The objective of the present study was to determine the index of synanthropy of adults of Muscidae species collected in Valdivia, Chile (39°48'S; 73°15'W). The flies were collected monthly between September 1996 and August 1997 at three different locations, representing urban, rural and natural environments. Rat carcasses, chicken viscera, and fish viscera were used as bait. Six species of Muscidae were collected: Psilochaeta chalybea (Wiedemann) was dominant in urban and rural habitats, being eusynanthropic. The second species in importance was Hydrotaea acuta (Stein), being hemisynanthropic and more abundant in the natural environment. Ophyra ignava (Harris) was another species captured in relatively large numbers, and showing eusynanthropic characteristic. The remaining three species, Musca domestica L., Palpibracus valdiviensis (Couri & Pamplona), and Mu scina stabulans (Fallén) were captured in low numbers. In addition to the indexes of synanthropy, monthly abundances were determined and discussed, as well as the efficiency of the different baits used to collect the flies. The medical and sanitary importance of the flies was also assessed.
Psilochaeta chalybea; Hydrotaea acuta; Ophyra ignava; urban fly; synanthropic index
