a

86b

107c 109b

1 7 5 8 . 24 Sites.

15c 25b 26b 37a 39a 43a 86b 96a 101b 107b 109a

49a

52c 55a

59b 60a

31b 70d

35c 37a 76d 80a

43a 46b 86d 89c

103a 104a 106a

Centroptilum luteolum Sites

13b

19c

46d

M u l l e r , 1 7 7 6 . 13 Sites.

49b

50a

54a

68a

69b

Centroptilum pennulatum Sites

12b

46c

48a

E a t o n , 1 8 7 0 . 5 Sites.

65a 109d

Family CAENIDAE Caenis horaria L i n n a e u s , Sites la 62d

2c 70c

6b 73b

7c 78b

Caenis luctulosa Burmeister, 1839. 34 Sites.

Sites

2b 50b 93a

6d 52c 95a

Caenis robusta

13b 19d 21a 55c 57a 60a 107d 109e Eaton, 1884.

22a 62d

23b 63c

25d 64a

26d 65d

27c 69b

New Record for Suffolk.

Site 49g

Family EPHEMERIDAE Ephemera

danica Muller, 1764. Site 108a.

Family EPHEMERELLIDAE Ephemerella Sites

12b

ignita Poda, 1761. 11 sites 19b

31e

35a

46e

47b

Trans. Suffolk Nat. Soc. 32 (1996)

52b

56a

62c

65b

78c

AQUATIC INVERTEBRATES IN SUFFOLK

39

Family LEPTOPHLEBIIDAE Habrophlebia fusca Curtis, 1834. 8 sites Sites 2a

35a

38a

40a

50c

73a

75b

105b

Paraleptophlebia submarginata Stephens, 1835. Sites 12a 65a 105c HEMIPTERA HETEROPTERA Previously 34 species of aquatic bugs have been recorded in Suffolk; of these there are only three that have not been re-recorded recently. The list below has the date of each last record in brackets.

Family CORIXIDAE (Lesser Water Boatmen) subfamily Corixinae Hesperocorixa moesta Fieber, 1848 (1933) Family HEBRIDAE (Sphagnum Bug) Hebrus ruficeps Thompson, 1871 (1942) Family GERRIDAE (Pond Skaters) subfamily Gerrinae Gerris argentatus Schummel, 1832 (1903) As with the Mayflies, there are also two species of aquatic bugs not seen for many years, for which new records confirm their continued presence in Suffolk.

Both have been previously recorded from only a Single site, Sigara venusta from Bixley in 1897 and Microvelia pygmaea from North Cove in 1933.

The four new sites for S. venusta are quite widely separated and provide an indication that it may still have a firm foothold in Suffolk. It is reported to be rare in South East England with a preference for rivers or small pools (Savage, 1989b).

The record for M. pygmaea is also of great interest as it means that both British species of micro water cricket have now been recorded. These are Microvelia reticulata and M. pygmaea. In my last article I proposed that it was likely that both species do occur but, since M. pygmaea was used as a synonym for M. reticulata at the turn of the Century, it was also possible that both refer to M. reticulata (Savage, 1989a). This question has now been resolved therefore.

The Single new site for M. pygmaea is a long way from its original known location, and I strongly suspect that it is more widespread. This species is probably under recorded due to its small size (1.8 mm) and its habitat on the water surface of ponds. In my experience it is a lot easier to look under the surface film than on top of it for these small insects, unless you set out deliberately to find them. Probably the easiest way to achieve the latter is to sweep as much surface area as possible with a 1 mm meshed net and include algal mats if possible as these are where the insects may hide. The next step is to lower the net into the water again so that any potential catch can escape the sides of the net. Then slowly raise the net again to concentrate the catch at the bottom and transfer the catch to as large a flat tray of water as is practical. By observing the surface film in the tray from an oblique angle, perhaps by laying down on the ground, even small creatures may be seen without the distraction of seeing submerged invertebrates swimming about.

Trans. Suffolk Nat. Soc. 32 (1996)

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Suffolk Natural History, Vol. 32

ÂŁ

Hydrometra stagnorum or Water Measurer: 12 mm. A surface bug found ort still waters amongst Vegetation at the side ofa river. Specimen from the River Box. Three species which were reported in the last article have not been recorded since, these are:- Sigara concinna, Sigara stagnalis, and Mesovelia furcata.

