A new super narrow-ranged endemic Phoxinus minnow (Leuciscidae) from the Caucasus

By

Artaev, Oleg N.
Turbanov, Ilya S.
Bolotovskiy, Aleksey
Gandlin, Alexander
Levin, Boris Aleksandrovich

Type

Article

Date of Publication

2025-6-25

Original Publication

Zoosystematics and evolution

Volume

101

Series / Issue

Issue: 3

Pages

1137--1154

Subjects

Biodiversity , Conservation , Freshwater fishes , integrative taxonomy , karst springs , Kuban Basin , locally restricted species

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia Pensoft

Identifiers

DOI: https://doi.org/10.3897/zse.101.153548

 

Abstract

A new species, Phoxinus ayukensissp. nov., from the Kuban basin (Northwestern Caucasus) is described. This species has an extremely narrow range of approximately 5–7 km in a seasonally almost drying stream within the karstic region. The new species has a moderate genetic distance in cytochrome b mtDNA (p-distance = 0.026 ± 0.005) from geographically and genetically close species in the Kuban basin—P. adagumicus—and differs from all known Phoxinus species by a highly increased number of scales in the lateral series: 87–105 (mean 97.7), differs from other species from Eastern Europe and the Caucasus (P. adagumicus, P. chrysoprasius, P. colchicus, and P. isetensis) by an increased frequency of occurrence of seven rays in the pelvic fin (ca. 35%) and an increased number of scales between bases of dorsal and anal fins (32–41, mean 36.7). Morphologically, the new species is the most different from the other Caucasian species, but it is closer to the Northern minnow P. isetensis; that might be explained by phenotypic convergence caused by adaptation to cold waters. The range of the new species is limited by waterfalls in the upper reach of the Ayuk Stream, where subterranean water outlets probably contributed to its survival. The role of Pleistocene glaciations in shaping the modern distribution and environmental differences in evolutionary divergence of Caucasian Phoxinus is highlighted. Low genetic diversity coupled with extremely limited range within the seasonally half-drying stream suggests a high rank of protection for new species.