Infection with spp. in (Siluriformes, Doradidae), in southwestern Amazon, Brazil.

is a hemoflagellate capable of infecting a wide variety of invertebrates and vertebrates, such as Neotropical freshwater fish. The present study described and morphologically compared spp., found in , Valenciennes, 1840, in southwestern Amazon. Fish specimens were sampled in Ipixuna and Juruá rivers located in the states of Amazonas and Acre, Brazil. Fish blood samples were taken by cardiac puncture, and smears were prepared for quantification, morphometric measurements, and morphotyping (characterization of the trypanosomes according to their morphological variations) of trypanosomes found. Prevalence, mean abundance, and intensity of parasitism were estimated in the parasitized fish specimens. Five fish specimens were collected, showing a 100% prevalence of parasites in the host. We found two morphotypes, A and B, in which A had the highest infection intensity in host specimens. Thus, the present study presented the first report of parasitizing , with different morphological variations.