A new species of Acroeimeria Paperna & Landsberg, 1989 (Apicomplexa: Eimeriidae) in Wiegmann's torquate lizard Sceloporus torquatus torquatus Weigmann (Sauria: Phrynosomatidae) from Toluca Valley, México.

A new species of Acroeimeria Paperna & Landsberg, 1989 is described from Wiegmann's torquate lizard Sceloporus torquatus torquatus Wiegmann from Toluca, México. Oöcysts of Acroeimeria wiegmanni n. sp. are sub-spheroidal with a smooth bi-layered wall, measure on average 28.6 × 23.6 µm, and have a length/width (L/W) ratio of 1.2; a micropyle and an oocyst residuum are absent but polar granule(s) are present. Sporocysts are ellipsoidal and measure on average 11.7 × 8.6 µm, L/W 1.3; Stieda, sub-Stieda and para-Stieda bodies are absent. The sporocyst residuum is composed of numerous spheroidal granules in the center of the sporocyst. Endogenous stages of the new species develop in the duodenum of hosts. This is the first species of coccidian reported from S. t. torquatus and one of the few reported from a reptile in México.