Katumanyane, AgilMalan, Antoinette P.Tiedt, Louwrens R.Hurley, Brett Phillip2020-10-292020-10-292020-02Katumanyane, A., Malan, A.P., Tiedt, L.R. et al. 2020, 'Steinernema bertusi n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from South Africa', Nematology, vol. 22, no. 3, pp. 343-360.1388-5545 (print)1568-5411 (online)10.1163/15685411-00003309http://hdl.handle.net/2263/76647Two isolates of Steinernema bertusi n. sp. were separately recovered from Tito, Mpumalanga, and Port Edward, Kwa Zulu Natal, South Africa. In this paper, we describe the isolates as a new entomopathogenic nematode (EPN) species using molecular and morphological methodologies. The new species belongs to the cameroonense -clade, which consists of nematodes only isolated from the African continent. Steinernema bertusi n. sp. is characterised by having the longest infective juvenile (IJ) for this clade at 716 (628-814) μ m. The IJ is further characterised by a body diam. of 32 (28-36) μ m and the pattern for the arrangement of the lateral ridges from head to tail is 2, 4, 5, 4, 2. The first-generation male spicule and gubernaculum length is 82 (72-88) μ m and 63 (54-72) μ m, respectively. Only 25% of the second-generation males possess a mucron. The first-generation females of S. bertusi n. sp. have a slightly protruding vulva, with double-flapped epiptygmata and a mucron at the posterior end. The new EPN species is most closely related to S. sacchari and is the sixth species to be included in the cameroonense -clade.en© 2020 Koninklijke Brill NV.Entomopathogenic nematode (EPN)Cameroonense-cladeMolecularMorphologyMorphometricsNew speciesPhylogenyTaxonomySteinernema bertusi n. sp.Postprint Article