Both the Corixid species are rare in East Anglia, although they may turn up from time to time. Indeed S. stagnalis seemed to be almost becoming a regulär catch for me in the late 1980s. M. furcata has a similar size and habitat requirement to M. pygmaea and the comments in the last paragraph apply equally well.

There are five additional species which have been recorded in Suffolk for the first time; Gerris thoracicus, Heperocorixa linnaei, Sigara lateralis, Sigara scotti and Sigara semistriata. All of these species are described as 'occasional' in South East England, except for S. scotti and S. semistriata which are rare (Savage, 1989b). Three of these species; H. linnaei, S. lateralis and S. semistriata were recorded from multiple locations and all show quite a large distance between the sites, implying that more may yet be found.

Velia caprai or Water Cricket: 8 mm. A surface bug found on the fastest waters ofa river. Specimen from the River Box.

flowing

This brings the total Suffolk list up to 39 (36 recently confirmed) from a total British list of 63. All recent records for the Heteroptera are listed below.

Family CORIXIDAE (Lesser Water Boatmen) subfamily Micronectinae Micronecta poweri Douglas & Scott, 1869. Sites 48a 93a Micronecta scholtzi Fieber, 1847. Sites IIb 46d

Trans. Suffolk Nat. Soc. 32 (1996)

AQUATIC INVERTEBRATES IN SUFFOLK

41

subfamily Cymatiainae Cymatia bonsdorffi Sahiber, 1819. Site 51a Cymatia coleoptrata Fabricus, 1776. Sites 15c 16b 51a 79c 93a subfamily Corixinae Callicorixa praeusta Fieber, 1848. Sites 12c 51a 71a Corixa panzeri Fieber, 1848. Site 15c Corixa punctata Iiiiger, 1807. 14 sites.

Sites ld 5c 7e 17b 31e 46e 51a 54a 58b 64a 71a 79f 103a 108c Hesperocorixa salhbergi Fieber, 1848. 13 sites.

Sites 5c 15b 17b 31e 32a 49d IIb 82a 84a 95a 97a 100a 110b Hesperocorixa linnaei Fieber, 1848. New Record for Suffolk.

Sites 9b 51a 77b Sigara distincta Fieber, 1848. Sites 8c 14a 15c 24a 46e Sigara dorsalis Leach, 1817. 37 sites.

Sites ld 5b 12e 14a 15c 16d 19c 23d 25c 31e 38c 46e 48a 50b 54a 58b 65d 70e 71a 72a 74b 77a 78d 79a 81a 82a 85a 96c 98a 99a 102a 103b 104a 106d 107d 108c 110b Sigara falleni Fieber, 1848. 18 sites.

Sites 7a 16a 22c 25a 34b 39d 46e 48a 50e 51a 54a 68a 69d 71a 79f 89b 93a 107d Sigara fossarum Leach, 1817. Sites 15c 49c 65c 71a 104a Sigara lateralis Leach, 1817. New Record for Suffolk.

Sites 15c 51a 71a 92a Sigara limitata Fieber, 1848. Sites 15c 24a 34a 40b Sigara nigrolineata Fieber, 1848. Sites 15b 17b 28a 70b 92a 108a Sigara scotti Douglas & Scott, 1868. New Record for Suffolk. Site 77d Sigara semistriata Fieber, 1848. New Record for Suffolk. Sites 65e 104a Sigara venusta Douglas & Scott, 1869. Sites 6f 14a 34b 99c Family GERRIDAE (Pond Skaters) subfamily Gerrinae Gerris lacustris Linnaeus, 1758. 10 sites.

Sites 15c 31e 46e 48a 51a 64a 69a 70e 94a 95a Gerris odontogaster Zetterstedt, 1828. Site 46d Gerris thoracicus Schummel, 1832. New Record for Suffolk. Site 15c Family HYDROMETRIDAE (Water Measurers) Hydrometra stagnorum Linnaeus, 1758.

Sites 30b 46c 48a 52a 62a 63a 64a Family NAUCORDIAE (Saucer Bugs) Ilyocoris cimicoides Linnaeus, 1758.

Sites 15d 112a 113a Family NEPIDAE subfamily Nepinae (Water Scorpion) Nepa cinerea Linnaeus, 1758. 12 sites.

Sites 25d 26a 42a 45a 49a 51a 59a 64a 72b 77a lila 112a

Trans. Suffolk Nat. Soc. 32 (1996)

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Suffolk Natural History, Vol. 32

subfamily Ranatrinae (Water Stick Insect) Ranatra linearis Linnaeus, 1758. Sites 46e 112a 113a Family NOTONECTIDAE (Backswimmers or Water Boatmen) Notonecta glauca Linnaeus, 1758 . 28 sites.

