Glycymeris nummaria

Glycymeris nummaria is a species of saltwater clam, a marine bivalve mollusc in the family Glycymerididae, the bittersweet clams.

Synonyms

Arca insubrica Brocchi, 1814Arca nummaria Linnaeus, 1758Glycymeris insubrica Glycymeris violacescens Pectunculus cor Lamarck, 1805Pectunculus nudicardo Lamarck, 1819Pectunculus obliquatus Rayneval & Ponzi, 1854Pectunculus pilosellus Risso, 1826Pectunculus purpurascens M' Andrew, 1854Pectunculus reticulatus Risso, 1826Pectunculus transversus Lamarck, 1819Pectunculus zonalis Lamarck, 1819

Description

Glycymeris nummaria var. insubrica
Right and left valve of the same specimen:

The shell of an adult Glycymeris nummaria can be as large as. It is quite thick, almost circular in shape, with a sculpture of radiating striae and fine concentric lines. The surface is dull and may be dark or pale brown, but also whitish-yellowish. Inside of the shell is glossy, white or pale yellow, often with irregular brown markings.

Distribution and habitat

This species is widespread from Norway to the Mediterranean Sea. It lives in sandy-muddy gravels offshore to depths of about.