Isospora vanriperorum from the green-winged saltator (Saltator similis) is described in Southeastern Brazil. Oocysts are spherical to subspherical, 19.4-26 by 18.3-26 micro (23.1 by 22.4 micro), shape index 1.04 with a single layered wall, fine, smooth and yellowish. Micropyle and residuum are absents, but one elliptical polar granule is present. Sporocysts are ovoid, 14.5-20.2 by 8.1-12.5 micro (16.3 by 10.8 micro), shape index 1.53 with prominent Stieda body, barely discernible substieda body and residuum centered and granulated.