Sites ld 10a 15c 22c 32a 38c 39d 44b 46c 49g 51a 57c 60b 61a 71a 72a 74b 75d 79c Bla 87c 92a 94a 95a 106b 107d 108c Notonecta maculata Fabricius, 1794. Sites 25d 64a 70e 71a 91a 92a Notonecta marmorea viridis Delcourt, 1909. Sites 14a 15c Family PLEIDAE Plea leachi McGregor & Kirkaldy, 1899. Sites 10b 15c 31a 46e 92a Family VELIIDAE (Water Crickets) subfamily Microveliinae Microvelia pygmaea Dufour, 1833. Site 95a Microvelia reticulata Burmeister, 1835. Sites 9b IIb 46e subfamily Veliinae Velia caprai Tamanin, 1947. 9 sites.

Sites 3a 15a 18a 30a 36a 46e 47a 99a 106d

Trans. Suffolk Nat. Soc. 32 (1996)

43 HIRUDINEA The leeches are well represented here with over 300 site records, most of which Ihow the species as long established at the site. Whilst there are no new species of the Hirudinea to report, all 10 previously recorded in the county have new sftes listed below, induding Trocheta subviridis, which had no. to ound since 1858 at Dallinghoo Rectory. There are 16 species on the British list The number of sites at which the majority of leech species have been recorded is interesting in itself. None of the surveys has been mounted wi h the particular aim of f.ndmg leeches, nor was there a systematic use of baited traps.

K t a l surveys were designed with the mm of sampling the general aquatic fauna as evenly as possible, so that leeches should be fair y represented amongst the v J o u s Orders. However, from the large number of siteslocated for " o f t h e H i r u d i n e a it is evident that they are very widespread in the county s nver Systems and ponds, helped no doubt by fairly simple habitat requirements for most species.

Glossiphonia complanata: One ofthe world's commonest ^ c h e s j f r ' s h water. Mainly preying on molluscs, this specimenfrom Temple Bridge on the River Lark.

However, there are certain species which are recorded from relativelyfew sites and the reasons for this are not always obvious. The following comments about the less widespread species may be relevant. " " ^ V ^ T t i T , occurs in the stream running through my own garden (site 8) I t i s ^ abundant there but is rarely seen during the day when it is of en to be found ou of water, under stones on the bank, or in a nearby stone wall. DĂźring, the night it emerges to feed, and this is as likely to be out of water as in. Whilst it s v a y easy for me to observe nocturnally in my own garden the general_ surveys reported here are all from the hours of daylight. I conclude therefore tha H sanguisuga is relatively under recorded. Interestingly it is reported E & Mann 1979, p. 51) that this leech will collect under large stones at the water s edge or burrow into bankside soil in the winter. In my own stream they seem to be very active all winter, unless the weather is particularly severe.

I surmise that the records for Erpobdella testacea do not fairly represenUts abundance because it is well adapted to live in eutrophic ponds with a low summer oxygen concentration (Elliott & Mann 1979, p. 52) and it occurs sparsely in rivers. The sites listed here are, in the main, nvers and streams Piscicola geometra is also represented from slightly fewer sites than o her species. This leech is exclusively an ectoparasite of fish. It spends a rather

Trans. Suffolk Nat. Soc. 32 (1996)

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Suffolk Natural History, Vol. 32

greater time on its host than some other species and when satiated will drop off to digest its meal. At this point its high oxygen consumption (Elliott & Mann 1979, p. 33) will limit the number of sites where it will occur to the faster flowing sections of our rivers. The number of recorded sites may well be limited by ease of sampling rather than the abundance of P. geometra.

Trocheta subviridis was previously recorded only once, in 1858 (Morley, 1936). The first British specimen was discovered only eight years previously

by Gray in 1850 in Regents Park, London. Since then it has been reported sporadically from widespread locations in England and Wales. (Elliott & Tullett), 1982) and it is not at all common. One other factor perhaps limiting its discovery is that it becomes largely terrestrial once mature (Hartley, 1962) and is apparently sometimes abundant in sewage effluent Channels when fully aquatic. Perhaps a different ränge of sites needs to be examined for this species?

All the new records for the Hirudinea are now listed:RHYNCHOBDELLAE Family PISCIOLIDAE Piscicola geometra L i n n a e u s , 1758. 27 sites.

