Craniological Features of the Italian Spined Loach Cobitis bilineata (Cobitidae)

The first craniological description of the Italian spined loach Cobitis bilineata, originally described as a variety of C. taenia, and a comparative analysis of its characteristics with previously studied Cobitis species are presented. In terms of the general structure of the skull, the number of bones and their shape, the Italian spined loach is closest to the previously described C. melanoleuca, the species turned out to be very phylogenetically distant. Thus, craniological features do not show correspondence with the genetic divergence and demonstrate significant stability within the genus Cobitis. Therefore, further molecular studies are of great importance to discover new cryptic species in these fish.