Two new species of coccidian parasites are described from African reptiles. Oocysts of Eimeria foulshami sp. n. from the plated lizard Gerrhosaurus major bottegoi Del Prato of Sudan are ellipsoidal, 24.1 × 14.9 (23-26.5 × 14-17.8) µm with a bilayered, colourless oocyst wall and lack polar granules. The ellipsoidal sporocysts average 8.6 × 4.6 (7-10.6 × 4.4-7) µm and possess a prominent, globular, sporocyst residuum. Oocysts of Caryospora regentensis sp. n. from the green mamba Dendroaspis viridis Hallowell of Kenya are spherical to subspherical, 16.8 × 16.4 (16-17.6 × 15-17.2) µm with a bilayered oocyst wall and a single polar granule. The ellipsoidal sporocysts average 13.0 × 10.3 (10.2-14 × 9.2-11) µm and possess a Stieda and substieda body and a prominent globular sporocyst residuum. Oocysts of Caryospora legeri Hoare, 1933 are reported from a hissing sand snake, Psammophis sibilans sibilans L. from Nigeria, representing a new geographical record. The oocysts are slightly larger than the type, but otherwise identical. Caryospora psammophi Bray, 1960 and C. hermae Bray, 1960 from Psammophis sibilans phillipsi, oocysts of which are morphologically similar to and overlap in dimensions with C. legeri Hoare, 1933, are synonymised with the latter species. Eimeria samiae Iskander et Tadros, 1979 is emended to E. samyadeli to reflect the gender of the person the species was named after and because E. sami is preoccupied. In addition to these findings, Eimeria bohemi Modrý, Šlapeta et Koudela, 2000 and oocysts of an unidentified spherical Eimeria sp. are reported from Chamaeleo dilepis dilepis Leach from Cameroon.
A new coccidian parasite of the genus Caryospora Léger, 1904 is described from the colubrid snake Psammophis schokari (Forskâl, 1775). Oocysts of Caryospora maxima sp. n. are spherical or subspherical, 43.0 (40.0-46.0) X 42.1 (40.0-44.0) pm, with smooth and bilayered oocyst wall ca. 2.0 μιη thick. A micropyle, oocyst residuum and polar granule are absent. Sporocysls are broadly ellipsoidal, 21.3 (21.0-22.0) x 16.3 (16.0-17.0) μιη, with smooth, colourless and unilayered sporocyst wall. Sticda and substieda bodies are present. Sporocyst residuum is present as compact mass of granules lying centrally between sporozoites. Sporozoitcs arc elongate, arranged head to tail within sporocyst. Caryospora maxima represents the first coccidian species described from Psammophis schokari.
Parasitological examination of two ornate Nile monitors Varanus ornatus (Daudin, 1803) imported from Benin revealed the presence of a new species of Caryospora. Oocysts of Caryospora varaniornati sp. n. are spherical to slightly subspherical, 12.0 (11-12.5) × 11.5 (11-12) µm, without a micropyle and oocyst residuum, and occasionally possessing one small polar granule. Sporocysts are broadly ellipsoidal, 8.8 (8.5-9.5) × 6.7 (6.5-7) µm; a lentil-like Stieda body is present, ca. 0.5 × 1 µm; substieda body not visible. Experimental infection of a closely related host, Varanus niloticus (L.), did not lead to the oocyst excretion despite the fact that one of the experimentally inoculated monitors was immunosuppressed by dexamethasone. Histological examination did not reveal stages of coccidian development. Therefore, it is possible that C. varaniornati is strictly host specific.
Faecal examination of the long nosed vine snake Ahaetulla nasuta Lacépède, 1789 revealed two species of caryosporan coccidia. The morphology of one species fits well with a description of Caryospora ahaetullae Modrý et Koudela, 1994, the second is a previously undescribed species. Oocysts of Caryospora veselyi sp. n. were spherical, 18.9 (16.5-21.5) pm in diameter, with pitted and brownish oocyst wall about 1.5 pm thick. An irregular polar granule about 2,0 x 1.0 pm was observed in 35% of the oocysts examined. Sporocysts were octozoic, ovoidal to ellipsoidal, 13.7 (13.0-15.5) x 10.3 (9.0-11.0) pm with a shape index 1.3 (1.2-1.4). Stieda and substieda bodies were present. Sporocyst residuum was present as small granules of irregular size scattered among sporozoiles. Both species sporulated within 72 hours. The infected snake did not show clinical signs of disease.
A new coccidian parasite of the genus Eimeria Schneider, 1875 is described from the subterranean African silvery mole-rat Heliophobius argenteocinereus Peters, 1846. Oocysts of Eimeria burdai sp. n. were subspherical to broadly ellipsoidal 17.8 (16-19) x 14.1 (12-15), with ashape index 1.2 (1.1-1.4). Oocyst wall was bilayered, smooth and colourless, approximately 1.0 thick. Outer layer was significantly thicker than inner one. A micropyle and oocyst residuum were absent. One or two ellipsoidal or spherical polar granules were present. Sporocysts were ellipsoidal, 10.8 (9-12) x 6.2 (5-8) with a shape index 1.7 (1.5-1.9). Sporocyst wall was single-layered, thin, smooth and colourless, with small Sticda body at the pointed end. In freshly sporulated oocysts, spherical sporocyst residuum was composed of small granules enclosed by a thin membrane. Sporozoites were elongate, lying length-wise in the long axis of the sporocyst, partially curled around each other, with single large refractile body located posteriorly. Faintly distinguishable nucleus was in the central part of the sporozoite. This eimerian represents the first coccidian species described from subterranean African silvery mole-rat (Rodentia: Bathyergidae).
