Caryospora maxima sp. n. (Apicomplexa: Eimeriidae), new coccidium from Forskal’s sand snake, Psammophis schokari (Serpentes: Colubridae) from lava desert of Jordan

A new coccidian parasite of the genus Caryospora Léger, 1904 is described from the colubrid snake Psammophis schokari (Forskål, 1775). Oocysts of Caryospora maxima sp. n. are spherical or subspherical, 43.0 (40.0-46.0) × 42.1 (40.0-44.0) μm, with smooth and bilayered oocyst wall ca. 2.0 μm thick. A micropyle, oocyst residuum and polar granule are absent. Sporocysts are broadly ellipsoidal, 21.3 (21.0-22.0) × 16.3 (16.0-17.0) μm, with smooth, colourless and unilayered sporocyst wall. Stieda and substieda bodies are present. Sporocyst residuum is present as compact mass of granules lying centrally between sporozoites. Sporozoites are elongate, arranged head to tail within sporocyst. Caryospora maxima represents the first coccidian species described from Psammophis schokari. Forskal’s sand snake, Psammophis schokari (Forskål, 1775) is a widely distributed colubrid snake species, occurring in desert and semidesert ecosystems of Sahara and sub-Saharan regions of Africa, in the Near and Middle East, India and republics of the former USSR. No species of coccidium has been described from this species of snake to date. In this paper a species of the genus Caryospora is reported for the first time from Psammophis schokari and is described as a new species. MATERIALS AND METHODS Three adult specimens of Psammophis schokari were captured alive during field parasitological and herpetological research in Jordan in April 1996. Collected snakes (one specimen from locality Safawi, 32°12’N; 37°10’E, and two specimens from locality Zoubia 32°25’N; 35°45’E) were placed individually in plastic cages and transported into the Czech Republic. Snakes were housed individually in 15-litre plastic cages in an isolated room at 22-25°C during daytime and 17-20°C during the night. The floor of the cages was covered with paper towels and locally heated by heating pad to 27°C during the day. The snakes were force-fed on juvenile laboratory mice. Individual faecal samples were repeatedly collected from cages and from grounds of the terraria and were examined microscopically after concentration by flotation with modified Sheather’s sugar solution (s.g. 1.30). Oocysts were then measured and photographed using Nomarski interference contrast (NIC) optics. Measurements were made using a calibrated ocular micrometer and are reported in micrometres as means, followed by the ranges in parentheses. One specimen of Psammophis schokari from Safawi was euthanised by overdose of barbiturate (Thiopental, Spofa, Czech Republic) and necropsied. Tissue samples of stomach, small and large intestine, heart, lung, liver, gall bladder and kidneys were fixed in 10% buffered formalin and processed for light microscopy using standard histological method. Paraffin sections were stained with haematoxylin and eosin (H&E) and Giemsa stains.