Calanus sinicus Brodsky and C. jashmovi, nom. nov. (Copepoda : Calanoida) of the north-western Pacific Ocean: a comparison, with notes on the integumental pore pattern in Calanus s. str.

Abstract

Morphological features, records of distribution and seasonal occurrence of the calanoid copepods Calanus sinicus Brodsky, 1965, and C. orientalis Jashnov, 1975, are compared. Differences between the specimens corroborate the validity of both species. Synonymies are presented. Calanus syunpuensis Kurasige, 1931, cannot be assigned with certainty to either species as senior synonym; it is proposed that this name be treated as a nomen dubium. The preoccupied name C. orientalis Jashnov is replaced with the new name Calanus jashnovi.

The patterns formed by integumental organs, i.e. pores of integumental glands and sensilla, are compared between females of C. sinicus and C. orientalis and, further, between most species of Calanus s. str. These patterns support the division of the genus into the four groups established previously on the basis of other morphological characters. Within the pacificus group, C. sinicus and C. orientalis are set apart from the rest of the species by distinct common features of the urosomal pattern, but certain specific features separate the two species.