Identification

[paul monfils]

This appears to be a Lioconcha, in the family Veneridae.  There are several species with rather similar markings, which are also extremely variable within each species, so species ID can be difficult.  I think this may be L. castrensis, in spite of the rather sparse markings, because most of the other species are a bit more elongate than this shell, and most of them do not usually reach the size of this shell.

http://www.conchology.be/?t=66&family=VE...castrensis
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