Isospora sepetibensis Berto, Flausino, Luz, Ferreira, Lopes 2008

Isospora sepetibensis Berto, Flausino, Luz, Ferreira, Lopes, 2008 (Fig. 1)

Description of sporulated oocyst: Oocyst shape (n = 18) sub-spherical to elongate ovoidal; 22–29 × 19–22 (25.9 × 20.7) length/width (L/W) ratio 1.1–1.4 (1.26). Wall bi-layered, 1.1–2.0 (1.3) thick, outer layer smooth, c. 2/3 of total thickness. Micropyle and oocyst residuum absent, but one or two polar granules are present.

Description of sporocyst and sporozoites: Sporocysts (n = 18), ellipsoidal, 15–18 × 9–11 (16.8 × 10.3); L/W ratio 1.5–1.8 (1.65). Stieda body present, knob-like, 1.1–1.3 (1.2) high, 2.0–2.2 (2.1) wide; sub-Stieda body present, large to trapezoidal or, occasionally, irregular, 1.2–2.3 (1.7) high, 2.7–3.5 (3.1) wide; para-Stieda body absent. Sporocyst residuum present, consisting of numerous small granules dispersed between the sporozoites or as a distinctly sub-spherical body that appear to be membrane-bounded, 5.5–6.7 (6.1). Sporozoite vermiform with one posterior refractile body, centrally located nucleus and striations.

Host: Trichothraupis melanops (Vieillot, 1818) (Passeriformes: Thraupidae: Tachyphoninae).

Locality: Itatiaia National Park (22°26’17.00”S, 44°37’33.00”W), Southeastern Brazil.

Specimens: Photomicrographs and oocysts in 2.5% K 2 Cr 2 O 7 solution (Williams et al. 2010) are deposited at the Museu de Zoologia at the Universidade Federal Ru- ral do Rio de Janeiro, Brazil, under accession number MZURPTZ2019014. Photomicrographs are also de- posited and available (http://r1.ufrrj.br/labicoc/colecao. html) in the Parasitology Collection of the Laboratório de Biologia de Coccídios, at UFRRJ, under repository number 92/2019. Photographs of the host specimens are deposited in the same collection.

Site in host: Unknown.

Prevalence: 67% (15 out of 10 birds infected).

Representative DNA sequence: Representative cox1 sequence is deposited in the GenBank database under the accession number MK682606.

Phylogenetic analysis: The amplification of the DNA from the fifteen oocysts of I. sepetibensis recovered from T. melanops showed a clear band of c. 250 bp. The phylogenetic analysis was constructed with 33 sequences of Isospora spp. closest to I. sepetibensis available on GenBank (Fig. 2). Eimeria tenella (Railliet, Lucet, 1891) was used as the outgroup. Isospora sepetibensis sat in a large group with the highest similarity of 98.1% with an Isospora sp. reported as pseudoparasite of bank voles Myodes glareolus (Schreber, 1780) in Czech Republic (Trefancová et al. 2019). It was close to the clade with Isospora isolates from the spectacled warbler Sylvia conspicillata Temminck, 1820 in Macaronesia (Illera et al. 2015); and also was close to the clade with Isospora spp. recently sequenced from Neotropical passerines (Silva-Carvalho et al. 2018a, 2018b; Rodrigues et al. 2019). Subsequently, a subset with only 215 bp long cox1 gene sequences was constructed (Fig. 3). In this analysis, Isospora sepetibensis sat in the same clade of Isospora spp. from Neotropical passerines, with the highest similarity of 98.5% with Isospora lopesi Silva-Carvalho & Berto, 2018 (Silva-Carvalho et al. 2018a).