Emarginula

Emarginula is a genus of small keyhole limpets, marine gastropod molluscs in the family Fissurellidae. The oval shell is obliquely conical with a backward-pointing recurved apex. There is a deep incision in the anterior margin. A distinct anal fasciole extends upwards from this incision. The surface is latticed, sculptured with radial ribs. There ...
Found on http://en.wikipedia.org/wiki/Emarginula
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