Eimeria atricillae n. sp. (Apicomplexa: Eimeriidae) from the laughing gull Leucophaeus atricilla (Linnaeus) (Aves: Charadriiformes: Laridae) in Port Isabel, Texas

A new coccidian species, Eimeria atricillae n. sp. (Apicomplexa: Eimeriidae) collected from the laughing gull Leucophaeus atricilla , is reported from Port Isabel, Texas, USA. Sporulated oöcysts of the new species are spherical to subspherical, 16.0−18.1 × 14.4−16.6 (17.1 × 15.4) μm, with a length/width (L/W) ratio of 1.0−1.1; polar granules are present, but micropyle and oöcyst residuum are absent. Sporocysts are ovoid, 9.1−9.7 × 6.1−7.1 (9.4 × 6.6) μm, with a L/W ratio of 1.3−1.5; Stieda body present, but sub-Stieda and para-Stieda bodies are absent; sporocyst residuum diffuse.