Ciclopecten fluctuatus (Bavay, 1905)

Dijkstra, Henk H. & Maestrati, Philippe, 2008, New species and new records of deep-water Pectinoidea (Bivalvia: Propeamussiidae, Entoliidae and Pectinidae) from the South Pacific, Mémoires du Muséum national d'Histoire naturelle 196, pp. 77-114 : 102-103

Ciclopecten fluctuatus (Bavay, 1905)

Pecten (Chlamys) fluctuatus Bavay, 1905: 188 , pl. 17, figs 3a-b.

Other reference:

Ciclopecten fluctuatus - Dijkstra & Marshall 2008: 48 , figs 35, 40c, 40g.

MATERIAL EXAMINED.— The type material (see Dijkstra 1995: 51). Marquesas. MUSORSTOM 9: stn CP 1272, 7˚55’S, 140˚44’W, 660-680 m, 1 spm .

DISTRIBUTION. — Andaman Sea , Indonesia, New Caledonia and Vanuatu; live in 225-566 m ( Dijkstra 2001: 91). New record for the Marquesas Islands. Present specimen live in 660-680 m.

REMARKS. — This species was formerly placed in Delectopecten (see Dijkstra 2001). However, examination of Pliocene material of C. peloritanus , the type species of Ciclopecten , from Italy, indicates that the present species is morphologically closer to Ciclopecten than to Delectopecten . It has similar commarginal undulations and antimarginal microsculpture. For a description of C. fluctuatus see Dijkstra (1995: 51).

The present specimen from the Marquesas is similar to the holotype from the Andaman Sea, but differs slightly in size (15 mm in height, holotype 10 mm), sculpture of the left valve (fine radial sculpture, holotype somewhat coarser) and the presence of delicate commarginal sculpture (nearly lacking in holotype). However, intermediate variants are also known (MNHN). Other characters are identical.