A New Species of Acroeimeria Paperna and Landsberg, 1989 (Apicomplexa: Eimeriidae) from the Broad-Headed Skink, Plestiodon laticeps (Sauria: Scincidae: Scincinae), in Southwestern Arkansas, USA, with Additional Information on Choleoeimeria fasciatus

Although an isosporan coccidian has been reported from the broad-headed skink, Plestiodon laticeps (Schneider), no acroeimerians are known from this reptile. A single fecal sample was collected by hand in June 2025 from a female P. laticeps from Nevada County, Arkansas, USA. The sample was placed in a vial containing 2.5% potassium dichromate. It was examined for sporulated oocysts after flotation in Sheather’s sugar solution, measured, and photographed. The skink was found to be passing a new species of Acroeimeria Paperna and Landsberg, 1989. Oocysts of Acroeimeria nevadaensis sp. n. were spheroidal with a smooth bi-layered wall, measured (L × W) 15.6 × 13.7 µm, and had a length/width (L/W) (shape index) average ratio of 1.1; micropyle and oocyst residuum were absent but one to two polar granule(s) were present. Sporocysts are ovoidal and measured 7.7 × 5.9 µm, L/W ratio of 1.3; Stieda, sub-Stieda, and para-Stieda bodies were absent. The sporocyst residuum was composed of a loose aggregate of various-sized granules between and across the sporozoites but sometimes a compact, rounded, or irregular mass. In addition, new data on oocysts matching the description of Choleoeimeria fasciatus from the same host are provided. Here, we document a description of a new species of Acroeimeria as well as provide a new host and geographic distribution record, photomicrographs, and mensural and morphological data for a choleoeimerian from this skink. This is the first acroeimerian reported to be from P. laticeps and, more importantly, the second known to be from members of the family Scincidae of the world.