Two new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the flap-necked chameleon Chamaeleo dilepis (Sauria: Chamaeleonidae) in the Republic of Namibia.

Two new species of Isospora Schneider, 1881 from flap-necked chameleons Chamaeleo dilepis Leach are described from the faeces of specimens collected in the Republic of Namibia. Oöcysts of Isospora freedi n. sp. from one of four (25%) C. dilepis collected in the East Caprivi District are spherical to subspherical, with a smooth, colourless, bilayered wall, measure 23.7 × 21.2 μm and have a length/width (L/W) ratio of 1.1. The micropyle and the oöcyst residuum are absent but a polar granule is sometimes present. Sporocysts are ovoidal to ellipsoidal and 13.9 × 10.3 μm in size with prominent Stieda and sub-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Isopora mandelai n. sp. from three of seven (43%) C. dilepis collected in the Outjo District are ellipsoidal to cylindroidal, with a smooth, colourless, bilayered wall, measure 36.9 × 31.0 μm and have an L/W ratio of 1.2. The micropyle, oöcyst residuum and polar granule are absent. Sporocysts are ovoidal to ellipsoidal, 15.3 × 11.1 μm in size and contain Stieda and sub-Stieda bodies; and the non-membranous sporocyst residuum is composed of granules of various sizes. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. These two new taxa represent the third and fourth coccidian species reported from C. dilepis.