Morphometric variation of hybridizing species and gynogenetic biotypes of spined loaches (Cobitidae: Cobitis) in river systems of Ukraine

S. V.  Mezhzherin; L. I.  Pavlenko; A. O.  Tsyba; T. V.  Saliy; M. A.  Ghazali

doi:10.15407/zoo2020.04.285

S. V. Mezhzherin I.I. Schmalhausen Institute of Zoology NAS of Ukraine, vul. B. Khmelnytskogo, 15, Kyiv, 01030 Ukraine http://orcid.org/0000-0003-2905-5235
L. I. Pavlenko I.I. Schmalhausen Institute of Zoology NAS of Ukraine, vul. B. Khmelnytskogo, 15, Kyiv, 01030 Ukraine http://orcid.org/0000-0002-5295-4258
A. O. Tsyba I.I. Schmalhausen Institute of Zoology NAS of Ukraine, vul. B. Khmelnytskogo, 15, Kyiv, 01030 Ukraine https://orcid.org/0000-0001-5838-0948
T. V. Saliy I.I. Schmalhausen Institute of Zoology NAS of Ukraine, vul. B. Khmelnytskogo, 15, Kyiv, 01030 Ukraine https://orcid.org/0000-0003-2961-1326
M. A. Ghazali I.I. Schmalhausen Institute of Zoology NAS of Ukraine, vul. B. Khmelnytskogo, 15, Kyiv, 01030 Ukraine http://orcid.org/0000-0001-9195-0914

DOI: https://doi.org/10.15407/zoo2020.04.285

Keywords: Morphometry, Diagnostics, diploid-polyploilex, spined loaches, Cobitis

Abstract

To test the possibility of identifying the species and biotypes of spined loaches of the complex Cobitis elongatoides – taenia – tanaitica using body morphometric characteristics, we considered a pool of specimens from different river systems of Ukraine. The sample included three parental species and seven hybrid biotypes with various genome combinations, and the morphometry was based on 23 body parameters and 26 derivative indices. The variability was analyzed by standard and multivariate statistics. Neither any one measurement, nor their combination allowed identifying the specimens with 95-100% probability. Pooled, samples had no internal logic of morphological remoteness of hybrid biotypes and parental species in regards to their genetic similarity. Morphometry’s low resolution in case of pooled samples is linked to the specifics of body shape and significant geographic variability which partially evens out the between-group differences, while within samples the resolution was higher without reaching even 95% diagnostical certainty. All in all, the resolutions obtained for morphometric parameters are within results obtained in similar studies for other hybrid fishes.