Sites 4c 6a 19e 25d 26c 31e 33b 46a 47c 49c 55c 57a 59a 60a 62b 65d 68a 69b 72b 74a 78f 79f 80b 86e 101a 107c 109e Family GLOSSIPHONIIDAE Theromyzoti tessulatum M u l l e r , 1 IIA. 54 sites.

Sites lb 6d 7b 12d 15c 16d 19g 22c 23b 25d 26d 27d 30c 32a 35c 38c 39c 43b 44b 45a 47b 49g 52c 53a 54a 55e 57c 59b 63c 64a 65e 69b 70d 72c 73b 74b 75c 78d 79a 80b 82c 83a 85d 86b 87c 89c 96c 97d 99d 103a 106f 107d 108c 109c Hemiclepsis marginata M u l l e r , 1774. 13 sites.

Sites 19b 20d 27a 62c 69b ,72b 73a 74b 78e 79f 80c 97e 106c Glossiphonia heteroclita L i n n a e u s , 1761. 9 sites.

Sites 4b 7d 15c 16d 37a 57c 80a 85a 99b Glossiphonia complanata L i n n a e u s , 1758. 75 sites. lc 6f 12d 13d 15c 16c 17a 19g 20e 21b 22b 23d 25d 26d 27d 29a 30c 31c 33c 34d 35c 36b 37a 38c 39c 40c 41a 42b 43b 44b 45c 46e 49e 50e 52d 55e 56c 57e 58b 60b 62e 63b 65e 66c 67a 68a 69b 70e 72c 73e 74b 75d 77c 78f 79f 80b 81c 82c 85b 86e 87c 88b 89c 90d 96c 97e 99d 101b 103b 105d 106f 107d 108c 109e 110c Helobdella stagnalis L i n n a e u s , 1758. 67 sites.

Sites lc 4d 5a 6b 7e 12e 13c 15c 16c 20b 22c 23c 25c 26d 28c 30c 33b 34b 35b 38c 39d 40d 43a 44b 46b 49e 50b 51a 53b 55d 57c 58b 59b 65c 66b 67a 69c 70e 72c 73c 74b 75c 77a 78e 79e 80c 81c 82c 83a 85c 86c 88a 89d 96b 97e 98c 99d 101b 102a 103b 104a 105a 106b 107d 108c 109d 110c GNATHOBDELLAE Family HIRUDINIDAE Haemopsis sanguisuga Linnaeus, 1758. Sites 8a 96c

Trans. Suffolk Nat. Soc. 32 (1996)

45

AQUATIC INVERTEBRATES IN SUFFOLK

PHARYNGOBDELLAE Family ERPOBDELLIDAE Erpobdella Sites

19f

testacea 31e

Savigny, 1820. 7 sites.

32a

64a

90d

105b 110a

Erpobdella octoculata Linnaeus, 1758. 75 sites.

Sites ld 3b 25d 26d 45b 46c 62e 63c 85d 86e 106e 107d

4a 27d 47b 65e 87c 108b

6f 28b 49f 69d 88b 109e

7e 30d 50e 70e 89c 110c

12e 3 ld 52c 72c 90c

13d 33a 54a 73e 93a

16d 34d 55e 74b 96c

18b 35c 56d 75d 97e

19g 38c 57c 78e 98b

20e 21c 22c 39c 40d 43b 58a 59b 60a 79e 81c 82c 99b 101b 102a

23d 44b 61b 84a 103b

Trocheta subviridus Dutrochet, 1817. Sites 20a 70a 89a 90b Site Details SITE NAME

OS Ref.

1 2 3 4 5 6

3 Arches Bridge, Thorpeness Meare Bridge Street, Burv, River Lark Raingate Bridge, Bury, R. Linnet Beccles Yacht Station, R. Waveney 2 km W of Beccles, R. Waveney Beversham Bridge, R. Aide

62/462597 52/858644 52/860637 62/421912 62/449909 62/359581

7

Blyford Bridge, R. Blyth

8

Holbrook & Lake, Boxford, R. Box

SITE

9 10 11 12

Skating Pond, Boxford Stoney Down Grove, pond 1, Boxford Stoney Down Grove, pond 2, Boxford Brightwell Bridge, A1093, R. Deben

13 14 15 16 17 18 19

Church Lane, Bruisyard, R. Aide Hold Farm Stream. R. Stour Tangham, 3 Ponds on River Tang Dock Farm Bridge, River Butley Chediston Bridge, R. Blyth Chevington Bridge, R. Linnet Butley Mill, Butley River

