Isospora geospizae,a new coccidian parasite (Apicomplexa: Eimeriidae) from the small ground finch (Geospiza fuliginosa) and the medium ground finch (Geospiza fortis) from the Galapagos Islands

Isospora geospizae n. sp. is described from the faeces of the small ground finch Geospiza fuliginosa and the medium ground finch Geospiza fortis from Santa Cruz Island in the Galapagos archipelago. I. geospizae oocysts are spherical to subspherical, with a one-layered, smooth, colourless wall, 15.5×14.5 (13–17×12–17) m with a large polar body and no micropyle or residuum. Sporocysts are ovoid, 10×7.5 (10–12×6–9) m with small Stieda and subtieda bodies and a smoothly contoured, but irregular-shaped residuum containing coarse, non-uniform granules. Sporozoites are sausage-shaped with large refractile bodies at each end and randomly arranged in the sporocysts. Three of 34 (8.8%) G. fuliginosa and one of nine (11.1%) G. fortis were infected with I. geospizae.