Three new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) infecting the Song Sparrow Melospiza melodia Wilson (Aves: Passeriformes: Passerellidae) in Toluca Valley, Mexico

Abstract Three new isosporan (Apicomplexa: Eimeriidae) species from the song sparrow Melospiza melodia Wilson in Mexico are described in the present study. The sporulated oöcysts of Isospora cantoris n. sp. are subspherical, 19.4−21.5 × 16.9−18.9 (20.5 × 18.0), with a length/width (L/W) radio 1.0−1.2 (1.04), mycropile and oöcyst residuum absent and one compact polar granule present. The sporulated oöcysts of Isospora melodiae n. sp. are spherical to subspherical, 20.2−21.4 × 18.5−19.7 (20.8 × 19.1), with a length/width (L/W) radio 1.0−1.1 (1.05), mycropile and oöcyst residuum absent and one compact polar granule present. The sporulated oöcysts of Isospora villai n. sp. are subspherical, 20.7−23.8 × 19.4−23.3 (22.3 × 21.4), with a length/width (L/W) radio 1.0−1.2 (1.1), mycropile, oöcyst residuum and polar granule absent. In conclusion, I. cantoris , I. melodiae and I. villai are coccidian species new to science, being a total of seven species of the genus described from New World sparrows.