Species Account

Diplodonta rotundata (Montagu, 1803)

Ungulinoidea : Ungulinidae

Tebble name: Diplodonta rotundata (Montagu)
Smith & Heppell name: Diplodonta rotundata (Montagu, 1803)

To size: To 25mm. Shell Structure: Thin, solid. Equivalve: Equivalve. Equilateral: Inequilateral, beaks to anterior. Tumidity: Moderately tumid. Outline: Subcircular, posterior dorsal margin short, almost straight to a broadly rounded posterior margin. Anterior and posterior dorsal margins roughly equal in length, narrowly rounded anterior margin, broadly rounded posterior margin, medially rounded ventral margin.

Sculpture: Concentric lines. Growth stages clear. Margin: Smooth. Ligament: More than half the length of posterior dorsal margin and yellowy-brown. On a nymphal plate. Hinge: Two cardinals in each valve, LV anterior and RV posterior bifid. No laterals. Pallial Musculature: No pallial sinus. Pallial line continuous. Adductors equal in size. Periostracum: Thin, creamy-yellow. Colour: White.

Distribution & Ecology

A shallow burrower into muddy sand at sublittoral and shallow shelf depths. Recent records are from the south and western sectors with older records from the Irish Sea and southwest of Scotland.

Depth Range
Continental Shelf (to 200m)

Additional Information & Related Species

Related Species

Ungulinoidea : Ungulinidae


Listed are literature citing Diplodonta rotundata (Montagu, 1803). Reference containing the species Type Description is highlighted.

Montagu G 1803. Testacea Britannica, or natural history of British shells, marine, land and the fresh-water, including the most minute: systematically arranged and embellished with figures Romsey, London. 606pp, 16pls.
Van Aartsen JJ 2000. European marine mollusca: Notes on less well-known species. XVI. Diplodonta eddystonia (Marshall, 1895), with notes on the European Diplodonta species. La Conchiglia. 297: 46-51.


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Record last modified: 17/05/2016