the activities were performed at a preserved forest named "cap？o da imbuia", in the urban area of curitiba, paraná, brazil, during march/1990 till march march/1991. the tree holes studied, showed different features: soil distance, area and volume. 303 immatures forms from seven specie of culicidae were caught: haemagogus (conopostegus) leucocelaenus (dyar & shannon, 1924), culex (culex) acharistus root, 1927, toxorhynchites (lynchiella) theobaldi (dyar & knab, 1906), culex (culex) eduardoi casal & garcia, 1968, culex (culex) quinque-fasciatus say, 1823, aedes (protomacleaya) terrens (walker, 1856). two species were the most frequent: haemagogus (c.) leucocelaenus and toxorhynchites (l.) theobaldi, both of them had the higlest medias during spring and summer. these species were in overposition during the caughts.