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

Key to species of Cyclopecten from Australia

1 Shell c. 3 mm high, circular, opaque, whitish or creamy, lv with coarse reticulate sculpture with scaly intersections, rv with closely spaced commarginal lamellae, with rudimentary internal riblets in some specimens ........................................................................... C. cancellus

—— Shell small, circular, lv commarginally scultured with erect hollow spines, internal riblets lacking ....................................................................................... 2

2 Shell c. 6 mm high, opaque, whitish, lv with commarginal lamellae and erect hollow spines on lamellae, and with intercalated antimarginal microscupture on late growth stage, rv similar but with weaker sculpture ......................................................................... C. horridus

—— Shell small, subcircular, lv with weak reticulate sculpture in early stage .................................................................................................................................. 3

3 Shell c. 7.5 mm high, translucnt white, lv with weak reticulate sculpture in early ontogeny, other parts of disc smooth, rv with commarginal lamellae transformed into rounded lirae, no internal riblets .................................................................................. C. powelli

—— Shell small, circular, lv with delicate reticulate sculpture, no internal riblets ............................................................................................................................ 4

4 Shell c. 6 mm high, opaque, whitish, lv with delicate, closely spaced radial and commarginal sculpture, rv with commarginal lamellae ................................................................................................ C. kapalae

—— Shell small, circular, lv with radial and commarginal sculpture, in central part reticulate, no internal riblets .............................................................. 5

5 Shell c. 10 mm high, semi-translucent, whitish, lv with prominent commarginal lamellae and weaker radial riblets, rv with delicate commarginal lirae ........................................................................ C. reticulatus Sowerby I, 1835) [= Lissochlamys exotica (Dillwyn, 1817) , a pectinid species mistakenly included by Verrill].A ctenolium and byssus are not present in Cyclopecten . Many Cyclopecten species have been described and placed in different genera, for example Delectopecten (a pectinid genus) (Hertlein, 1969; Knudsen, 1970; Habe, 1977; Bernard, 1978; Rombouts, 1991) or Palliolum (a pectinid genus) (Abbott, 1974, in part). Several described “ Cyclopecten ” species from the subantarctic region belong in Cyclochlamys (see below) (Dijkstra, unpubl. data).