Bruno P. Berto

Isospora sepetibensis Berto, Flausino, Luz, Ferreira and Lopes, 2008 is a protozoan coccidian parasite (Chromista: Miozoa: Coccidiomorphea: Coccidia) that was originally described from Brazilian tanagers Ramphocelus bresilius (Linnaeus, 1766) in the Marambaia Island in the Coast of the State of Rio de Janeiro. In the current  work, this species was identified from black-goggled tanagers Trichothraupis melanops (Vieillot, 1818) in the Itatiaia National Park, which is a protected area with a high degree of vulnerability in the interior of the State of Rio de Janeiro, distant in more than 100 km of the type-locality. Its oocysts are sub-spherical to elongate  ovoidal, 25.9 × 20.7 μm with smooth, bi-layered wall, ~ 1.3 μm and length/width ratio of 1.1–1.4 (1.26). Micropyle and oocyst residuum absent, but one or two polar granules are present. Sporocysts are ellipsoidal, 16.8 × 10.3 μm, with both Stieda and sub-Stieda bodies. Sporocyst residuum present  and sporozoites with refractile body and nucleus. Molecular analysis was conducted at the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This new isolate exhibited similarity greater than 98% with Isospora spp. isolates from other Neotropical passerines and with an Isospora sp. pseudoparasite of voles of Eurasia. This is the first coccidian  parasite from a New World tanager to have a molecular identification of the cox1 gene.

Coccidiosis in Guinea pigs (Cavia porcellus) has been frequently associated with the presence ofEimeria caviae; however, this coccidium has never been characterized in detail. This study aimed to present the phenotypic and genotypic characterization of E. caviae from guinea pigs reared under rustic breeding conditions in Brazil. Eimeria caviae oocysts are polymorphic, being sub-spherical, ovoidal or ellipsoidal, 20.9 × 17.7 µm, with a smooth or slightly rough and bi-layered wall, ~ 1.0 µm. Micropyle and oocyst residuum are absent, but one polar granule is present. Sporocysts are ellipsoidal, 10.8 × 6.4 µm. Stieda and parastieda bodies are present, sporocyst residuum is present and sporozoites posses a refractile body and a nucleus. Linear regressions and histograms were performed and confirmed the polymorphism of the oocysts. The internal transcribed spacer 1 of the ribosomal RNA gene (ITS-1 rRNA) of the isolates was sequenced and showed no significant similarity to the orthologous region of other Eimeria species.

This current study reports a new isosporoid (Apicomplexa: Eimeriidae) species parasitizing tropical mockingbirds Mimus gilvus recovered from illegal trade in Brazil. Isospora mimusi n. sp. oocysts are spherical to sub-spherical, 20.6 × 19.6 μm, with smooth, bilayered wall, ~1.2 μm. Micropyle, oocyst residuum and polar granule are absent. Sporocysts are ovoidal, 13.4 × 9.8 μm. Stieda and substieda bodies are present. Sporocyst residuum composed of diffuse granules of various sizes, sporozoites have one refractile body.