Redescriptions are given of the mature oocysts of Eimeria aguti Carini 1935, E. cotiae Carini, 1935 and E. paraensis Carini, 1935 Following the examination of faeces from a single specimen of an agouti, which he referred to as "Cotia vermelha (Aguti aguti)", Carini (1935) described the mature oocysts of what he considered to be three distinct species of Eimeria, and named them E. paraensis, E. cotiae, and E. aguti. Pellérdy (1974) pointed out that the genus "Cotia" does not exist within the Class Mammalia and listed the host of these parasites as Dasyprocta aguti. This was corrected by Levine and Ivens (1990) to Dasyprocta leporina (Linnaeus, 1758), for which D. aguti is now considered to be a synonym (Hussan 1978). The animal was housed in the Parque Zoobotânico of the Museu Emilio Goeldi, in Belém, Pará, North Brazil, and although the exact locality of its origin was not given, it was most likely to have been somewhere in Pará.We have examined the faeces of 10 D. leporina, identified to species by cytogenic analysis, from two different areas of Pará: five of them were passing oocysts of Eimeria species which superficially resembled those described in D. leporina by Carini. In this communication we give re-descriptions of the mature oocysts of E. aguti and those previously described as E. paraensis and E. cotiae (Carini 1935): some endogenous stages, regarded as those of E. cotiae, are described in the ileum. Doubts are raised regarding separation of this parasite and E. paraensis.
MATERIALS AND METHODSThe agoutis were captured in fruit and vegetable-baited traps. Eight of the animals were from the municipality of Anajás, Island of Marajó, Pará (0.59 S : 49.57 W) and two from the Island of Caratateua (more popularly known as Outero), municipality of Belém, Pará (1.18 S : 48.28 W): they were maintained, in separate cages, on a diet of mixed fruit and vegetables and given water ad libitum. Faecal samples were obtained daily, lightly triturated in 2% aqueous potassium dichromate solution (K 2 Cr 2 O 7 ), kept at approximately 24ºC as thin layers in loosely covered Petri dishes, and examined for the presence of coccidial oocysts by both direct microscopical examination and the zinc sulphate flotation method (Baker 1969). Positive samples were examined daily to determine the time required for oocyst sporulation.In an attempt to locate the site of development of the parasites in D. leporina, two of the naturally infected animals were sacrificed, and a search made for endogenous stages in both the gall-bladder and intestinal epithelium. The entire alimentary tract was fixed in 10% buffered formalin for subsequent preparation of histological sections of the duodenum, ileum, caecum, and colon. Oocysts and sporocysts were measured using a x 100 neofluar objective and x 10 eyepieces with an ocular micrometer. Photomicrographs were prepared with a Zeiss "Photomicroscope III" and Kodak TMX 100 film. All measurements are given in µm and presented as means, with the range in parentheses, followed by the shape-index (ratio o...