RESUMO
Isospora bioccai (Cringoli and Quesada 1991) (Protozoa, Apicomplexa, Eimeriidae) is reported and described from captive canaries Serinus canaria forma domestica (Linnaeus 1758) in Mexico. The oöcysts are subspherical, 25.5â¯×â¯23.5⯵m, with smooth, bilayered wall, â¼1.3⯵m thick. Micropyle absent, oöcyst residuum absent, and polar granule present, 4-8 rice-grain-shaped. Sporocysts are ovoidal, 16.7â¯×â¯10.5⯵m. Stieda body knob-like and substieda body trapezoidal of irregular base. Sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. Gamogony was seen in the duodenum. In addition to new locality, this is the first description of I. bioccai from S. canaria.