A novel coccidian (Apicomplexa: Eimeriidae) from Scotophilus leucogaster (Chiroptera: Vespertilionidae) in southern Saudi Arabia.

Abstract

A novel species of coccidia, resembling a member of the genus Eimeria, was found in bats, Scotophilus leucogaster, collected in southern Saudi Arabia has been described on the basis of unsporulated oocysts and DNA sequencing of the Internal Transcribed Spacer 1 (ITS1) and partial 18S rDNA regions. Unsporulated oocysts of this form are ovoidal to spheroidal and had a 2-layered wall, 1.5-2.0 (1.9 ± 0.2); the outer layer was light blue with striations, and thicker than the inner, darker layer. No micropyle was present. Unsporulated oocysts (N = 150) measured 27.2 × 22.1 (25-30 × 20-25), length width ratio, 1.2 (1.1-1.4). There was no evidence of an oocyst residuum and/or polar granule. This parasite was detected in 2/7 (29%) S. leucogaster collected from southern Saudi Arabia. Oocysts incubated at 25°C in 2.5% K2Cr2O7 did not sporulate after > 1month. Unsporulated oocyst measurements were compared with other coccidian parasites of bats that discharge oocysts in their feces. Sequences of the ITS1 and the 18S rDNA regions obtained from the unsporulated oocysts grouped this coccidium from S. leucogaster with eimerian species from various rodent and squirrel species. It is critical that future investigators obtain fully sporulated oocysts of this coccidium for full description of the parasite recovered in our study so it can be correctly assigned to genus and given an accurate binomial.