Cyclaspis longicaudata SARS 1865

CYCLASPIS LONGICAUDATA SARS, 1865

Material examined: New Caledonia, BIOCAL, stn CP57, 23°43.26′S, 166°58.06′E, 1490–1620 m, 1.ix.1985, 1 preadult female, 1 juvenile, 1 manca (MNHN-Cu1086); stn DS59, 23°56.21′S, 166°41.10′E, 2650 m, 2.ix.1985, 1 preadult male, 1 preadult female, 1 juvenile (MNHN-Cu1087).

Diagnosis: Carapace globose and smooth without ridges or tubercles; pseudorostral lobes meeting just in front of the eyelobe. Uropods as long as pleonite 6, peduncle half length than unarmed rami.

Remarks: Specimens agree with the description of Cyclaspis longicaudata Sars, 1865 a previously known from the North Atlantic, the Mediterranean and the south-west Atlantic. Comparison of the present material with specimens from the Bay of Biscay (north-eastern Atlantic) and eastern Mediterranean reveals no significant differences between them.

Day (1978) assigned the material collected off the South African coast between 460 and 1300 m depth to Cyclaspis spectabilis Zimmer, 1908. However, no specimen has the transverse suture across the carapace, diagnostic in C. spectabilis and neither has the plumose setae on the inner margin of the uropod exopod. Without these features, the South African material is closely related to C. longicaudata but Day (1978) pointed out the greater length of the uropod peduncle as a main difference. However, in her description she mentioned that pleonite 6 is ‘more than twice length of peduncle of uropods’ and ‘rami subequal in length, about twice length of peduncle’. Both statements allow this material to be included within the range of variation of C. longicaudata (Fig. 13).

Cyclaspis longicaudata may have a wider distribution than the south-eastern Atlantic, the Indian Ocean and the west Pacific or, conversely, comprises a group of sibling species that only a molecular analysis will be able to separate.