Abstract: Entomopathogenic nematodes in the families Steinernematidae and Heterorhabditidae are potential biological control agents against pest insects, of which Steinernematidae is represented by the genera Steinernema and Neosteinernema, and Heterorhabditidae by the genus Heterorhabditis. Over the past decade, new technologies (especially molecular methods) have been incorporated into the traditional morphological approaches in identification and diagnosis of entomopathogenic nematodes. The entomopathogenic nematode systematics has come into a phase of stability and growth. More and more newly discovered nematode species/isolates have been used into the biological control of pests. At present, there are 65 recognized named species of entomopathogenic nematodes in the two families, with 52 species in Steinernema, 1 species in Neosteinernema and 12 species in Heterorhabditis. This paper lists the species of entomopathogenic nematodes and their sources, and reviews the advance in the taxonomic status and the taxonomic techniques of entomopathogenic nematodes, with emphasis on the molecular methods.

Key words: Entomopathogenic nematodes, classification, identification, molecular methods