Species Account

Isognomon radiatus (Anton, 1838)

Pterioidea : Isognomonidae

Tebble name:
Smith & Heppell name:

To size: To 82 mm. Shell Structure: Thin, fragile shell. Equivalve: Equivalve. Equilateral: Inequilateral, beaks to the anterior. Tumidity: Flattened. Outline: Irregular, elongated oval.

Sculpture: Smooth but with flaky periostracum. Margin: Smooth. Ligament: Divided into rectangular brown squares, number of which depends on size/age. Hinge: Edentulous. Pallial Musculature: Monomyarian, large posterior adductor muscle is elongated oval. Colour: Nacreous internally, no clear demarcation of end, fades to shell colour. External is tan to brown with pale purple-white radial rays.

Distribution & Ecology

In native range Florida to Bermuda, Barbados and throughout Caribbean south to Brazil in shallows attached to rocks.

In Britain and Ireland it has been found in Cornwall attached to a piece of car running board, plastic pails and a plastic drum.

Depth Range

Additional Information & Related Species

Related Species

Pterioidea : Isognomonidae


Listed are literature citing Isognomon radiatus (Anton, 1838). Reference containing the species Type Description is highlighted.

Anton, H.E. 1838. Verzeichniss des Conchylien xvi + 110pp..


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Record last modified: 03/03/2022