A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae) from the snake Philodryas olfersii Lichtenstein (Colubridae) from a coastal habitat in Brazil.

A new coccidian species of the genus Caryospora Léger, 1904 (Protozoa, Apicomplexa, Eimeriidae) is reported from the colubrid snake host Philodryas olfersii Lichtenstein at a coastal area in the State of Rio de Janeiro, south-eastern Brazil. Oöcysts of Caryospora olfersii n. sp. are spherical to sub-spherical, 33.1 × 31.2 μm, with smooth, colourless, three-layered wall, c.1.4; middle layer lightly striated. Micropyle, oöcyst residuum and polar granule are all absent. Sporocysts are ovoid, 22.9 × 17.4 μm on average, with one extremity in the shape of a short neck. Stieda body present, 3.2 × 1.3 μm, sub-Stieda body present, homogeneous, larger than Stieda body, 4.5 × 1.7 μm. Sporozoites are inserted in a bulky sporocyst residuum.