Pisidium conventus explained

Pisidium conventus, the arctic-alpine pea clam, is a species of freshwater bivalve from the family Sphaeriidae.

Description

The small (2.2–2.8 mm.) shell is oval in shape and thin and fragile. It is broad and flattened (laterally compressed) with flattened umbos near the midpoint. The colour is yellowish-white and the periostracum (surface) is silky with fine, concentric striation.

Ecology

P. conventus is a relict of colder climatic periods found only in deep, cold, upland lakes.

Distribution and conservation status

• Not listed in IUCN red list – not evaluated (NE)^[1]
• Germany – endangered (gefährdet)^[2]
• Poland – vulnerable (VU)^[3]
• Nordic countries: Faroes, Finland, Norway and Sweden (not in Denmark, Iceland)
• Great Britain and Ireland^[4]

External links

• Pisidium conventus at Animalbase taxonomy,short description, biology,status (threats)
• Polish Red Data Book

Notes and References

1. 2006 IUCN Red List of Threatened Species. . Cited 30 May 2007.
2. Glöer P. & Meier-Brook C. (2003) Süsswassermollusken. DJN, pp. 134, page 109,
3. http://www.iop.krakow.pl/pckz/opis.asp?id=124&je=en Pisidium conventus - Polish Red Data Book of Animals
4. Roy Anderson,2005 An annotated list of the non-marine molluscs of Britain and Ireland Journal of Conchology, 38 (6): 607–637, (published 2005)http://www.conchsoc.org/sites/default/files/MolluscWorld/Anderson-2008.pdf.