RESUMEN
Ecological studies on sandflies were conducted in the Borkhar rural district, north of Isfahan in central Iran from March 1991 to March 1992. Sandflies were collected once every ten days from human dwellings and cattlesheds using sticky (oiled) paper traps. A total of 29004 sandflies were collected and seven species were identified. Phlebotomus papatasi predominated (83.8% in bedrooms and stables and 42.6% in rodent burrows) in the area. The average indoor resting density of P. papatasi ranged from 0.6 (October 1991) to 62.8 per 10 traps (August 1991). The average outdoor resting density of this species varied between 0.7-141.2 per 10 traps in November and July respectively in 1991. The activity of sandflies extended from end May to mid November. There were two peaks in the density curve of most species, one in June or July and the second in August or September. A significant positive correlation was observed between rainfall and relative density. Natural leptomonad infection was found in P. papatasi, P. caucasicus and P. ansarii, P. papatasi is the main vector to man, but P. caucasicus, P. mongolensis, P. ansarii and P. papatasi act as vectors among gerbils.