Sphaerium lacustre explained

Sphaerium lacustre, also known as lake fingernail clam, is species of small freshwater clam, an aquatic bivalve mollusc in the family Sphaeriidae, the fingernail clams and pea clams.

Description

The 8–11 mm. shell is oval to quadrangular in shape. The umbos which are capped by the juvenile shell are slightly in front of middle directed forwards. The posterior end is broad and truncated. The shell is fragile, fairly glossy and pearl grey to white in colour. The periostracum (surface) is ornamented with fine, even, concentric striation.

Distribution

The native distribution of this species is Holarctic and occurs in islands and countries including:

• Algeria^[1]
• Belgium
• Czech Republic – in Bohemia, in Moravia,^[2] near threatened (NT)^[3]
• Slovakia^[2]
• Germany – (Arten der Vorwarnliste)^[4]
• Great Britain
• Ireland
• Nordic countries: Denmark, Finland, Sweden (but not in Faroes nor in Iceland)

External links

• Musculium lacustre at Animalbase taxonomy,short description, biology,status (threats), images

Notes and References

1. Ramdini Ramdane, Dirk Van Damme, Sadouk Ghania & Medjdoub-Bensaad Ferroudja (2020). "Rediscovery of Armiger crista (Linnaeus, 1857) (Gastropoda Planorbidae) in Algeria". Biodiversity Journal 11(4): 821–824.
2. Horsák M., Juřičková L., Beran L., Čejka T. & Dvořák L. (2010). "Komentovaný seznam měkkýšů zjištěných ve volné přírodě České a Slovenské republiky. [Annotated list of mollusc species recorded outdoors in the Czech and Slovak Republics]". Malacologica Bohemoslovaca, Suppl. 1: 1-37. PDF.
3. Red List of the molluscs (Mollusca) of the Czech Republic http://mollusca.sav.sk/malacology/redlist.htm
4. Glöer P. & Meier-Brook C. (2003) Süsswassermollusken. DJN, pp. 134, page 109,