Seasonal and Circadian Dynamics


New World

Circadian activity

Mexico: Maximum bite rate of Lu. cruciata in was found between 18:00 and 19:00 hours. Host-seeking females were observed to be directly related to levels of humidity (Rebollar-Tellez et al., 1996).

Colombia: Field studies with Lu. longipalpis revealed increased activity shortly after sunset, continuing until just after sunrise. Furthermore peak sandfly activity was greatest early in the evening (18:30-23:30 hours) and then declined steadily towards morning (Morrison et al., 1995b).

Venezuela, Caribbean coast:
Observing Lu. evansi and Lu. panamensis, maximum landing / biting activity of Lu. evansi was observed at 24:00 and 3:00 hours. For Lu. panamensis maximum landing/biting activity was observed between 2:00 and 03:00 hours (González et al., 1999).

Seasonal activity

Mexico: Population dynamic studies revealed highest peak population for Lu. cruciata in March, and lesser peaks in February, December and January of the study years (Rebollar-Tellez et al., 1996).

Venezuela: Lu. evansi was most abundant in October and July, associated with a bimodal cycle of annual rainfall in the area. Lu. panamensis showed maximal landing / biting activity in June, slightly preceding the annual rainfall maximum in July, and a secondary peak in December, somewhat after the secondary rainfall maximum in October, coinciding with the start of the December-February dry season (González et al., 1999).
In the northern part of the country further seasonal activity of Lu. panamensis was reported by (Feliciangeli, 1987). In their studies the species behaved as a wetseason species with mean minimum relative humidity as critical factor influencing the total number of individuals. Decreasing population numbers were replaced by Lu. ovallesi, a dry-season species.

Colombia: A bimodal annual abundance cycle with a small peak in October-November and a larger peak in April-May (prominent 6-mo cycle) was observed for Lu. longipalpis (Morrison et al., 1995a).
In studies in the northern part of the country, Lu. evansi, the vector of visceral leishmaniosis, was predominant. Generally the sand flies were present throughout the year with exception of the driest months (February and March). Parous and infected sand flies were most abundant towards the end of the rainy season (October-December) (Travi et al. 1996).

USA, Texas: Lu. diabolica had its peak abundance in July in Texas (McHugh et al., 2001).

USA, Georgia: The first appearance Lu. shannoni, was recorded in April. Peaks of abundance followed in May (the one year) and May and July (the following year), again followed by rapid reduction in October and November respectively September and October. No specimens were collected in December respectively March, November and December (Brinson et al., 1992).



  • Brinson, F.J., D.V. Hagan, J.A. Comer and D.A. Strohlein: Seasonal abundance of Lutzomyia shannoni (Diptera: Psychodidae) on Ossabaw Island, Georgia. J. Med. Entomol. 29, 178-182, 1992
  • Feliciangeli, M.D.: Ecology of sandflies (Diptera: Psychodidae) in a restricted focus of cutaneous leishmaniasis in northern Venezuela. III. Seasonal fluctuation. Mem. Inst. Oswaldo Cruz 82, 167-176, 1987
  • González, R., L. De Sousa, R. Devera, A. Jorquera, and E. Ledezma: Seasonal and nocturnal human landing/biting behaviour of Lutzomyia (Lutzomyia) evansi and Lutzomyia (Psychdopygus) panamensis (Diptera: Psychodidae) in a periurban area of a city on the Caribbean coats of eastern Venezuela (Barcelona; Anzoátegui State). Trans. R. Soc. Trop. Med. Hyg. 93, 361-364, 1999
  • McHugh, C.P., B.F. Ostrander, R.W. Raymond, and S.F. Kerr: Population dynamics of sand flies (Diptera: Psychodidae) at two foci of leishmaniasis in Texas. J. Med. Entomol. 38, 268-277, 2001
  • Morrison, A.C., C. Ferro, R. Pardo, M. Torres, B. Devlin, M.L. Wilson and R.B. Tesh: Seasonal abundance of Lutzomyia longipalpis (Diptera: Psychodidae) at an endemic focus of visceral leishmaniasis in Colombia. J. Med. Entomol. 32, 538-548, 1995a
  • Morrison, A.C., C. Ferro, R. Pardo, M. Torres, M.L. Wilson, and R.B. Tesh: Nocturnal activity patterns of Lutzomyia longipalpis (Diptera: Psychodidae) at an endemic focus of visceral leishmaniasis in Colombia. J. Med. Entomol. 32, 605-617, 1995b
  • Rebollar-Tellez, E.A., F. Reyes-Villanueva, I. Fernandez-Salas, and F.J. Andrade-Narvaez: Population dynamics and biting rhythm of the anthropophilic sandfly Lutzomyia cruciata (Diptera: Psychodidae) in Southeast, Mexico. Rev. Inst. Med. Trop. São Paulo 38, 29-33, 1996
  • Travi, B.L., J. Montoya, J. Gallego, C. Jaramillo, R. Llano and I.D. Velez: Bionomics of Lutzomyia evansi (Diptera: Psychodidae) vector of visceral leishmaniasis in northern Columbia. J. Med. Entomol. 33, 278-285, 1996

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