A numerical taxonomic study of several Cobitis species (Pisces, Cobitidae) based on their cytogenetic features.

Some of the cytogenetical features (known also as chromosomal sets in karyotypes of polyploid forms) of Cobitis species in Poland and in other populations from Russia, the Czech Republic and England were compared using a numerical taxonomy method in order to reveal the relationships between them. The results obtained confirmed that in addition to C. taenia and C. elongatoides, C. tanaitica took part in the origin of polyploids from Poland. The numerical taxonomy method, revealing the relationships between the Cobitis fish species, provided evidence for assigning them into two groups: one containing C. taenia, C. tanaitica and C. melanoleuca with karyotypes dominated by uniarmed chromosomes and the second consisting of C. elongatoides and C. vardarensis with karyotypes dominated by biarmed chromosomes.