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During a survey for entomopathogenic nematodes in northern China, a new species of Steinernema was isolated from soil samples collected from Xinhin county, Liaoning province. This nematode was obtained by the insect-baiting technique using last instar larvae of Gallería mellonella. It is described herein as S. xinbinense n. sp. The nematode can be separated from other described species of the group by morphological and morphometric characteristics of the different stages and by characterisation and phylogeny of DNA sequences of the D2D3 domain of the LSU or ITS regions of rDNA. This new species is characterised by the following morphological characters: infective third-stage juvenile with a body length of 694 (635-744) pm, distance from head to excretory pore of 51 (46-53) μm, tail length of 73 (61-81) μzm, E = 71 (65-78)%, presence of eight unevenly spaced and developed ridges in middle lateral field (i.e., nine lines). First generation male with well curved, yellowish spicules 56 (49-62) μm long and gubernaculum 35 (30-41) μm long, small mucron mostly present, first generation female with protruding vulva, tail conical with one or two small muerons and D = 45 (41-50)%. Cross hybridisation tests with S. tielingense, S. kraussei, S.feltiae and S. hebeiense showed that this species was reproductively solated. The analyses of ITS-rDNA and D2D3 sequence confirm that the studied nematode isolate is a valid new species belonging to the 'feltiae-kraussei-oregonense' group. [ABSTRACT FROM AUTHOR]

A new species of Steinernema was isolated from shrub soils in Liaoning province during a survey for entomopathogenic nematodes in north China. This nematode was obtained by the insect-baiting technique using last instar larvae of Galleria mellonella (Lepidoptera: Pyralidae). This new species is described herein as S. tielingense n. sp. It belongs to the 'feltiae-kraussei-oregonense' group and is characterised by infective third-stage juvenile (IJ) with a body length of 915 (824-979) μm, distance from head to excretory pore of 69 (64-73) μm, tail length of 81 (74-85) μm, ratio E=88 (85-94)%, lateral field with eight ridges at mid-body, first generation male spicule 88 (79-98) μm and gubernaculum 61 (49-70) μm long, and first generation female with a vulval protrusion and ratio D=41 (32-49)%. The new species distinctly differs from the related species S. kraussei, S. silvaticum, S. oregonense and S. cholashanense in the different number of ridges in the lateral fields and hyaline tail length as % of total tail length of IJ and male body length and distance from head to excretory pore. Cross hybridisation tests showed that these species were reproductively isolated. The sequences analyses of the internal transcribed spacers (ITS) and D2-D3 regions of the ribosomal DNA confirm this to be a new species. [ABSTRACT FROM AUTHOR]

Highlights: [•] Virulence of EPN isolates against Bradysia odoriphaga differs between isolates. [•] Heat tolerance (40°C, 2h) differs between EPN species. [•] Cold tolerance (−5°C, 8h) differs between EPN species. [•] Survival of heat or cold-treated EPN is affected by time and IJ concentration. [•] Desiccation tolerance (25% glycerol, 25°C, 72h) differs between EPN species. [ABSTRACT FROM AUTHOR]