TASTE STIMULI FOR TSETSE-FLIES ON THE HUMAN SKIN

The adequate stimuli for taste receptors on the legs of tsetse flies ( Glossina spp.) have hitherto been unknown. Here we present electrophys iological evidence that for Glossina fuscipes fuscipes human sweat-man is one of the flies' hosts-is an adequate stimulus. The receptor cell s which respond to human sweat are located in two sensilla proximal to the base of the empodium at the distal end of the fifth tarsomere. Th e receptors are sensitive to four of the 14 major components of sweat tested: uric acid, leucine, valine and lactic acid. We show that flies display more feeding behaviour on surfaces treated with sweat, uric a cid, leucine or valine than on untreated surfaces.