A new species of Eimeria Schneider, 1885 is described from an eastern gray squirrel (Sciurus carolinensis) from McCurtain County, Oklahoma, USA. Oöcysts of Eimeria lukfataensis n. sp. are ellipsoidal with a rough pitted bi-layered wall, measure 23.8 × 14.9 μm, and have a length/width (L/W) ratio of 1.6; a micropyle is absent but an oöcyst residuum and polar granule(s) are present. Sporocysts are ellipsoidal and measure 12.5 × 6.1 μm, L/W 2.0; Stieda and sub-Stieda bodies are present, but para-Stieda body is absent. The sporocyst residuum is composed of small indistinct granules along the edge or in the center of the sporocyst. This is the first species of coccidian reported from S. carolinensis from Oklahoma and only the fourth species from the sciurid tribe Sciurini with oöcysts possessing an oöcyst residuum.Publisher's Disclaimer: This article was registered in the Official Register of Zoological Nomenclature (ZooBank) as urn:lsid:zoobank.org:act:F3895ADD-F9C5-4846-9BAC-E3C9BC0E2E21. This article was published as an Online First article on the online publication date shown on this page. The article should be cited by using the doi number. This is the Version of Record.
Conflict of interestThe authors declare that they have no conflict of interest.Ethical approval All applicable institutional, national and international guidelines for the care and use of animals were followed. Scientific Collecting Permits were provided to CTM by the Oklahoma Department of Wildlife Conservation (permit number 7297).