SEASONAL DEVELOPMENT OF GRYLLOTALPA AFRICANA(ORTHOPTERA: GRYLLOTALPIDAE) ON TURFGRASS IN SOUTH AFRICA

The population dynamics (in terms of seasonal development) of Gryllotalpa africana Palisot de Beauvois was documented for the first time in South Africa. An irritant drench (soapy water solution) was used to quantify life stage occurrence on turfgrass over a one-year period. Oviposition took place from early October (spring), with eggs incubating for approximately three weeks. Nymphs reached the adult stage from March (late summer) and most individuals overwintered in this stage. Adult numbers peaked in early September (early spring), declining through spring. G. africana was therefore univoltine in the study area. The adult population was female biased in spring. The smallest nymphs and adults (in relation to mean length) were collected in December (early summer), while the smallest nymphs (in relation to mean length) occurred in November (late spring).