Coccidia of Wombats: Correction of Host-Parasite Relationships. Eimeria wombati (Gilruth and Bull, 1912) comb. nov. and Eimeria ursini Supperer, 1957 from the Hairy-Nosed Wombat and Eimeria arundeli sp. n. from the Common Wombat

Abstract

Coccidial oocysts morphologically consistent with Eimeria ursini Supperer 1957, and E. tasmaniae Supperer 1957 were recovered from the feces of wild and captive hairy-nosed wombats (Lasiorhinus latifrons) in Australia. Eimeria arundeli so. n. was recovered from the feces of wild and captive common wombats (Vombatus ursinus). Eimeria arundeli oocysts are ellipsoidal to slightly ovoid 60.2--67.2 (63.7) X 40.6--47.6 (43.4); micropyle 3 in diameter usually visible; with oocyst wall granular, dark brown and occasionally opaque, 4--7 thick; inner oocyst wall clear, about 1.5 thick; small oocyst residuum present, four sporocysts ovoid 22.4--29.4 (25.8) X 12.6--15.4 (14.1) with protuberant Stieda body; opposite end of sporocyst also often slighly pointed; large granular sporocyst residuum obscuring sporozoites. Gametocytes of E. arundeli sp. n. and of an organism which is consistent with E. tasmaniae, are described developing in the lamina propria of villi in the small intestine. The stages in the hairy-nosed wombat are those described as Ileocystis wombati Gilruth and Bull 1912. It is suggested that the identification of the host of Supperer's E. ursini and E. tasmaniae as V. ursinus was in error and that the allopatric L. latifrons is the natural host. Eimeria tasmaniae Supperer 1957 is suppressed and E. wombati (Gilruth and Bull, 1912) comb. nov. is proposed and redescribed. No schizonts were identified among the endogenous stages, consistent with observations in the literature on other coccidia with similar gametocyte and oocyst structure.

Wildlife parasitology in Australia: past, present and future

“…The coccidia (Eimeria spp.) of macropodids and wombats have been studied relatively intensely primarily because of their association with fatal, or at least debilitating, disease in their hosts (Barker et al 1972(Barker et al , 1979(Barker et al , 1988a(Barker et al , 1988b(Barker et al , 1988c(Barker et al , 1989O'Callaghan et al 1998). However, the coccidians of few other groups of marsupials have been described even though they are known to be present (e.g.…”