Taxonomic studies of the Antarctic icefish genus Cryodraco Dollo, 1900 (Notothenioidei: Channichthyidae)

Based on a meristic and morphometric study of 101 specimens, we recognise
2 valid species in the Antarctic channichthyid genus Cryodraco: Cryodraco
antarcticus Dollo, 1900 and C. atkinsoni Regan, 1914. Although the species
overlap in most meristic and morphometric characters, we have
distinguished
several reliable characters for diagnosis and identification.
Multidimensional scaling, a nonparametric multivariate technique, clearly
separates the two species on the basis of pelvic fin length, head length,
number of second dorsal fin rays and origin of the lower lateral line
relative to the anal fin rays. We provide a revised identification key to
the species of Cryodraco. From a zoogeographical point of view, C.
antarcticus has a circum-Antarctic distribution whereas C. atkinsoni is
largely confined to the East Antarctic Zoogeographic Province.