Species Account

Arca imbricata Bruguière, 1789

Arcoidea : Arcidae

Tebble name:
Smith & Heppell name:

To size: To 65 mm. Shell Structure: Thin, robust. Equivalve: Equivalve. Equilateral: Inequilateral, beaks to anterior. Tumidity: Tumid. Outline: Elongated boat-shaped. Ridge/keel running fromumbo to ventral posterior point. Can appear slightly twisted. Byssal gape is fairly wide. Clear from one valve as the ventral margin is indented.

Sculpture: Radial ribs and concentric ridges, giving a radial beadlet sculpture. Margin: Slightly crenulated margin – an extension of the sculpture. Ligament: Duplivincular, diamond shaped as viewed from above. In large specimens it becomes very elongated but does not run the entire length of the dentition. Hinge: Taxodont. Numerous identical tiny teeth set on a thin hinge plate. Pallial Musculature: Anterior adductor round, slightly smaller than posterior, which is oval. Periostracum: Brown, thick, sometimes covers the shell (giving its common name of Mossy Ark). Colour: Dirty white internally. External dirty white to brown. Sometimes brown covers posterior half of shell.

Distribution & Ecology

Native range from North Carolina through the Caribbean to Brazil attached to rocks in shallow waters.

In Britain and Ireland it has been found in Sennen, Cornwall.

Depth Range

Additional Information & Related Species


Listed are literature citing Arca imbricata Bruguière, 1789. Reference containing the species Type Description is highlighted.

Bruguière, J.G. 1789-1792. Encylopédie méthodique ou par ordre de matières. Histoire naturelle des vers volume 1. Paris: Pancoucke. i-xviii, 1-344.


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Record last modified: 03/03/2022