Morphological, molecular and phylogenetic characterisation of Eimeria macyi Wheat, 1975 (Apicomplexa: Eimeriidae) in the eastern red bat Lasiurus borealis (Müller) from Mississippi, USA.

Abstract

In November 2017, oöcysts of the coccidian Eimeria macyi Wheat, 1975 were isolated from the faeces of a single eastern red bat Lasiurus borealis Müller in Lowndes County, Mississippi, USA. Sporulated oöcysts, morphologically consistent with previous accounts of E. macyi in other chiropterans, were spherical to sub-spherical in shape with a highly mamillated outer wall that appears bi-layered. Oöcysts allowed to sporulate in 2.5% potassium dichromate at ambient temperature (c.23°C) for 7 days were 17-25 × 15-20 (20.7 × 17.9) µm. Micropyle and oöcyst residuum were absent with one to two polar granules scattered among sporocysts. The four ovoid sporocysts were 7-12 × 6-8 (9.9 × 7.1) µm. Stieda bodies were prominent and sub-Stieda bodies were present. Two sporozoites were reflexed within each sporocyst. Nuclear 18S rRNA gene, plastid 23S rRNA gene and mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were sequenced from sporulated oöcysts and compared to other molecular data of Eimeria spp. from rodent and chiropteran hosts. No sequence data in the NCBI database matched E. macyi. Phylogenetic analyses of the sequence data of the 18S rRNA and 23S rRNA genes placed E. macyi within a clade containing Eimeria spp. from rodents and basal to a clade populated by sequences derived from Eimeria spp. of rodents and bats. This account represents a new host record of E. macyi in an eastern red bat and a new geographic locality. Additionally, the cox1 sequence data of Eimeria macyi represents the first mitochondrial sequence of an Eimeria sp. in bats.