Isospora machadoae sp. nov. (Protozoa: Apicomplexa: Eimeriidae), a new coccidian species from white-necked thrushes Turdus albicolis (Passeriformes: Turdidae) of South America Author de Pinho, Irlane F. Programa de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author da Silva, Lidiane M. Programa de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author Rodrigues, Mariana B. Programa de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author Lopes, Bruno do B. Programa de Pós-graduação em Ciência, Tecnologia e Inovação em Agropecuária, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author Oliveira, Mariana S. Programa de Pós-Graduação em Biologia Animal, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author Luz, Hermes R. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author Ferreira, Ildemar Departamento de Biologia Animal, Instituto de Ciências Biológicas e da Saúde, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. .ufrrj@gmail.com Author Lopes, Carlos Wilson G. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. Author Berto, Bruno P. Departamento de Biologia Animal, Instituto de Ciências Biológicas e da Saúde, Universidade Federal Rural do Rio de Janeiro. Campus Seropédica, Rio de Janeiro, Brazil. text Zoologia 2018 e 24570 2018-03-09 35 1 4 http://dx.doi.org/10.3897/zoologia.35.e24570 journal article 300556 10.3897/zoologia.35.e24570 f4582238-74e7-4f07-8562-8a2ced8edf08 1984-4689 13175416 1958A69A-870C-43A7-8845-AFF87B9F40D2 Isospora machadoae sp. nov. http://zoobank.org/ 1F9B7A3F-100D-45CE-8162-7E534A9DAAE5 Figs 1, 2 Diagnosis. Among all coccidian species recorded from Turdidae in the New World, only I. machadoae sp. nov. has an oocyst wall rough with micropyle and micropyle cap, which are very uncommon characteristic features in Isospora spp. from Passeriformes ( Table 1 ). In addition, I. machadoae sp. nov. differed from others in having ellipsoidal sporocysts with Stieda body flattened to half-moon-shaped. Description. Oocyst (n = 35) spherical to sub-spherical, 21–24 × 20–23 (22.2 × 21.2); length/width (L/W) ratio 1.0–1.2 (1.1). Wall bi-layered, 1.2–1.5 (1.3) thick, outer layer rough, with 2/3 of total thickness. Micropyle present with 7.0 wide. Micropyle cap present with slight protrusion, but barely discernible in some oocysts ( Figs 1, 2 ). Oocyst residuum absent, but one or two sub-spherical, robust and refringent polar granules are present. Sporocysts (n = 26) 2, ellipsoidal, 12-14 × 9–11 (13.3 × 9.7); L/W ratio 1.2–1.5 (1.4). Stieda body present, flattened to half-moon-shaped, 0.5 high × 1.5 wide; sub-Stieda present, rounded, 1.5 high × 2.5 wide; para-Stieda body absent; sporocyst residuum present, composed of scattered spherules of different sizes. Sporozoites 4, vermiform, with a posterior refractile body and a nucleus. Type host. White-necked thrush Turdus albicollis Vieillot, 1818 ( Aves : Passeriformes : Turdidae ). Type material. Phototypes , line drawing, half of the oocysts in 10 % aqueous buffered formalin (v/v) and the other half in 70 % ethanol are deposited at the Museu de Zoologia da Universidade Federal Rural do Rio de Janeiro , Brazil , under accession number MZURPTZ2017001. Phototypes and line drawings are also deposited 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 P-70/2016. Photographs of the type-host specimen (symbiotype) are deposited in the same collection . Type locality. Parque Nacional do Itatiaia ( 22°27’38”S , 44°35’34”W ), Southeastern Brazil . Other locality. Visconde de Mauá ( 22 °19 ’46”S , 44°32’11”W ), Southeastern Brazil . Etymology. The specific name is derived from the family name of a Brazilian parasitologist Dr Rosangela Zacarias Machado, given in her honor for her contribution to the study of Protozoa. Figures 1–2. Sporulated oocysts of Isospora machadoae sp. nov. recovered from Turdus albicolis from Brazil: (1) line drawing; (2) photomicrographs. Note the micropyle and micropyle cap (m/mc), nucleus (n), polar granule (pg), refractile body (rb), rough oocyst wall (row), Stieda (sb) and sub-Stieda bodies (ssb) and the sporocyst residuum (sr). Scale bar = 10 µm. Table 1. Comparative morphology of Isospora spp. recorded from Turdidae of the New World.