20

Watering Farm Bridge, R. Gipping

21 22 23 24 25 2« 27 28 29 30 31

Debenham Bridge, R. Deben Barley Farm, A1120, R. Deben Kentish Town Bridge, R. Deben Elveden Forest, Center Parcs Lakes Abbey Bridge, Eye, R. Dove Eyke Ford, R. Deben Farnham Bridge, R. Aide B113 Road Bridge, R. Deben Buxted Outfall. R. Waveney Fornham All Saints Bridge, R. Lark Beck Bridge, Freckenham, R. Kennet

32 33 34 35

Badlingham Manor Br., R. Kennet St Olaves Bridge, A143, R. Waveney Frostendon Bridge, Eastan Broad Great Bealings Bridge, R. Fynn

DATES

a 08/04/91 a 03/06/93 a 10/07/90 a 23/08/90 a 18/03/91 a 16/08/90 e 18/05/92 62/424765 a 02/07/90 e 27/07/92 52/971405 a 18/08/94 e 26/08/95 52/982416 a 04/09/94 52/982413 a 04/09/94 52/982412 a 04/09/94 a 19/04/90 62/250434 e 10/08/92 a 19/08/91 62/325661 52/923335 a 21/08/94 62/354477 a 31/03/94 a 03/10/90 62/382478 62/359776 a 04/11/91 52/798595 a 01/06/92 62/385517 a 24/05/90 e 16/08/91 62/088564 a 17/05/90 e 06/08/92 62/176628 a 08/05/91 62/201618 a 08/05/91 62/233620 a 25/07/91 52/80-79a 03/09/94 62/152738 a 19/10/90 62/314527 a 21/08/90 a 16/05/91 62/359601 62/065695 a 10/04/90 62/311875 a 16/07/91 52/842678 a 02/07/90 52/662733 a 23/09/91 e 09/08/94 52/679709 a 09/08/94 a 23/08/90 62/456995 a 20/06/90 62/489813 62/234484 a 24/05/90

08/08/91 26/10/93 19/05/93 29/05/91 16/10/91 06/11/90 02/09/92 17/07/91

c 19/05/92 c 05/04/94

d 02/09/92

c 23/07/91 c 23/07/92 c 16/08/91

d 22/09/92

c 04/11/91

d 25/03/92

b 20/08/94

c 08/10/94

d 06/05/95

b b b b

26/08/95 26/08/95 26/08/95 03/08/90

c 24/07/91

d 03/04/92

b 31/10/91

c 19/05/92

d 02/09/92

b b b b b f b

01/06/94 27/03/91 27/07/92 19/05/93 30/08/90 18/05/92 23/10/90

c 18/08/94 c 18/05/92

d 29/07/92

b 14/11/91 b 14/05/92 b 31/10/91

c 14/05/92 c 13/08/92 c 14/05/92

b b b b

c c c c

b b b b b b f b

c 03/10/90 g 29/07/92 c 13/05/91

d 08/11/91

d 27/13/91 d 08/08/91

d 13/08/92

22/05/92 29/10/91 21/10/91 08/09/92

d 10/09/92 d 29/07/92 d 02/09/92

b 30/09/91 b 16/06/93

c 26/10/93 c 01/11/93

d 23/03/94 d 28/03/94

b 30/05/91 b 13/09/90 b 24/10/90

c 23/07/91 c 18/03/91 c 10/08/92

d 27/07/92

14/11/91 08/05/91 16/08/91 01/11/91

Trans. Suffolk Nat. Soc. 32 (1996)

46

Suffolk Natural History, Vol. 32

SITE 36 37 38 39 40 41 42 43 44 45 46

SITE NAME Gt Livermere Rd Bridge, Broadmere Stream Sicklesmere Road Bridge, R. Lark Gedding Corner, R. Rattlesden Rectory St., Haiesworth, R. Blyth Bramfeld Bridge, A144, R. Blyth Fiat Farm Bridge, R. Lark Hawstead Bridge. R. Lark Hengrave Bridge, R. Lark Hollesley Bridge, R. Ore Swan Bridge, Hoxne, R. Waveney Temple Bridge, Icklingham, R. Lark

52/886716 52/877607 62/955578 62/385775 62/390764 52/871582 52/864596 52/83269« 62/351442 62/179771 52/758728

47 48 49

Cavenham Strm, Mill Heath, R. Lark Icklingham Bridge, R. Lark Kessingland Dam, Hundred River

52/773715 52/773724 62/510862

50

Little Bealings Bridge, R. Fynn

62/230476

51 52 53 54 55

Steward's Barn Pond, Leavenheath Lackford Bridge, R. Lark Lovers Lane Bridge, Minsmere River A134 Bridge, Chad Brook Mariesford Bridge, A12, R. Aide

52/957377 52/788711 62/455635 52/876459 62/327577

56

Martlesham Bridge, R. Fynn

62/252473

OS Ref.

