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Issue: Vol. 5821 No. 1: 28 May 2026
Type: Article
Published: 2026-05-28
DOI: 10.11646/zootaxa.5821.1.1
Page range: 1-22
Abstract views: 19
PDF downloaded: 0

Integrative description of Testechiniscus impenetrabilis sp. nov. (Heterotardigrada: Echiniscoidea) from Novaya Zemlya (Russia), with a discussion on the genus diagnosis and distribution

Department of Invertebrate Zoology; Faculty of Biology; St. Petersburg State University; 7/9 Universitetskaya Emb.; St. Petersburg 199034; Russia; Marine Research Laboratory; Zoological institute of Russian Academy of Sciences; Universitetskaya Emb.; St. Petersburg 199034; Russia
Department of Invertebrate Zoology; Faculty of Biology; St. Petersburg State University; 7/9 Universitetskaya Emb.; St. Petersburg 199034; Russia; Marine Research Laboratory; Zoological institute of Russian Academy of Sciences; Universitetskaya Emb.; St. Petersburg 199034; Russia
Tardigrada Echiniscidae morphology new record taxonomy zoogeography

Abstract

In this paper we describe Testechiniscus impenetrabilis sp. nov., a new tardigrade species from Novaya Zemlya, Russia, using morphological and morphometric analyses conducted with the use of light and scanning electron microscopy, as well as genetic analysis based on four molecular markers (three nuclear: 18S rRNA, 28S rRNA, ITS-1, and a mitochondrial: COI). Upon examination of both type species T. spitsbergensis and T. impenetrabilis sp. nov., we describe internal leg plates as a new character for the genus Testechiniscus, thereby amending the genus diagnosis. This study also presents new data on the geographic distribution of Testechiniscus.

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How to Cite

Tsvetkova, A.Y. & Tumanov, D.V. (2026) Integrative description of Testechiniscus impenetrabilis sp. nov. (Heterotardigrada: Echiniscoidea) from Novaya Zemlya (Russia), with a discussion on the genus diagnosis and distribution. Zootaxa, 5821 (1), 1–22. https://doi.org/10.11646/zootaxa.5821.1.1