Phasmarhabditis akhaldaba sp. n. associated with a slug Deroceras reticulatum in Lesser Caucasus mountains in Republic of Georgia

A new nematode species, Phasmarhabditis akhaldaba sp. n., was isolated in Borjomi municipality (Republic of Georgia). The species was characterised by the presence of two strains, the first isolated from the slug Deroceras reticulatum and another one from the cadaver of Galleria mellonella larva used as a bait for entomopathogenic nematodes in soil. Strains designated as 'quick' and 'slow' differed in the body lengths of dauer juveniles and the visually different speed of movement during migration. Morphologically, the adult stages are characterised by a head with six low, rounded lips bearing a ring of six labial papillae, four cephalic papillae and pore-like amphids situated on top of lateral lips, males with a moderately wide bursa and spicules 65-67 mu m long lacking holes at the distal tips. Average length of an ensheathed dauer juvenile of P. akhaldaba sp. n. is 862 mu m in the strain 'quick' and 702 mu m in the strain 'slow'. The molecular analysis based on partial sequences of ITS rDNA regions of both strains has shown its identity. Both morphologically and genetically, the new species is close to another species from Caucasus, P. circassica Ivanova, Geraskina & Spiridonov, 2020.