Subclass Heterodonta Suborder Sphaeriacea Rank Species | Order Veneroida Higher classification Pisidium | |
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Similar Pisidium, Molluscs, Pisidium subtruncatum, Bivalvia, Sphaeriidae | ||
Pisidium casertanum, the pea cockle or pea clam, is a minute freshwater bivalve mollusc of the family Sphaeriidae.
Contents
Description
The shell is broad, sub-triangular or oval and is ornamented with sculpture of faint concentric striations.The umbos are slightly behind the middle.The Periostracum is silky, scarcely glossy. In colour it is whitish to grey-brown and often the shell is coated with reddish-brown deposits.
The shell is of similar shape to Sphaerium novaezelandiae but is smaller as an adult, more inflated, with a deeper hinge-plate, stronger teeth, and the ligament is not visible externally.
Length is up to 4.5 mm, height 3.7 mm, and thickness 2.3 mm.
Distribution
It has a cosmopolitan distribution and is perhaps the world's widely distributed non-marine mollusc.
References
Pisidium casertanum Wikipedia(Text) CC BY-SA