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Issue: Vol. 5757 No. 4: 9 Feb. 2026
Type: Article
Published: 2026-02-09
DOI: 10.11646/zootaxa.5757.4.2
Page range: 324-338
Abstract views: 17
PDF downloaded: 0

Three new species of Xyalidae (Nematoda: Monhysterida) from Argentinean coast

Laboratorio de Meiofauna Marina (LAMEIMA). Instituto de Diversidad y Evolución Austral; (IDEAus-CONICET). Bvard. Brown 2915; Puerto Madryn; Chubut; Argentina.
Laboratorio de Meiofauna Marina (LAMEIMA). Instituto de Diversidad y Evolución Austral; (IDEAus-CONICET). Bvard. Brown 2915; Puerto Madryn; Chubut; Argentina.
Nematoda Rhynchonema Prorhynchonema systematics free-living marine nematodes South America Argentina

Abstract

Three new species of free-living marine nematodes belonging to the family Xyalidae are described from the Argentinean coast: Rhynchonema paraseparatum sp. nov., Rhynchonema bicuspidatum sp. nov., and Prorhynchonema uncinoa sp. nov. Rhynchonema paraseparatum sp. nov. is characterized by an annulated cuticle without projections, L-shaped spicules, and a gubernaculum with dorsal projections. Rhynchonema bicuspidatum sp. nov. has an annulated cuticle with anterior and posterior projections, a uniquely shaped gubernaculum with two distal tips, and longitudinal bands along the mid-body. Prorhynchonema uncinoa sp. nov. is characterized by a gubernaculum with hook-like distal structures and amphids located well posterior to the buccal cavity. These findings expand the taxonomic knowledge and geographic distribution of Xyalidae in the Southern Hemisphere.

 

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How to Cite

Russo, V.L. & Pastor, C.T. (2026) Three new species of Xyalidae (Nematoda: Monhysterida) from Argentinean coast. Zootaxa, 5757 (4), 324–338. https://doi.org/10.11646/zootaxa.5757.4.2