''Sphaerium lacustre'', also known as lake fingernail clam, is
species of small
freshwater clam
Freshwater bivalves are one kind of freshwater mollusc, along with freshwater snails. They are bivalves that live in fresh water as opposed to salt water, which is the main habitat type for bivalves.
The majority of species of bivalve molluscs l ...
, an
aquatic bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bival ...
mollusc
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...
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
* Belgium
*
Czech Republic – in Bohemia, in Moravia,
[ Horsák M., Juřičková L., Beran L., Čejka T. & Dvořák L. (2010). "Komentovaný seznam měkkýšů zjištěných ve volné přírodě České a Slovenské republiky. nnotated list of mollusc species recorded outdoors in the Czech and Slovak Republics. '' Malacologica Bohemoslovaca'', Suppl. 1: 1-37]
PDF
near threatened (NT)
*
Slovakia
* Germany – (''Arten der Vorwarnliste'')
*
Great Britain
*
Ireland
*
Nordic countries
The Nordic countries (also known as the Nordics or ''Norden''; literal translation, lit. 'the North') are a geographical and cultural region in Northern Europe and the Atlantic Ocean, North Atlantic. It includes the sovereign states of Denmar ...
: Denmark, Finland, Sweden (but not in Faroes nor in Iceland)
References
External links
''Musculium lacustre''at
Animalbase taxonomy,short description, biology,status (threats), images
Sphaeriidae
Molluscs described in 1774
Taxa named by Otto Friedrich Müller
{{Sphaeriidae-stub