Two new free-living marine nematode species of the genus Pseudosteineria (Monohysterida: Xyalidae) from the Yellow Sea, China

Abstract

Two new species of free-living marine nematode, Pseudosteineria sinica sp. nov. and Pseudosteineria zhangi sp. nov., from the Yellow Sea, China are described. Pseudosteineria sinica sp. nov. is characterized by body spindle-shaped, cuticle distinctly annulated; amphidial fovea not visible; spicules unequal in length, the longer one divided into two sections jointed in the middle, the shorter one simple, without indentation; both spicules curved with proximal capitulum, tapered distally; gubernaculum with a dorso-caudal apophysis. Pseudosteineria zhangi sp. nov. is characterized by eight groups of relatively short subcephalic setae; amphidial fovea circular, lying at level of grouped subcephalic setae; spicules paired, equal in length, dissimilar in shape; right spicule slender, left one with a large manubrium proximally; gubernaculum bucket-shaped, with a dorsal apophysis. A key to species is provided for the 13 valid species of the genus.