A malacological survey was carried in the State of Rondônia, Brazil, in order to establish the geographical distribution of aquatic mollusks with special emphasis on the genera Biomphalaria. Eleven counties along the BR-364 highway were studied, totaling 162 limnic ecossistems, of which 77 (48%) were positive for at least one species of mollusk. The following species were found: Gastropoda, Planorbidae: Biomphalaria sp., B. amazônica, B. occidentalis, Drepanotrema anatinum, D. lucidum, D. depressissimum and D. cimex; Physidae: Stenophysa marmorata; Ancylidae: Gundlachia sp.; Thiariidae: Aylacostoma sp.; Ampullariidae: Pomacea sp.; Pelecypoda, Sphaeriidae: Eupera primei and Pisidium sp.. New geographical data are given and the epidemiological importance of these findings are discussed.
Biomphalaria; Planorbidae; Rondônia, Brazil; Schistosomiasis