A new entomopathogenic nematode, Steinernema hebeiense sp. n. (Rhabditida: Steinernematidae), from North China

Abstract

AbstractA new species of Steinernema (Rhabditida), S. hebeiense sp. n. was isolated from sandy soil, Hebei Province, China. Diagnostic characters of infective juveniles of S. hebeiense sp. n. include total body length of 658 (610-710) μm, distance from anterior end to excretory pore of 48 (43-51) μm, tail length of 66 (63-71) μm, and E% ratio of 72 (65-80). The lateral field has eight ridges at the mid-body region (two very thin submarginal ridges, poorly discernible under light microscope, but visible in SEM); and the anterior end is slightly offset and flattened. First generation males have a body length of 1177 (1036-1450) μm, spicule length = 57 (51-63) μm, and gubernaculum length = 46 (38-50) μm. The spicules are light brown in colour and slightly curved; the manubrium is longer than wide. A tail mucron is present in second generation males. These morphometrical and morphometric features classify S. hebeiense sp. n. within the ' feltiae-kraussei-oregonense ' group. Molecular data also classify the new species within this group. Within this group, the smallest differences between the sequences of S. hebeiense sp. n. is with S. weiseri – 73 bp in the ITS rDNA and 13 bp in the studied partial sequence of the D2D3 expansion segment of LSU rDNA.