The subfamily Myoxocephalinae of cottid fishes (Cottidae): Genetic divergence and phylogenetic relationships.

A comprehensive study based on molecular marker and karyotype analyses has provided evidence for the monophyly of the subfamily Myoxocephalinae, which includes the genera Myoxocephalus, Megalocottus, Microcottus, Porocottus, Enophrys and Argyrocottus. In addition, the karyotype of the threadfoot sculpin Argyrocottus zanderi Herzenstein 1892 has been studied for the first time. Marker traits of karyotypes identified 13 species among six cottid genera. As the molecular genetic results confirmed, the subfamily is divided into two groups corresponding to Enophrys and Myoxocephalus. The molecular genetic data did not support the formation of tribes within the subfamily Myoxocephalinae, as proposed earlier based on morphological characters. Moreover, the genera Trichocottus and Taurocottus should be excluded from the Myoxocephalinae. The evolutionary transformations of karyotypes in cottid fish tended towards a reduction in the number of chromosomes and chromosome arms.