The ratio of the number of vertebrae in the trunk and in the caudal region of the vertebral column is investigated in 26 recent and 12 extinct species of cyprinids representing 20 genera of the subfamily Leuciscinae of the family Cyprinidae. In the space of the applied characters the species form, with few exceptions, two discrete, nonoverlapping statistical populations. The hiatus between them increases from oligovertebral species to multivertebral species. The absolute and relative elongation of the caudal region of the vertebral column is but weakly related to elongation of the anal fin within tribes and taxa of lower rank. This relationship manifests itself only when the tribes are compared. In the subfamily Leuciscinae, the production of forms was accompanied, as a rule, by positively correlated changes in the number of vertebrae in the considered regions. Possible causes of the observed discreteness and the significance of the discovered regularities for evolutionary systematics of the subfamily Leuciscinae are discussed.
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