Two new and two known species of the genus Eudorylaimus Andrássy, 1959 (Nematoda, Dorylaimoidea, Qudsianematidae) from Northeast China

Zookeys. 2025 May 9:1238:41-74. doi: 10.3897/zookeys.1238.138550. eCollection 2025.

Abstract

Two new and two known species of the genus Eudorylaimus belonging to the family Qudsianematidae are described and illustrated from Northeast China. Eudorylaimusblisterocaudatus sp. nov. is characterized by its 1.0-1.3 mm long body, lip region offset by constriction and 15-17 µm wide; odontostyle 1.0-1.2 times the lip region diameter long, odontophore 1.3-1.5 times the odontostyle length, pharyngeal expansion occupying ~ 41-47% of total neck length; V = 59-63%, uterus tripartite 1.3-3.8 times the corresponding body diameter, vulva post-equatorial, spicules 39-45 µm long, 6-8 irregularly spaced ventromedian supplements, tail conoid, sub-digitate with rounded terminus in both the sexes. Eudorylaimussaccatus sp. nov. is characterized by its 1.1-1.4 mm long body, lip region offset by constriction and 15.0-17.5 µm wide; odontostyle 1.0-1.2 times the lip region diameter long, odontophore 1.3-1.5 times the odontostyle length, pharyngeal expansion occupying ~ 44-48% of total neck length; uterus tripartite, 1.3-2.1 times the corresponding body diameter, V = 62-63.3%; tail conoid, dorsally convex, with sub-digitate terminus in both the sexes and males with 44-48 µm long spicules and 9-11 irregularly spaced ventromedian supplements. Two known species E.meridionalis and E.caudatus are reported for the first time from China and one male specimen of E.caudatus is recorded here for the first time.

Keywords: China; Qudsianematidae; nematode biodiversity; new species.