Parasitism of Amblyomma variegatum by a Hymenopteran Parasitoid in the Laboratory, and Some Aspects of Its Basic Biology

Unfed Amblyomma variegatum F. nymphs were experimentally infected in the laboratory with a hymenopteran parasitoid, Ixodiphagus hookeri (Howard). The parasitoid was originally obtained from ticks collected from cattle in the Trans-Mara area of Kenya where it naturally infects 50% of A. variegatum nymphs. In the field, nymphs collected from cattle were found to be infected, but not those collected from grass. The optimum temperature for emergence of parasitoids from the nymphs in the laboratory was 28°C, but emerged parasitoids were more active and survived longer at 22°C. There was a higher proportion of parasitoid nonemergence from laboratory-infected than from the field-infected nymphs. This study is the first record of infection of A. variegatum in the laboratory with a parasitoid. Possibilities of mass rearing and use of the parasitoid as a biocontrol agent for ticks are discussed.