New genus Asymmelaimus gen. n., sp n. and new marine nematode species of the subfamily Dorylaimopsinae de Coninck, 1965 (Comesomatidae Filipjev, 1918) from Halong Bay, Vietnam

Abstract

One new genus and one new species are described from Halong Bay, Vietnam: Asymmelaimus vietnamicus gen. n., sp. n. and Dorylaimopsis halongensis sp. n. Asymmelaimus vietnamicus gen. n., sp. n. is characterized by an asymmetrical head with the anterior part of the buccal cavity leaning to the dorsal side and a narrow posterior part with weakly cuticularized walls and one dorsal and two ventrosublateral small teeth situated at the base of the anterior part, and a cuticular ornamentation consisting of one or two longitudinal rows of dots. Dorylaimopsis halongensis sp. it. is characterized by the head set off from the body by constriction, massive spicules with a 'velum' and a long tail (11.3 to 13.6 anal body diameters)