Influence of Moonlight on Male Mating Aggregations of Nyssomyia whitmani, a Vector of American Cutaneous Leishmaniasis in Brazil.

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.

Exploiting the Synergistic Effect of Kairomones and Light-Emitting Diodes on the Attraction of Phlebotomine Sand Flies to Light Traps in Brazil.

The synergistic effect of light-emitting diodes (LEDs) and kairomones on the attraction of sand flies to light traps was evaluated. Octenol and lactic acid were used as chemical attractants. Green LEDs and the incandescent lamps were used as light attractants. Five CDC-type light traps with the respective combination of attractants (incandescent lamp, incandescent lamp + chemical attractant, green LED, green LED + chemical attractant, and chemical attractant alone [without light]) were set between 18:00 and 06:00 following a Latin square design. A total of 6,536 sand flies and 16 species were collected. The most frequent species collected was Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera, Psychodidae) accounting for 43.21% of all individuals. Order of success (mean, SD) of lactic acid attractant fly capture was as follows: LED + lactic acid (36.83 ± 4.74), LED alone (34.87 ± 4.61), incandescent lamp + lactic acid (22.80 ± 3.19), incandescent lamp alone (12.67 ± 2.03), and lactic acid (0.46 ± 0.13). Order of success of octenol attractant fly capture was as follows: LED + octenol (37.23 ± 5.61), LED alone (35.77 ± 5.69), incandescent lamp + octenol (18.63 ± 3.28), incandescent lamp alone (14.67 ± 2.86), and octenol alone (1.80 ± 0.65). With exception of lactic acid + incandescent light, chemical synergists played no part in significantly increasing light trap capture of phlebotomine sand flies. However, the use of LEDs, with or without such attractants, provided significantly higher capture compared to the incandescent lamp with or without such chemicals, showing that LEDs are suitable and efficient light sources for surveillance and monitoring of phlebotomine sand flies in Brazil.

Field performance of a low cost, simple-to-build, non-motorized light-emitting diode (LED) trap for capturing adult Anopheles mosquitoes (Diptera: Culicidae).

In this paper, a non-powered trap equipped with light-emitting diodes (LEDs) designed for capturing small night-flying insects was field-evaluated for sampling anopheline mosquitoes. This new light trap, referred to as the Silva trap, was compared with the Centers for Disease Control and Prevention (CDC) miniature light trap in a livestock area in northeastern Brazil. Light traps were operated from 18:00 to 06:00 between July and August 2018, over a 12-night period. A total of 3124 specimens and eight species were collected. Anopheles (Nyssorhynchus) argyritarsis was the prevalent species, followed by A. (Nys) triannulatus s.l., A. (Nys) goeldii, A. (Nys) evansae, A. (Nys) rangeli, A. (Nys) galvaoi, A. (Nys) darlingi and A. (Nys) albitarsis s.l. The total number of anopheline mosquitoes captured with the Silva trap was higher than the number of individuals captured with the CDC light trap, but no significant difference between the two trapping methods was found. Concerning the damaged specimens, the Silva trap damaged significantly less mosquitoes than the CDC light trap. According to these results, the Silva trap has acceptable performance in being an efficient tool for sampling anopheline mosquitoes, mainly in comparison with the CDC light trap. The Silva trap has a number of advantages over other trapping devices that collect questing mosquitoes and these advantages are pointed out and discussed.