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In 2021/2022, galls formed by a nematode, Anguina woodi, were found on the stems, leaves and leaf sheaths of dune grass, Ehrharta villosa var. villosa on Milnerton Beach, Blouberg Beach and Langebaan, Western Cape Province, South Africa. These galls were spongy in texture, deep purple to blackish in colour and non-pedunculate. They were found in clusters, but also as single entities. Larger, harder galls varying from beige to dark brown in colour, apparently caused by insects, were also found on the stems of dune grass at Blouberg Beach and Langebaan Nature Reserve. Some nematode galls were found immediately next to or on top of the insect galls. Those found on top of insect galls seemed to be harder and drier than those found on stems not infected by insect galls. The co-infection of insects and anguinid nematodes has not been reported from the current study areas and was thus included in the present study. Both molecular and morphological studies were conducted on the nematodes and wasps leading to the identification of a host specific, gall-forming nematode from all three localities. The wasps were identified morphologically and molecularly to the family Eurytomidae (Hymenoptera). No insect galls were found on dune grass from Milnerton Beach. The paper includes speculations on a probable association between nematodes and insects. [ABSTRACT FROM AUTHOR]

Phlyctinus callosus and P. xerophilus (Coleoptera: Curculionidae) are two cryptic species of native entimine weevils, previously grouped together under the P. callosus sensu lato concept, that are pests of economic importance to the deciduous fruit and vine industry in the Western Cape province of South Africa. Laboratory bioassays were conducted using entomopathogenic fungi (EPF) isolates of Beauveria and entomopathogenic nematodes (EPNs), Heterorhabditis indica and Steinernema yirgalemense, to determine differences in susceptibility of adult P. callosus and P. xerophilus to potential biological control agents. The test arena used was 24‐well bioassay plates with an inoculation rate of 200 infective juveniles (IJs)/insect for EPNs and 5 × 105 conidia/insect for EPF. Insects were inoculated using a 12.7 mm filter paper impregnated with 50 μL of entomopathogen suspension. Infection was determined after 96 h incubation for EPNs through dissection of cadavers. Insects inoculated with EPF were incubated in the wells for 18 days and mortality recorded daily. Cadavers were surface sterilized and observed for overt mycosis. Differential susceptibility between P. callosus and P. xerophilus was observed in EPF but not in EPN bioassays. Differential susceptibility to EPF could be due to methodology. Low adult weevil pathogenicity was found for all entomopathogens, with variable results obtained from different bioassay batches. [ABSTRACT FROM AUTHOR]