Species Account

Adontorhina similis Barry & McCormack 2007

Thyasiroidea : Thyasiridae

Tebble name: n/a
Smith & Heppell name: Thyasira pygmaea (Verrill & Bush, 1898)

To size: To 2.0mm. Shell Structure: Shell fragile, translucent. Equivalve: Equivalve. Equilateral: Slightly inequilateral, beaks just behind the midline. Tumidity: Inflated. Outline: Subovate, expanded anteriorly, distinctly longer than high; anterior dorsal margin initially horizontal then angled to short often truncated outer anterior dorsal margin; anterior broadly rounded; ventral margin long, gently curved; posterior subacute; posterior dorsal margin straight or slightly angled. Contour: Umbo prominent; Lunule area small, flattened; submarginal sulcus shallow, weakly defined, auricle very low.

Sculpture: Of weak concentric lines and growth stops. Margin: Inner margin smooth. Ligament: On a sunken resilifer extending to about half the length of the posterior dorsal margin. Hinge: Weak, a minute cardinal protuberance in RV and corresponding depression in LV; Margin under lunule thickened and minutely denticulate, denticulations also along posterior dorsal margin. Pallial Musculature: Muscle scars obscure. Periostracum: Thin, obsolete. Colour: Shell white, often with some rust-coloured deposits on posterior and anterior dorsal areas. Additional Characters: 1 demibranch.

Distribution & Ecology

Known with certainty from the shelf of central and north North Sea in depths from 85-160m. Also from Scottish sea lochs in depths as shallow as 25m. Also from the Porcupine Bank.
Suspension feeder/ partially chemotrophic. Dufour, 2005 found no symbionts but Ockelmann in Oliver & Killeen, 2002 describes the feeding mode that indicates the sulphur mining habit typical of chemosymbiotic species.

Depth Range
Continental Shelf (to 200m)

Additional Information & Related Species


Listed are literature citing Adontorhina similis Barry & McCormack 2007. Reference containing the species Type Description is highlighted.

Barry P J & McCormack G P 2007. Two new species of Adontorhina Berry, 1947 (Bivalvia: Thyasiridae) from the Porcupine Bank, off the west coast of Ireland. Zootaxa. 1526: 37-49.
Oliver P G & Killeen I J 2002. The Thyasiridae (Mollusca: bivalvia) of the British continental shelf and North Sea Oilfields. Studies in Marine Biodiversity and Systematics from the National Museum of Wales. BIOMOR Reports. 3: 1-73.


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Record last modified: 15/01/2014