Thirteen types of Trematoda larvae (eight with simple tail, designed S1 to S8, and five with forked tail designed as B1, B4, B5, B8 and B9), arising from freshwater molluscs collected in the hidrographic basin of Soledade lake, municipality of Ouro Branco, Minas Gerais state, Brazil are characterized. Xiphidiocercaria S1 presented a Specific Cercarial Index (ICE) of 66.6% and emerged from Biomphalaria glabrata; Xiphidiocercaria S2 with ICE of 96.7% emerged from Physa marmorata; Echinostome cercariae S3, with ICE of 71,6% (the most frequent), S5 with ICE of 7.5%, and Gymnocephala cercaria S4 with ICE of 1.7% emerged from B. tenagophila. Gymnocephalous cercariae S6, with ICE of 0.4%, and S8, with ICE of 16.6%, emerged mainly during the night from B. tenagophila and B. glabrata respectively. The larvae characterized as Echinostome cercaria S7 were found in B. tenagophila and Lymnaea columella and presented an ICE of 8.4% and 84.6% respectively. The forked-tailed larvae Strigeocercariae B1, with ICE of 0,1%, B4, with ICE of 0.9%, and B9, with ICE of 2.7%, all emerged from B. tenagophila. Strigeocercaria B5 was observed in B. tenagophila, B. glabrata, P. marmorata and L. columella and presented ICEs of 3,2%, 16.6%, 3.3% and 17.4% respectively. Cercaria Ocelífera B8 emerged from B. tenagophila and presented an ICE of 3,3%.
Keywords: Cercaria, Trematoda, Biomphalaria glabrata, B. tenagophila, Lymnaea columella, Physa marmorata, Freshwater molluscs.