DATES a 16/07/90 a 26/10/93 a 17/05/90 a 17/04/91 a 10/05/90 a 03/06/93 a 03/06/93 a 26/10/93 a 03/10/90 a 11/11/91 a 30/09/91 e 24/08/95 a 19/05/92 a 09/08/94 a 20/06/90 e 19/09/91 a 21/08/90 e 10/08/92 a 12/08/94 a 30/09/91 a 08/04/91 a 23/08/94 a 06/11/90 e 02/09/92 a 24/05/90

b 23/03/94 b 12/05/92 b 08/08/91 b 03/07/90

c 13/08/92 c 04/11/91 c 04/10/90

d 27/07/92 d 25/03/92

b b b b b

26/10/93 23/03/94 29/07/92 26/05/92 01/11/93

c 10/09/92 c 23/03/94

d 07/08/95

b 01/11/93

c 23/03/94

b 13/09/90 f 24/03/92 b 24/10/90

c 25/02/91 g 27/07/92 c 10/05/91

d 24/10/91

b 14/06/93 b 02/09/92

c 01/11/93

d 23/03/94

b 16/05/91

c 21/10/91

d 18/05/92

b 16/08/91

c 13/05/92

d 10/08/92

d 17/07/91

This map shows the geographica! spread of the sites listed.

f.

1

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• J

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f

, ! i

1«

\ V

Trans. Suffolk Nat. Soc. 32 (1996)

T t i

T*

O b r ^ \

:

•

9 tf

7

47

AQUATIC INVERTEBRATES IN SUFFOLK

SITE 57 58 59 6« 61 62

SITE NAME Mendham Bridge, R. Waveney Chambers Hill. R. Waveney Judes Ferry, R. Lark Kenny Hill Road Bridge, R. Lark Isleham Weir, R. Lark Lark Hall Farm, Great Fen., R. Lark

63 64 65

Moulton Rd Bridge, R. Kennet Moulton Bridge, R. Kennet Waterworks, Newbourne, Mill River

66 67 68 69 70

Newbourn Viilage, Mill River North Cove, R. Waveney Wormingford Bridge, R. Stour Hawkes Mill, R. Gipping Badley Bridge, B113,R. Gipping

71 72 73

Nowton Lodge Farm Pond Billingford Bridge, R. Waveney Burford Bridge, B115, R. Rattlesden

74 75 77 78

Doit Bridge, R. Waveney Palgrave Bridge, R. Waveney Potters Bridge, B1127, Easton Broad EUingham Mill, R. Waveney

79

Locks Lane Foot Bridge, R. Waveney

80 81 82 83 84 85 86

Geldeston Lock, R. Waveney Shottisham Mill, R. Deben Snape Watering, R. Aide Pastures Farm, R. Wang Sotterly Park, Hundred River Hulver Bridge, Hundred River Sproughton Mill, R. Gipping

87 88 89 90 91 92 93 94 95 % 97

Benhall Green Bridge, R. Aide Old Newton Bridge, R. Gipping Station Road Bridge, R. Gipping Gladstone Bridge, R. Gipping Hinstall Forest, Ditches Tunstall Forest, New Pond Sudbury Common Lands, R. Stour Theberton Woods, Pond Theberton Woods, Pond Eastbridge, Minsniere River Blackheath Bridge, R. Blyth

98 99 100 101 102 103 104 105 106

Cat Bridge, Thomdon, R. Dove Buck Inn Bridge, R. Wang Sotherton Bridge, A145, R.Wang Culford Stream, R. Lark Wangford Bridge, R. Wang Hill Farm Bridge, R.Wang Wolsey Bridge, A1095,R. Wang Church Lane Br., Belstead Brook Washbrook Br., Belstead Brook

