(Turton, 1822)

Description:
Shell is fragile, flat, equivalve with a smooth margin. Inequilateral, beaks just behind the midline, directed inwards. Outline of shell is broadly oval with the dorsal margins curved and ventral margin almost straight. Ligament is internal, below and behind the beaks. Sculpture of very fine concentric lines and a few microscopically small pits puncturing the shell surface about the umbones. Growth stages are clear. Each valve with a small central cardinal tooth. Right valve with two anterior and two posterior laterals; left valve with one anterior and one posterior lateral. Muscle scars are indistinct, adductors about equal. Pallial line is not indented by a sinus (H. nitidum-drawing).

Size:
Up to 3.2 mm in length.

Colour:
Dirty white, sometimes translucent. Periostracum light yellow. Interior of shell is white, sometimes translucent.

Animal:
The mantle which is fringed with long tentacles, protrudes nearly all round, and the foot can be flattened in such a manner that it resembles the foot of a snail and it is used in similar fashion. Foot is bluish, flecked with white; extends in front to form a siphon.

Habitat:
Gravelly and stony sand, offshore between 15-165 m.

Distribution:
All around the British Isles, the Norwegian Sea and Baltic south to the Iberian Peninsula, the Bay of Tangiers and into the Mediterranean (Distr. H. nitidum).

Kingdom Animalia
Phylum Mollusca
Class Bivalvia
Subclass Heterodonta
Order Veneroida
Family Leptonidae
Genus Hemilepton
Species Hemilepton nitidum

Status in World Register of Marine Species

Accepted name: Hemilepton nitidum (Turton, 1822)

Scientific synonyms and common names

Lepton nitidum Turton, 1822
Lepton nitidum var. laevis Jeffreys, 1864
Lepton nitidum var. lineolata Jeffreys, 1864
Lepton nitidum var. pisidialis Jeffreys, 1864
Erycina prismatica Cossmann & Peyrot, 1911
Semierycina nitida Turton, 1822
Erycina nitida

Aartsen, J.J. van, 1996. Galeommatacea and Cyamiacea: part II. La Conchiglia, 281.

Seaward, D.R., 1990. Distribution of the marine molluscs of north west Europe. Nature Conservancy Council.

Step, E., 1927. Shell life. 421 pp. Frederick Warne & Co., LTD, London.

Tebble, N., 1966. British Bivalve Seashells. 212 pp. Trustees of The British Museum (Natural history). London.

You can continue searching for Hemilepton nitidum on one of these Web sites:

Fauna Europaea (animals) | IOPI (plants) | NCBI (genetic)

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