SHORT COMMUNICATION Morphology and histopathology of Calyptospora sp. (Apicomplexa: Calyptosporidae) in speckled peacock bass, Cichla temensis Humboldt, 1821 (Perciformes: Cichlidae), from the Marajó-Açu River, Marajó Island, Brazil Hérika Santiago & José Luís Corrêa & Rogerio Tortelly & Rodrigo Caldas Menezes & Patrícia Matos & Edilson Matos Received: 10 October 2011 /Accepted: 6 December 2011 /Published online: 27 December 2011 # Springer-Verlag 2011 Abstract Several species of coccidia are protozoan parasites that cause infection in a wide variety of animal groups. Calyp- tospora is an important genus of protozoan, which infests both freshwater and marine fish. The hepatopancreases of 150 speckled peacock bass captured on Marajó Island, Brazil were studied macro- and microscopically. Oocysts were found in 84 (56%) of the specimens in both the examination of the fresh material by compression and the analysis of histological sec- tions stained with hematoxylin–eosin. Small, circular, homo- geneous forms in negative contrast had a mean diameter of 21.2 μm, frequently with pyriform sporocysts, with a mean length of 9.2 μm and width of 3.1 μm, and a thin-walled capsule, were observed in both the hepatic and the pancreatic parenchyma, but were completely devoid of any inflammatory reaction. Calyptospora infections are documented for the first time in the Marajó-Açu River. Marajó Island is the world’ s largest fluvial island, with an area of approximately 40,100 km², located in the mouth of the Amazon River in the Brazilian state of Pará. The Apicom- plexa occur in a wide range of animals—from helminths to mammals—and represent a prominent potential source of economic loss, principally in birds and animals. Coccidia are common in both marine and freshwater fish (Davies and Ball 1993; Molnar 2006). Species of the genera Eimeria Schneider, 1875; Epieimeria Dykova and Lom, 1981; Goussia Labbe 1896; and Calyptospora Overstreet, Hawkins and Fournié, 1984 have been found parasitizing freshwater fish (Azevedo et al. 1993; Bekesi and Molnar 1991). Of the five species attributed to the genus Calyptospora sp., only Calyptospora serrasalmi Cheung et al. 1986, Calyptospora tucunarensis Bekesi and Molnar 1991, and Calyptospora spinosa Azevedo et al. 1993 have been recorded infecting Brazilian fish, primarily the hepatocytes H. Santiago Programa de Pós-Graduação em Biologia de Agentes Infecciosos e Parasitários, Instituto de Ciências Biológicas da Universidade Federal do Pará, Belem, Brazil J. L. Corrêa Prefeitura Municipal de Ponta de Pedras, Ilha de Marajó, Pará, Brazil R. Tortelly Departamento de Patologia Clínica, Faculdade de Veterinária da Universidade Federal Fluminense, Niterói, Brazil R. C. Menezes Laboratório de Pesquisa Clínica em Dermatozoonoses em Animais Domésticos, Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz, Rio de Jainero, Brazil P. Matos Núcleo de Laboratórios “Prof. Dr. Edilson Matos” Instituto de Ciências Biológicas da Universidade Federal do Pará, Belem, Brazil H. Santiago (*) : E. Matos Laboratório de Pesquisa Carlos Azevedo, Instituto da Saúde e Produção Animal da Universidade Federal Rural da Amazônia, Avenida Presidente Tancredo Neves, 2501, Montese 66, 077-530 Belem, Pará, Brazil e-mail: herika_santiago@hotmail.com Parasitol Res (2012) 110:2569–2572 DOI 10.1007/s00436-011-2770-0