Programa de Pós-Graduação em Biologia Animal, Instituto de Ciências Biológicas e da Saúde, Universidade Federal Rural do Rio de Janeiro, BR-465 km 7, 23897-000 Seropédica, Rio de Janeiro, Brazil.
Departamento de Microbiologia e Imunologia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR-465 km 7, 23897-000 Seropédica, Rio de Janeiro, Brazil.
Parasitol Int. 2024 Dec;103:102936. doi: 10.1016/j.parint.2024.102936. Epub 2024 Jul 24.
Spinetails are a suboscine passerines of the genus Synallaxis Vieillot, 1818 which have great interest for ornithology, given the wide diversity of 37 species that are distributed throughout the Neotropical region. Despite this wide diversity and distribution, Synallaxis spp. have never been recorded as hosts of coccidian parasites. In this context, the current study describes a new species of Isospora Schneider, 1881 from rufous-capped spinetails Synallaxis ruficapilla Vieillot, 1819 captured in the Itatiaia National Park, which is a federal conservation unit in Southeastern Brazil. The oocysts of Isospora pichororei Genovez-Oliveira & Berto n. sp. are subspheroidal to ovoidal, measuring on average 25 by 21 μm. Micropyle is present, but discrete. Oocyst residuum absent, but one or two polar granules are present. Sporocysts are ellipsoidal with slightly pointed posterior end, measuring on average 17 by 10 μm. Stieda and sub-Stieda bodies are present. Sporocyst residuum is clustered among the vermiform sporozoites, which have striations, refractile bodies and nucleus. This morphology was different from the other Isospora spp. recorded in the host family Furnariidae. Molecular identification was targeted by the amplification and sequencing of a locus of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This sequence had the highest similarity of 99.5% with a sequence deposited for Isospora oliveirai Ortúzar-Ferreira & Berto, 2020, which is a coccidian species that parasitizes suboscine tityrids Schiffornis virescens (Lafresnaye, 1838), also in the Itatiaia National Park. Phylogenetic analysis grouped some species in subclades, including I. pichororei with I. oliveirai; however, it was inconclusive in an expectation of parasite-host coevolution. Finally, I. pichororei is established as new to science, being the first description from Synallaxinae and the third description from Furnariidae. Furthermore, this is the first Isospora sp. from the host family Furnariidae to have a molecular supplementation by sequencing a locus of the cox1 gene of the mitochondrial genome.
旋木雀是旋木雀属（Synallaxis Vieillot, 1818）的亚鸣禽雀形目鸟类，因其分布在新热带地区的 37 个物种的广泛多样性而引起鸟类学的极大兴趣。尽管具有这种广泛的多样性和分布范围，但 Synallaxis spp.从未被记录为球虫寄生虫的宿主。在这种情况下，目前的研究描述了一种来自红帽旋木雀（Synallaxis ruficapilla Vieillot, 1819）的新等孢球虫（Isospora Schneider, 1881）物种，该种鸟在巴西东南部的伊塔蒂亚伊国家公园被捕获。Isospora pichororei Genovez-Oliveira & Berto n. sp. 的卵囊呈亚球形到卵形，平均大小为 25 乘 21μm。微口存在，但不明显。无卵囊残体，但有一个或两个极粒。孢子囊呈椭圆形，后端略尖，平均大小为 17 乘 10μm。斯氏小体和次斯氏小体存在。孢子囊残体聚集在具有条纹、折射体和核的蠕虫状孢子中。这种形态与在宿主家庭灶鸟科中记录的其他等孢球虫不同。通过扩增和测序线粒体细胞色素 c 氧化酶亚单位 1（cox1）基因的一个基因座，进行了分子鉴定。该序列与 Isospora oliveirai Ortúzar-Ferreira & Berto, 2020 的序列相似度最高，为 99.5%，后者是一种寄生在伊塔蒂亚伊国家公园的亚鸣禽灶鸟（Schiffornis virescens）（Lafresnaye, 1838）中的球虫。系统发育分析将一些物种分组到亚分支中，包括 I. pichororei 和 I. oliveirai；然而，在寄生虫-宿主协同进化的预期中，这并不明确。最后，I. pichororei 被确认为新的科学发现，这是旋木雀亚科的首次描述，也是灶鸟科的第三次描述。此外，这是来自灶鸟科宿主的第一个具有通过测序线粒体基因组 cox1 基因座进行分子补充的等孢球虫。
