Calyptospora sp. in Brachyplatystoma vaillantii trapped at the Vigia, State of Pará, Brazil.

The article describes the first occurrence of hepatic coccidiosis in catfish of the species Brachyplatystoma vaillantii, captured in the coastal region of the Vigia city, state of Pará, Brazil, caused by species of the genus Calyptospora, family Calyptosporidae. Thirty specimens of piramutabas were examined where 60% were infected with liver location, featuring numerous mature and immature oocysts, grouped or isolated, with four sporocysts in pyriform shape. They were described on their morphology and dimensions of the oocysts and sporocysts, obtained from light microscopy and differential interference contrast.