Channichthys mithridatis, a new species of icefishes (Perciformes: Notothenioidei: Channichthyidae) from the Kerguelen Islands (East Antarctica), with comments on the taxonomic status of Channichthys normani

Abstract

The sub-Antarctic genus Channichthys, endemic for the area of the Kerguelen-Heard Plateau of the Southern Ocean, includes 7 nominal species of unicorn icefishes: C. rhinoceratus Richardson, 1844, C. rugosus Regan, 1913, C. velifer Meissner, 1974, C. panticapaei Shandikov, 1995, C. irinae Shandikov, 1995, C. bospori Shandikov, 1995 and C. aelitae Shandikov, 1995. The last four were described on the basis of materials collected by the 1990 research expedition (the 23rd cruise of R/V Professor Mesyatsev) of YugNIRO to the Kerguelen Islands area. The lately described C. normani Balushkin, 1996 is considered to be a junior synonym of C. panticapaei. In the present paper a new, the eighth species of genus Channichthys is described – C. mithridatis sp. n. – green icefish (on the basis of 29 specimens), collected in the same (R/V Professor Mesyatsev) cruise. The new species is closely related to C. irinae, but in the most differs from it by the uniserial gill-rakers, frequency distribution and greater number of spines in first dorsal fin, relatively smaller eye, large mouth and by traits of biology – C. mithridatis is piscivorous, while C. irinae is a typical zooplankton consumer.