Species Account

Katadesmia cuneata (Jeffreys, 1876)

Nuculanoidea : Malletiidae

Tebble name: n/a
Smith & Heppell name: Malletia cuneata Jeffreys, 1876

To size: To 10mm. Shell Structure: Thin, fragile. Equivalve: Equivalve. Equilateral: Inequilateral, beaks situated to the anterior of midline, approximately 35-40% of total length from anterior end. Tumidity: Slightly inflated. Outline: Elongate-oval: antero-dorsal margin short, gently sloping; anterior end well rounded; postero-dorsal margin long, straight and slightly sloping, with a dorsal margin - posterior margin junction; posterior end slightly pointed weakly rostrate especially in larger specimens. Ventral margin long, shallowly rounded, usually with a straight section in the centre. Umbo broad, moderately prominent, and slightly pointed.

Sculpture: Virtually smooth, with only very faint, closely spaced concentric lines. Margin: Smooth. Ligament: External, opisthodetic, well-developed, very short with the posterior part 3-4 times the length of the anterior part. Hinge: Taxodont: Hinge plate broadens away from the umbos, sloping slightly to the anterior and posterior. Fat, chevron-shaped teeth up to 18 in posterior and 12 in anterior. Periostracum: Glossy, greyish. Colour: Translucent white. Additional Characters: The hind-gut forms a simple, rounded loop on the right side of the body.

Distribution & Ecology

Rockall Trough in depths >2000m. Widespread in the North and South Atlantic deep-sea basins, also known from the Indian, Pacific, Arctic and Antarctic Oceans. In depths ranging from 1780 to >4700m.

Depth Range
Abyssal Rise (2000 - 4000m)
Abyssal Plain (4000m +)

Additional Information & Related Species

Related Species

Nuculanoidea : Malletiidae


Listed are literature citing Katadesmia cuneata (Jeffreys, 1876). Reference containing the species Type Description is highlighted.

Jeffreys J G 1876. New and peculiar Mollusca of the Pecten, Mytilus and Arca families, procured in the Valorous expedition. Annals and magazine of natural History. (4)18: 424-436.
Olabarria C. 2005. Patterns of bathymetric zonation of bivalves in the Porcupine Sea Bight and adjacent abyssal plain, NE Atlantic. Deep-Sea Research I. 52: 15-31.
Sanders H.L. & Allen J.A. 1985. Studies on deep sea Protobranchia (Bivalvia): the family Malletiidae. Bulletin of the Natural History Museum, London (Zoology). 49: 195-238.


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Record last modified: 22/03/2016