A New Species of Plasmodium of the Subgenus Novyella Infecting White-Shouldered Fire-Eyes (Pyriglena leucoptera) (Aves: Thamnophilidae) in Brazil.

Bird parasites belonging to the genus Plasmodium (Haemosporida: Plasmodiidae) are found worldwide, with over 50 described species categorized into five subgenera. The subgenus Novyella comprises 22 morphologically identified species, of which 59% are genetically associated with at least one haplotype. In the Americas, only three morphospecies have their microscopic characteristics linked to a molecular signature. In this study, we described a new species of Plasmodium (Novyella) infecting a white-shouldered fire-eye (Pyriglena leucoptera) in Brazil. Molecular analysis reveals that the new species, associated with the lineage PYLEU01, is closely genetically related to Plasmodium (Novyella) homopolare, exhibiting a genetic divergence of 4.18%. However, it differs from P. homopolare due to the presence of many mature amoeboid trophozoites and some young meronts located laterally in relation to the erythrocyte nuclei and the smaller average number of merozoites in mature erythrocytic meronts. Morphology of blood stages of new species is most similar to Plasmodium vaughani and Plasmodium rouxi, but is different from these parasites due to the presence of predominantly 4 merozoites in mature erythrocytic meronts (not characteristic of P. vaughani) and the presence of 5-6 merozoites in some mature erythrocytic meronts (not characteristic of P. rouxi). Our integrative analyses reveal that the newly described species represents a distinct Plasmodium parasite from other Novyella morphospecies.