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Issue: Vol. 5792 No. 1: 10 Apr. 2026
Type: Article
Published: 2026-04-10
DOI: 10.11646/zootaxa.5792.1.6
Page range: 116-136
Abstract views: 63
PDF downloaded: 3

Description of two new Nematoda species: Calyptronema pumila sp. nov. (Enoplida: Enchelidiidae) and Thalassomonhystera sinica sp. nov. (Monhysterida: Monhysteridae) from the Yellow Sea

College of Agriculture and Biology; Liaocheng University; Liaocheng 252059; P. R. China
College of Agriculture and Biology; Liaocheng University; Liaocheng 252059; P. R. China
Nematoda biodiversity China free-living marine nematodes species list subtidal zone

Abstract

Two new species of free-living marine nematodes found in the Yellow Sea are described and illustrated. Calyptronema pumila sp. nov. is characterized by comparatively smaller body size with conico-cylindrical tail; rounded males cephalic region set off by a transverse ring; amphideal fovea irregularly oblong; slender spicules 2.3 cloacal body diameter long; thin gubernaculum 24 µm long; precloacal supplements consisting of a ventral setigerous papilla and five paired subventral setigerous papillae; outer labial setae and cephalic setae in females relatively short and tail relatively long. The presence of a ventral papilliform and five paired subventral papilliform precloacal supplements can separate the new species from all other known species of the genus. Thalassomonhystera sinica sp. nov. is characterized by slender and fusiform body; finely striated cuticle; outer labial and cephalic setae 2–2.5 μm long; circular amphideal fovea located far posterior from the anterior end; spicules cuticularized, slightly S-shaped with a twisted appearance; gubernaculum absent; tail conico-cylindrical without terminal setae. The new species differs from other known species of the genus in having strongly cuticularized, spicules slightly S-shaped with a twisted appearance, and lacks gubernaculum. Updated keys for identification of valid species of both Calyptronema and Thalassomonhystera are provided.

 

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How to Cite

Zhai, H. & Li, X. (2026) Description of two new Nematoda species: Calyptronema pumila sp. nov. (Enoplida: Enchelidiidae) and Thalassomonhystera sinica sp. nov. (Monhysterida: Monhysteridae) from the Yellow Sea. Zootaxa, 5792 (1), 116–136. https://doi.org/10.11646/zootaxa.5792.1.6