107

Needham MiU, R. Waveney

OS Ref. 62/269830 62/281837 52/677748 52/697975 52/649761 52/624797

DATES a 16/04/91 a 26/05/92 a 05/05/92 a 01/11/93 a 01/11/93 a 17/06/91 e 28/03/94 52/698641 a 19/05/92 52/697644 a 23/08/94 a 19/04/90 62/270420 e 13/08/92 a 03/10/91 62/273433 62/465912 a 23/02/90 52/933329 a 21/08/94 62/089554 a 31/07/90 a 17/05/90 62/080559 e 18/08/92 a 23/08/94 52/868612 a 10/10/90 62/168783 62/027586 a 17/05/90 e 06/05/92 62/089800 a 16/04/91 62/121782 a 25/03/91 a 05/07/90 62/509791 a 05/10/90 62/364916 e 26/05/92 e 05/07/90 62/389906 e 04/03/92 a 29/05/91 62/390908 a 03/10/90 62/316445 a 29/08/91 62/383599 a 27/09/90 62/414789 a 27/07/92 62/453850 62/466874 a 12/09/90 a 10/08/90 62/125451 e 06/08/92 a 16/05/91 62/387611 62/045604 a 01/11/91 62/051588 a 16/03/90 62/047603 a 23/10/90 62/409526 a 02/10/94 62/413526 a 02/10/94 52/86-42a 01/06/94 62/420656 a 02/10/94 62/421654 a 02/10/94 62/453664 a 08/11/91 62/433746 a 12/03/90 e 27/07/92 62/138707 a 10/04/90 62/447799 a 02/10/91 62/443797 a 14/10/91 a 19/04/90 52/820706 a 02/10/91 62/463791 a 02/10/91 62/461779 a 02/10/91 62/471768 a 21/02/91 62/108426 a 17/05/90 62/120421 e 06/05/92 a 17/04/90 62/229812

26/09/91 08/09/92 01/11/93 28/03/94 28/03/94 24/08/92

c 08/09/92

b 16/06/93

c 01/11/93

b 30/08/90

c 24/10/90

b 03/04/92

c 10/08/92

b 06/08/91 b 22/10/90

c 05/05/92 c 15/05/91

d 06/08/92 d 17/10/91

b 26/05/92 b 15/10/91

c 10/09/92 c 06/08/91

d 18/09/91

c 18/09/91 c 08/04/92 c 29/07/91

d 08/09/92 d 27/07/92 d 04/10/91

c 20/03/91

d 24/06/91

b b b b b b

b b b b f b f b b b

08/09/92 19/06/91 05/10/90 15/04/91 10/09/92 29/10/90 23/07/92 23/07/91 05/05/92 29/10/91

c 16/06/93

d 01/11/93

d 03/10/91

c 02/06/92 c 29/07/92 c 02/09/92

d 27/07/92 d 12705/92

b 15/07/91 b 08/08/91

c 19/09/91 c 08/10/91

b b b b

21/10/91 13/08/92 18/09/91 06/08/91

c 02/09/92 c 13/08/92 c 18/10/91

d 13/08/92

b 18/05/92 b 03/07/90

c 02/09/92 c 17/07/91

d 08/04/92

b 08/05/91 b 10/04/92

c 10/09/92 c 29/07/92

d 25/09/92

c 10/10/91 c 18/06/91

d 06/08/92 d 10/10/91

c 08/07/91

d 08/09/92

b 01/11/93 b 29/07/92 b b f b

18/06/91 22/10/90 06/08/92 20/03/91

Trans. Suffolk Nat. Soc. 32 (1996)

48 SITE 108 109

110 111 112 113

Suffolk Natural History, Vol. 32 SITE NAME Weybread Bridge, R. Waveney Glevering Bridge, Wickhain Market, R. Deben

OS Ref.

DATES

62/229812

a 10/04/90

b 24/10/91

c 08/09/92

62/295566

b 21/08/90

c 29/10/91

A12 Bridge, Yoxford, Minsmere R. Alder Car Farm Haddiscoe Marshes Lound Reservoir

62/399689

a 18/04/90 e 29/07/92 a 24/05/90

b 16/10/91

c 02/09/92

62/095553 62/457984 63/509007

a 01/08/94 a 08/04/95 a 26/08/95

d 13/05/92

Site which refer to records made by myself are as follows:8, 9, 10, 11, 14, 15, 24, 31, 32, 46, 48, 51, 54, 64, 68, 71, 91, 92, 93, 94, 95 Tony Brown supplied the records from sites 112 & 113. Joan Hardingham gave the record for site 111. All other records from the NRA. Acknowledgements I thank Elliott Taylor and Sue Loveridge of the National Rivers Authority for their assistance in supplying past records from their surveys in a suitable form for Computer processing.

