Tu, N. D.; Smol, N.; Vanreusel, A.; Thanh Nguyen Vu. (2011). Six new species of the genus Onyx Cobb, 1891 (Nematoda: Desmodoridae) from coastal areas in Vietnam. Russian Journal of Nematology. 19(1): 1-20.
Tu, N. D.; Smol, N.; Vanreusel, A.; Thanh Nguyen Vu
Six new species of the genus Onyx Cobb, 1891 (Nematoda: Desmodoridae) from coastal areas in Vietnam
Six new species of the genus Onyx are described from different coastal zones in Vietnam based on samples collected between 2004 abd 2010. Onyx callgiallellsis sp. n. is characterised by the fact that males have 14-16 equal-sized nod equal-distantly arranged sigmoidal precloacal tubular shaped supplements. Onyx blamei sp. n. is characterised by sexual dimorphism in the shape of the amphidial fovea. The male has an atypical arnphid with posterior part spiral shaped with 2.5 turns and anterior part hook shaped, whereas the amphidial fovea in the female is simply multispiral with 2.25 turns. Onyx arielltalis sp. n. is characterised by its very long cephalic setae nod the presence of 18 light-refractive, slightly S-shaped, precloacal tubular supplements in the males. Onyx cobbi sp. n. is also characterised by its sexual dimorphism in the shape of the arnphidial fovea: an elongated loop in the male nod a multispiral in the female. There are 15 slightly S-shaped, precloacal supplements. The noterior supplement is half the size of the others. Onyx paradimorphlls sp. n. is characterised by a multispiral amphidial fovea, spicules regularly bent, strongly cuticularised, 15 S-shaped supplements nod 5 papillae with setae within tbe spicules region. Onyx mallgrovi sp. n. is characterised by 17-23 supplements with a complex structure: anterior part is sigmoidal-shaped, posterior part is hook-shaped and by its very short tail with dorsally curved tip.