The use by wasps, bees and spiders of shells of Trigonephrus Pilsb. (Mollusca: Gasteropoda: Dorcasiidae) in desertic winter-rainfall areas in southern Africa

The use of snail shells in desertic areas in the winter-rainfall region of southern Africa was investigated. Principal users are: spiders constructing silk-bag nests; megachilid-bees, species of Wainia (Wainia) (Osmiini), Hoplitis (Anthocopa) (Osmiini) and Afranthidium (Oranthidium) (Anthidiini), and a eumenine-wasp constructing nests within empty shells utilizing nesting materials brought in; and two masarine-wasps, Quartinia spp., excavating nesting burrows stabilized with self-generated silk in sand-filled shells. Species of Allocoelia (Chrysididae),Tricholabiodes (Mutillidae) and Apolysis (Bombyliidae) were reared from Quartinia nests. Notable is the use of sand-filled shells as stable nest sites in wind-swept deserts.