Coprological examinations of three snowy owls, Nyctea scandiaca (L.) revealed the presence of a coecidium of the genus Eimeria that apparently represents a previously undescribcd species. Oocysts of Eimeria nycteae sp. n. were spherical to subspherical, 23.6 (23-25) x 22.2 (22-23) pm with a shape index 1.1 (1.0-1.1). The oocyst wall was bilayered, smooth - 0.75 pin thick. A polar granule was absent. Sporocysts were ellipsoidal, 18.5 (18-19) x 9.8 (9-10) pm with a shape index 1.9 (1.8-2.1) with Stieda and substieda bodies. A sporocyst residuum was present as small granules scattered among sporozoitcs. The sequence of the sporulation process of this new species is given and illustrated with photomicrographs. Owls examined did not exhibit any signs of alteration of their health status.
Four laboratory-hatched European kestrels Falco tinnunculus L. were fed on laboratory mice and common voles Microtus arvalis Pallas previously inoculated with different doses of sporulated oocysts of Caryospora kutzeri Böer, 1982. Two kestrels that were fed infected mice shed C. kutzeri oocysts 6 days after ingesting murine tissues. To compare direct and indirect transmissions, two of the kestrels were subsequently directly inoculated with 105 sporulated C. kutzeri oocysts and became patent on days 8 and 9 and shed caryosporan oocysts up to day 25 post inoculation. Additionally, four mice were inoculated with 106 oocysts in order to examine mouse tissues for the presence of developmental stages of C. kutzeri. No coccidian stages were found in the tissues of inoculated mice. The experiment showed that developmental stages of C. kutzeri are able to survive in mouse tissues and cause infection of suitable host after their ingestion.
Caryospora duszynskii Upton, Current et Barnard, 1984 was successfully transmitted to snakes of the genus Elaphe by feeding them previously infected mice. Fifty thousand oocysts were orally administered to two mouse strains, BALB/c and Crl:CD-1(ICR)BR, which were subsequently fed to captive-born coccidia-free Elaphe guttata (L.) in two respective independent experiments. Both E. guttata expelled C. duszynskii oocysts in their faeces, beginning on day 18 and 26 post infection (p.i.) and shed oocysts continuously through the end of the experiment, day 230 and 135 p.i., respectively. There were no parasitic stages or lesions in mice, as revealed by histological examination. Experiments proved that rodents serve as paratenic hosts for C. duszynskii. In summary we discuss the life-cycle strategies of Caryospora spp. in reptiles and present three general modes of their development.
Six new species of coccidia are described from endangered Phelsuma spp. geckoes (Sauria: Gekkonidae) endemic to Mauritius, Indian Ocean. Five new species (3 Eimeria and 2 Isospora species) are described from Phelsuma rosagularis Vinson et Vinson; all lack a micropyle and an oocyst residuum, and all have a sporocyst residuum. Oocysts of Eimeria swinnertonae sp. n. are ellipsoidal, 22.2 × 17.8 (20.8-24.8 × 16.8-18.4) μm; SI 1.25; polar granule absent. Sporocysts are ellipsoidal, 8.8 × 7.0 (8.0-9.6 × 6.4-8.0) μm; SI 1.3; Stieda body absent. Oocysts of Eimeria stebbinsi sp. n. are ellipsoidal, 17.4 × 11.7 (16.0-19.2 × 11.2-12.8) μm; SI 1.5; polar granules present. Sporocysts are elongate-ellipsoidal, 7.7 × 4.0 (7.2-8.0 × 3.2-5.6) μm; SI 1.9; Stieda body present. Oocysts of Eimeria raleighi sp. n. are spheroidal to sub-spheroidal, 17.0 × 15.5 (16.0-19.2 × 14.4-16.8) μm; SI 1.1; polar granule present. Sporocysts are sub-spheroidal, 7.8 × 6.6 (7.2-8.0 × 6.4-7.2) μm; SI 1.2; Stieda body absent. Oocysts of Isospora cottinghamae sp. n. are ellipsoidal, 19.8 × 15.5 (17.6-21.6 × 14.4-17.6) μm; SI 1.3; polar granules present. Sporocysts are ellipsoidal, 10.8 × 6.9 (9.6-12.8 × 6.4-8.0) μm; SI 1.6; Stieda body present. Oocysts of Isospora pearlae sp. n. are ellipsoidal, 16.0 × 11.5 (15.2-17.6 × 9.6-12.8) μm; SI 1.4; polar granule present. Sporocysts are ellipsoidal, 8.8 × 5.4 (8.0-9.6 × 4.8-6.4) μm; SI 1.6; Stieda and substieda bodies present. One new Eimeria species is described from the blue-tailed day gecko, Phelsuma cepediana Merrem. Oocysts of Eimeria hartleyi sp. n. are sub-spheroidal to ellipsoidal, 18.2 × 14.5 (16.0-20.8 × 13.6-16.0) μm; SI 1.26; polar granules present. Sporocysts are ellipsoidal to cylindroidal, 7.5 × 5.3 (6.4-8.0 × 4.8-6.4) μm; SI 1.4; Stieda body present. We report the presence of tetrazoic spheroidal to sub-spheroidal oocysts or sporocysts 10.2 × 8.5 (9.9-10.4 × 8.3-8.8) μm; SI 1.2 from an individual of P. cepediana. These oocysts or sporocysts are significantly larger than the Cryptosporidium species so far described from reptiles, and likely represent excretion of spuriously ingested sporocysts of a Sarcocystis or Adelina coccidian.