RESUMEN
Nyssomyia whitmani (Antunes & Coutinho) is the sandfly vector of causative agents of American cutaneous leishmaniasis in South and Central America. It is widely spread throughout Brazil, in a close association with domestic animals. Almost nothing is known about male mating aggregations in N. whitmani, let alone the influence of moonlight on this behavior. Thus, the influence of moonlight on male N. whitmani aggregations was investigated by using non-attractant suction traps deployed in chicken cages under full moon and new moon nights. In this 18-night study, 2,160 specimens and seven species were collected. The most frequent species was N. whitmani accounting for 91.48% of the total sample. The abundance of males of N. whitmani was significantly higher in the presence than in the absence of moon. The sex ratio on new moon nights was 1:1 (M:F) and on full moon nights was male-biased (1.7:1). Based on this study, an influence of moonlight on male mating aggregations of N. whitmani was verified. The extent of this influence on increasing sandfly aggregation at hosts, the moonlight influence on the early flight activity of male sandflies and the use of chickens as aggregation sites for males of N. whitmani, are all discussed.