Oocysts		Sporocysts
Coccidia	Hosts	References	Shape	Length (µm)	Width (µm)	L/W ratio	Wall	Micropyle	Micropyle cap	Polar granule	Shape	Length (µm)	Width (µm)	L/W ratio	Stieda body	Substieda body	Residuum
Isospora phaeornis	Myadestes obscurus	Levine et al. (1980)	Ellipsoidal	25–28 (27)	18–20 (19)	–	Smooth	absent	Absent	Present	Ovoidal	15–18 (16)	10–11 (11)	–	Present	Present	Compact
Isospora robini	Turdus migratorius	McQuistion and Holmes (1988)	Ellipsoidal or ovoid	20–28 (23)	16–22 (20)	(1.2)	Smooth	absent	Absent	Present	Ovoid	10–17 (13.8)	7–12 (9.0)	(1.5)	Nipple- like	Present, prominent	Compact
Isospora tucuruiensis	Turdus albicollis	Lainson and Shaw (1989)	Sub- spherical	15–19 (17.3)	14–19 (17.1)	–	Smooth	absent	Absent	Present, single,~ 3 × 2	Ellipsoidal	10–13 (11.8)	7–10 (8.4)	–	Nipple- like	Present, wide, ~ 0.5 × 1.5	Diffuse or compact
Isospora albicollis	T.albicollis	Lainson and Shaw (1989)	Ovoidal	22–27 (24.5)	19–24 (20.3)	–	Smooth	present	Absent	Present, single,~ 2.5 × 2	Ellipsoidal	12–15 (16.0)	8–10 (11.2)	–	Nipple- like to bubble- shaped	Present, wide, ~ 1.0 × 4	Diffuse or compact
Isospora zorzali	Catharus aurantiirostris	Keeler et al. (2012)	Round to slightly ovoid	16–24 (19.7)	15–21 (18.6)	(1.1)	Smooth	absent	Absent	Present, 1 to 2	Ovoidal	11–18 (14.5)	7–11 (8.5)	(1.7)	Nipple- like	Absent	Diffuse or compact
Isospora massardi	T.albicollis	Lopes et al. (2014)	Sub- spherical	15–21 (18.6)	14–19 (17.7)	1.0–1.1 Smooth (1.1)		absent	Absent	Present,2 ellipsoidal Granules, 1.5 × 0.5	Ovoidal	13–16 (14.8)	8–11 (9.3)	1.4–1.8 (1.6)	Knob- like to rounded, 1 × 2	Present, rounded, 1.5 × 3.5	Diffuse
Isospora machadoae	T.albicollis	Current work	Sub- spherical	21–24 (22.2)	20–23 (21.2)	1.0–1.2 (1.1)	Rough	present	Present	Present,1 to 2, sub- spherical and robust	Ellipsoidal	12–14 (13.3)	9–11 (9.7)	1.2–1.5 (1.4)	Present, flattened to half- moon- shaped, 0.5 × 1.5	Present, rounded, 1.5 × 2.5	Diffuse

Remarks. According to Duszynski and Wilber (1997) and Berto et al. (2011) , a coccidian species should be compared in detail with coccidian species that are feature-similar and belong to the same host family. The Turdidae is one of the families of Passeriformes with many descriptions of coccidian parasites, mainly considered the flycatchers, robins and nightingales classified in the past as turdids. Currently, from the New World, only the six species cited in Table 1 are recorded from Turdidae ( Berto et al. 2011 , Cardozo et al. 2015 ). The white-necked thrushes captured in the current work had no apparent clinical signs of coccidiosis or high densities of oocysts in feces. This condition may be associated with a specific low pathogenicity of I. machadoae sp. nov. and/or with the good conservation status of the Parque Nacional do Itatiaia and Visconde de Mauá, which ensures the ecological niches and thus the immunocompetence to wildlife ( Dorrestein 2009 , Berto and Lopes 2013 ).