PARASITISM BY CUTEREBRID BOTFLIES (METACUTEREBRA-APICALIS) IN ORYZOMYS-NITIDUS (RODENTIA, CRICETIDAE) AND METACHIRUS-NUDICAUDATUS (MARSUPIALIA, DIDELPHIDAE) IN A SOUTHEASTERN BRAZILIAN RAIN-FOREST

Parasitism by botflies, Metacuterebra apicalis (Diptera: Cuterebridae), was assessed in natural populations of Oryzomys nitidus (Rodentia: Cricetidae) and Metachirus nudicaudatus (Marsupialia: Didelphidae) in Sao Paulo State, Brazil. Mammals were trapped from February 1989 to March 1990. Prevalence varied seasonally in the 2 host populations, peaking in January 1990 during the rainy season. Mean intensity was 1.3 bots per host (range 1-3) in O. nitidus and 1 bot per host in M. nudicaudatus. Warbles developed on the lateral thoracic region and neck of O. nitidus and on the neck and above the eyes of M. nudicaudatus. Infection levels did not differ significantly between sexes in either host. This is the first record of M. nudicaudatus and O. nitidus as hosts of cuterebrid botflies.