Characterization of a new species of entomopathogenic nematodes Oscheius sp. (Nematoda, Rhabditidae) from Georgia (Caucasus)

Surveys in the village of Shamgona in Samegrelo Region of West Georgia, a new nematode species belonging to Oscheius genus was isolated from soil of hazelnut orchard. Leptoderan bursa and spicules with hook-like endings are the main characters for assigning the new species to Insectivora group. The new Oscheius sp. is closely related to O. colombiana, O. carolinensis, O. myriophila, and O. rugaensis at morphological level. The most prominent distinctive morphological feature is the presence of eight lateral lines. The female has the largest body and widest body size, respectively, 1816 (1591-2329) µm and 136 (106-143) µm compared with other Oscheius spp. Spicule sizes of males and values of coefficients a and c are also different. Entomopathogenecity tests were carried out on Galleria mellonella and Tenebrio molitor. Molecular analyses were carried out by amplifying ITS, D2-D3 expansion domains and mitochondrial COI as markers. BLAST Search at NCBI revealed no corresponding sequences.