Circumarctic to Primorsky Krai and northern Japan, to British Columbia, to northern Brasil and into Mediterranean. This is usually a deep water species, found from continental shelf and slope down to abyssal depths; also encountered in the infralittoral of scottish marine lochs (MBSBI); range 25-2740m.

« Posterior folds obsolete. Posterior dorsal margin long and sloping to meet ventral margin at a narrow but rounded angle. Ventral and anterior margins form a broadly roundded curve dipping into sunken anterior dorsal margin. Lunule small, excavated but visible mostly from internal view or in decorticated shells. Umbo prominent, projecting anteriorly. Hinge weak, cardinal tubercle in LV, RV with marginal flange below beak. Ligament mostly internal on a sunken resilifer and one half the length of the dorsal margin. » – Graham Oliver, Killeen & Ockelmann: “The Thyasiridae (Mollusca: Bivalvia) of the British Continental Shelf and North Sea oil fields: an identification manual”, Studies in Marine Biodiversity and Systematics from the National Museum of Wales. BIOMÔR Reports, 3, Cardiff 2002 p.54.