The diversity of the Baikal lineage of Hydra oligactis Pallas, 1766: molecular and morphological evidence

Tatiana E Peretolchina; Igor V Khanaev; Ilya V Enushchenko; Dmitry Y Sherbakov; Lyubov S Kravtsova

doi:10.3897/zookeys.912.46898

The diversity of the Baikal lineage of Hydra oligactis Pallas, 1766: molecular and morphological evidence

Zookeys. 2020 Feb 17:912:1-12. doi: 10.3897/zookeys.912.46898. eCollection 2020.

Authors

Tatiana E Peretolchina¹, Igor V Khanaev¹, Ilya V Enushchenko¹, Dmitry Y Sherbakov¹, Lyubov S Kravtsova¹

Affiliation

¹ Limnological Institute SB RAS, Ulan-Batorskaya Str., 3, 664033, Irkutsk, Russia Limnological Institute SB RAS Irkutsk Russia.

Abstract

In this paper, molecular analyses of Baikal hydras from the 'oligactis group', based on COI and ITS1-5.8S-ITS2, and morphological analysis of their holotrichous isorhizas, were performed. Low genetic diversity and shared haplotypes were found between Hydra oligactis Pallas, 1766 and Hydra baikalensis Swarczewsky, 1923 specimens, which is evidence of the mixing of these lineages. Genetic distances among all Baikal hydras (0.006) were less than the interspecific distances of other hydras. The size of hydras and proportions of their holotrichous isorhizas varied depending on microhabitat and environmental conditions. Our combined molecular and morphological approach proves that H. baikalensis is synonymous with H. oligactis.

Keywords: Baikal hydras; holotrichous isorhizas; phylogeny; taxonomy.

Tatiana E. Peretolchina, Igor V. Khanaev, Ilya V. Enushchenko, Dmitry Y. Sherbakov, Lyubov S. Kravtsova.