ECOLOGICAL FACTORS INFLUENCING BURROW LOCATION, GROUP-SIZE AND MORTALITY IN A NOCTURNAL FOSSORIAL KALAHARI DETRITIVORE, PARASTIZOPUS ARMATICEPS PERINGUEY (COLEOPTERA, TENEBRIONIDAE)

Parastizopus armaticeps, a nocturnal detritivorous tenebrionid associa ted with its major foodplant Lebeckia in the southern Kalahari, forms aggregations in burrows around this bush at all dune elevations. Both sexes migrate downslope after rain to breed, especially females from h igher dune elevations, but not all beetles are reproductively active s imultaneously. During drought, beetles inhabit deeper burrows located downslope in shaded areas and form larger groups. Mortality is highest during drought amongst beetles in shallow burrows. The importance of burrow selection for thermoregulation and associated evaporative water loss are discussed.