Isospora elmahalensis n. sp. (Apicomplexa, Eimeriidae), a parasite of the white-cheeked bulbul (Pycnonotus leucogenys) in Saudi Arabia

Isospora elmahalensis n. sp. is described from the Saudi Arabian bird, Pycnonotus leucogenys, from the Elmahala valley. Sporulated oocysts of I. elmahalensis were spherical or nearly subspherical, 19.5-22.5 X 18.5-20 (21.34 +/- 0.4 X 19.06 +/- 0.5) microns. Oocysts lacked a micropyle, residuum, and polar granule. Sporocysts were ovoid, 14-17.5 X 7-12 (16.08 +/- 1.05 X 9.9 +/- 1.55) microns, and had a Stieda body and sporocyst residuum, but lacked a substiedal body. Sporozoites were elongated with a clear globule at one end. The host bird belongs to the order Passeriformes.