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SummaryIn a survey of nematode damage in groundnut (Arachis hypogaea) (Fabaceae) production areas in the Vaalharts Irrigation Scheme in the Northern Cape Province of South Africa, a nematode was recovered and initially believed to be a member of the genusRobustodorus,i.e., the species has a characteristic robust stylet with very well-developed teardrop-shaped (garlic bulb-like) basal swellings. The specimens were recovered in large numbers from damaged hulls and kernels of field-collected groundnuts and, after thorough morphological and molecular studies, were subsequently identified asAphelenchoides arachidis. Molecular analysis based on near-full-length small subunit (SSU), internal transcribed spacer (ITS) and D2-D3 expansion segments of the large subunit (LSU) rRNA genes supported the monophyly ofA. arachidis,A. subtenuisandR. megadoruswithin the subfamily Aphelenchoidinae. Based on the typological characters observed in the present study compared with descriptions in the literature, these three species are considered as congeneric,i.e., they share very well-developed basal swellings of the stylet. Accordingly, these twoAphelenchoidesspecies are transferred toRobustodorusasR. arachidisn. comb. andR. subtenuisn. comb. In addition, the male tail characters ofRobustodorusandAphelenchoidesare discussed.

During a survey of soil nematodes in Iran, three species of predatory nematodes, including a new species of the genus Mylonchulus Cobb, 1916 were recovered. Mylonchulus kermaniensis sp. n. is characterised by its body length (1.2-1.4 mm), six rows of rasp-like denticles, the sixth line consisting of four denticles, female tail slightly sigmoid, sharply bent ventrad with digitate posterior portion slightly but clearly bent dorsad, (37-49 μm long, c=27.9-38.9, c'=1.2-1.7) with a terminal opening of spinneret. Two advulval papillae present, one is pre-vulval and the other one is located posterior to vulva. Furthermore, two other mononchid species namely M. cf. hawaiiensis (Cassidy, 1931) Goodey, 1951 and Mononchus truncatus Bastian, 1865 were also recovered from soil in the province of Kerman, Iran, the former representing a new geographical record for Iran. Measurements and illustration are provided for these three species. Molecular study of 18S rDNA region of M. cf. hawaiiensis demonstrated that the Iranian population compared with the nearest populations identified as M. hawaiiensis from Japan, shows 5 to 8 nucleotide differences. In addition, phylogeny of Mylonchulus is discussed and a checklist of the species of Mononchida from Iran is provided.

Summary Hemicriconemoides brachyurus was identified morphologically, using body annuli number (103105), stylet length (49-52 μm), tail conical with small rounded lobe, spermatheca with round sperm, and VL/VB (1.3). Molecular analysis was also undertaken, based on the 18S rDNA region, and the obtained DNA sequence data confirmed the present population from South Africa as Hemicriconemoides. Phylogenetic analysis using the Bayesian inference method places this population close to H. fujianensis from China (MH444620-21; MH444626-28). To the best of our knowledge, this is the first report of the 18S rDNA sequence for H. brachyurus.