Cyclopecten Verrill, 1897

Dijkstra, Henk H. & Beu, Alan G., 2018, Living Scallops of Australia and Adjacent Waters (Mollusca: Bivalvia: Pectinoidea: Propeamussiidae, Cyclochlamydidae and Pectinidae), Records of the Australian Museum (Rec. Aust. Mus.) 70 (2), pp. 113-330 : 148

Cyclopecten Verrill, 1897

Cyclopecten Verrill, 1897: 70 . Type species (by subsequent designation, Sykes et al., 1898): Pecten pustulosus Verrill (1873: 14) ; Recent, near Georges Bank, off Newfoundland, Canada, 274 m.

Xenamussium Oyama, 1944: 244 (proposed as a subgenus of Propeamussium ). Type species (by original designation): Pecten hoskynsi Forbes (1844: 146, 192); Recent, “ Asia minor ” [= off Turkey].

Diagnosis. Shell equivalve, small, circular in most species, laterally compressed, prodissoconch smooth, weakly inflated; left valve of most species sculptured with radial and/or commarginal costellae or striae, right valve with commarginal lamellae; auricles unequal; byssal notch welldeveloped; without internal radial riblets.

Distribution. Paleocene?, Oligocene–Recent ( Waller, 2011). Cosmopolitan, subtidal to hadal (Hayami & Kase, 1993: 59). Most representative Cyclopecten species from the Indo-West Pacific region, however, live in deep water (Habe, 1977; Bernard, 1983; HHD, unpubl. data).

Discussion. Verrill (1897: 70) mentioned in his description “few pectinidial teeth [= ctenolium], byssus and byssal threads”, which are based on “ Cyclopecten ” circularis (G. B.