Tatyana V. Naumova, PhD, Senior Researcher of the Limnological Institute, Siberian Branch of the RAS (664033, Russia, Ulan-Batorskaya, 3, P.O. box 278); ); iD ORCID:; e-mail:
Vladimir G. Gagarin, Dr. Sc., Chief Researcher of the Papanin Institute for Biology of Inland Waters RAS (152742, Russia, Yaroslavl Region, Nekouzskiy district, Borok town, 109); iD ORCID:; e-mail:

Reference to article

Naumova T.V., Gagarin V.G. 2023. Two new nematode species of the genus Eutobrilus (Nematoda, Triplonchida) from Lake Baikal (Russia). Nature Conservation Research 8(2): 106–112.

Section Short Communications

This paper describes and illustrates two new nematode species of the genus Eutobrilus found in Lake Baikal. Eutobrilus tsalolikhini sp. nov. is most similar to E. mirandus and E. obesus in body size and spicules length. It differs from E. mirandus in its thicker body, longer outer labial setae, larger stoma, and more supplements. It differs from E. obesus in a shorter tail, farther location of vulva from the anterior body end, longer outer labial setae, and more supplements. Eutobrilus olkhonensis sp. nov. is most similar to E. fortis and E. godlewskii in body size and supplements location but differs from both species in a thicker body, longer tail in males, shorter spicules, and fewer supplements.


diversity, free-living nematodes, morphology, taxonomy, Tobrilidae

Artice information

Received: 04.10.2022. Revised: 22.12.2022. Accepted: 27.01.2023.

The full text of the article

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