Description of Eimeria bubonis sp.n. (Protozoa: Eimeriidae) and Caryospora bubonis sp.n. (Protozoa: Eimeriidae) in the great horned owl, Bubo virginianus (Gmelin), of Saskatchewan

Abstract

Two new species of Eimeriidae are described from the great horned owl, Bubo virginianus (Gmelin), of Saskatchewan. The subspherical oocysts of Eimeria bubonis sp.n. are 22.8 ± 2.7 μm (18–30) long and 21.7 ± 2.4 μm (16–29) wide. The spindle-shaped sporocysts are 12.7 ± 1.1 μm (9.5–15.0) long and 7.8 ± 0.7 μm (5.8–10.0) wide. The polar granule, Steida body, and sporocyst residuum are present; the micropyle and oocyst residuum are absent. The oocyst wall is 0.8 μm thick, with a thick, clear outer layer and a thin, dark inner layer. Sporozoites, with a prominent conoid at the anterior end, are 13.1 ± 1.5 μm (10.0–16.3) long and 2.6 ± 0.3 μm (2.0–4.8) wide.The subspherical oocysts of Caryospora bubonis sp.n. are 43.9 ± 3.4 μm (38–52) long and 40.2 ± 2.8 μm (33–47) wide. The subspherical sporocysts are 26.6 ± 3.4 μm (20–33) long and 25.6 ± 2.4 μm (20–32) wide. The sporocyst residuum is present; the polar granule, Steida body, and oocyst residuum are absent. The oocyst wall is 1.1 μm thick, with a thick, clear outer layer and a thin, dark inner layer. The sporocyst wall is 0.8 μm thick with a thick, clear outer layer and a thin, dark inner layer. Sporozoites, with a prominent conoid at the anterior end, are 15.5 ± 1.9 μm (13.0–20.8) long and 2.5 ± 0.2 μm (2.3–3.0) wide.In both species, sporulation is complete in 96 h at 21 ± 2 °C.