Steinernema nguyeni n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from South Africa

Abstract

Steinernema nguyeni n. sp. was recovered by baiting from beneath an Olea africana tree in South Africa. The combination of morphological and molecular features suggests that S. nguyeni n. sp. is a member of the feltiae-kraussei-oregonense group, clustering with members of this group in Clade III. The new species is morphologically characterised by the infective juvenile body length of 737 (673-796) μm and the number of ridges in the infective juvenile lateral field is 2, 8, 2. The male of the first generation can be recognised by the spicule length of 66 (58-75) μm and a gubernaculum length of 43 (30-55) μm. The first generation female can be recognised by the vulval lips only slightly protruding and the presence of low, double-flapped epiptygmata. Analysis of the ITS and D2-D3 regions of the ribosomal DNA confirms that S. nguyeni n. sp. differs from all other known Steinernema species