The site distribution map has been printed with DMAP Software written by Dr. Alan Morton.

References Cladocera Fryer, G. (1993). The Freshwater Crustacea ofYorkshire\ 91. Leeds, Yorkshire Naturalists' Union & Leeds Philosophical & Literary Society.

Ephemeroptera Elliott, J. M. & Humpesch, U. H. (1983). A key to the adults of the British Ephemeroptera.. Ambleside, Freshwater Biol. Assoc. Sei. Publ. No. 47.

Elliott, J. M„ Humpesch, U. H. & Macan, T. T. (1988a & b). Larvae of the British Ephemeroptera. Ambleside, Freshwater Biol. Assoc. Sei Publ No. 49.

Hemiptera Heteroptera Savage, A. A. (1989a & b). Adults of the British aquatic Hemiptera Heteropptera. Ambleside, Freshwater Biol. Assoc. Sei. Publ. No. 50.

Hirudinea Elliott, J. M. & Mann, K . H. (1979). A key to the British freshwater leeches.

Ambleside, Freshwater Biol. Assoc. Sei. Publ. No. 40.

Elliott, J. M. & Tullett, P. A. (1982). A provisional atlas of the freshwater leeches ofthe British Isles. Ambleside Freshwater Biol. Assoc.

Hartley, J. C. (1962). The life history ofTrocheta subviridis Dutrochet. J. Anim Ecol. 31, 519.

A. K. Chalkley, 37 Brook Hall Road, Boxford, Sudbury, Suffolk COIO 5HS E.mail 100776.1221 @ compuserve.com

Trans. Suffolk Nat. Soc. 32 (1996)

49

Ranatra Linearis - In Flight!

I have been recording Ranatra linearis, the Water Stick Insect, for many years; yet have never seen one in flight. The question as to whether this aquatic bug can fly is puzzling. Many references suggest that Ranatra cannot fly, despite having small wings. I myself have never accepted that this is the case nor that the allied species Nepa cinerea is flightless. The Field Guide to Insects by Michael Chinery, for example, states that 'Both species are winged but cannot fly as the flight muscles are poorly developed'. Some other works echo this or simply do not mention flight.

The question has now been answered by a fascinating piece of Observation

by SNS member Joan Hardingham. Whilst working on the strawberry crop at her farm near Needham Market on 7th of June 1996 she saw a specimen of Ranatra linearis fly across the field and land on some black plastic sheeting, presumably mistaking it for the reflective surface of a pond. She reported to me that its wings were of a 'russety' colour and rather like an earwig's. It flew holding its body at an angle of about 60째 to the horizontal and she feit that it resembled a praying mantis in flight. When it took off again it did so vertically, was certainly less ungainly than a cranefly, indeed she described it as quite a strong flier.

The Observation is all the more remarkable if you consider the weather conditions on June 7th. This was one of the hottest days of the year reaching 31째C and the insect was seen flying at 11 am, almost the hottest period of the day. The evening saw quite violent thunderstorms over much of the country at the end of a 72-hour period of falling air pressure. Many other aquatic bugs of course are caught in light traps because they fly at night, when the air is cooler and more moist, but this specimen seemed content in the heat.

Did the impending thunder, the drop in air pressure or the heat trigger it's flight? It is said that Gerris, the pondskaters, overwinter as fully winged forms but the summer population reabsorb their wing muscles, perhaps to increase the available protein for egg production (Gutherie, 1989). Was Joan's specimen dispersing prior to egg laying? Another piece of research (Savage, 1989) suggests there is evidence that temperatures over 24째C may trigger the development of f체ll wing muscles in the Corroxid bug Sigara scotti. Perhaps the high temperatures that week led to it taking flight? As usual in Natural History, the more you find out, the more questions there are to answer. I would very much appreciate any observations members might have on this matter, especially if they have seen Ranatra fly.

References Gutherie, M., (1989). Animals of the surface film-, 24. Naturalist's Handbooks No. 12. Richmond Publishing Co. Ltd., Slough.

Savage, A. A., (1989). Adults of the British Aquatic Hemiptera Heteroptera\ 153. Scientific Publication No. 50. Freshwater Biological Association, Ambleside.

A. K. Chalkley

Trans. Suffolk Nat. Soc. 32 (1996)