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isolated instances, but they indicate that perhaps the daily feeding 

 activity of Lu. diabol ica is not as restricted as previously reported. 

 Lindquist (1936) reported the feeding period to be from 2000 hrs to 

 2400 hrs and Endris (1982) reported J_u. diabol ica feeding during all 

 hours of darkness. Williams (1966b), in studies of biting rhythms of 

 ten anthropophil ic sand flies in Belize, found the greatest period of 

 activity was between 0600 and 0659 hrs. After this small burst of 

 activity, the number of flies decreased. He said that the flies were 

 least active between 1400 and 1459 hrs (the hottest part of the day), 

 but that biting activity increased gradually from 1500 hrs onward. 

 Flies were not collected in appreciable numbers, however, until dusk 

 (1800-1859 hrs). He noted that numbers increased still further during 

 the early hours of darkness, reaching the peak of greatest activity 

 between 2100 and 2159 hrs. Thereafter, biting density diminished. 

 Consistent with these later reports, the peak feeding period of Lu . 

 diabol ica in June 1982 was observed between one hour after sunset and 

 midnight (2130 to 2400 hrs). Ki 1 1 ick-Kendrick and Rioux (1981) 

 described similar activity for Phlebotomus ariasi Tonnoir in the 

 Cevennes, France, and said it was probably triggered, at least 

 partially, by the rise in relative humidity as the temperature falls 

 at sunset. Parman (1919) said _Lu. diabol ica would not bite in total 

 darkness or in full moonlight. Although most biting collections in 

 June 1982 were taken in the presence of artificial light, sand flies 

 were also collected in lesser numbers while biting in total darkness, 

 having no apparent difficulty finding their host. They were also 

 observed biting outdoors in full moonlight. 



