Detecção, caracterização e taxonomia de hemosporídeos em Cariama cristata: destaque para a primeira descrição morfológica de uma espécie nova de Leucocytozoon no Brasil

Abstract

The distribution of haemosporidian parasites of the genus Leucocytozoon in neotropical lowland regions and in mid and low plateaus territories is poorly understood. Recent studies have confirmed their presence in the region using molecular techniques alone, but evidence for gametocytes and data on putative competent hosts for Leucocytozoon in the local fauna are still lacking. In this study, we combined morphological and molecular data to characterize a new Leucocytozoon species in the peripheral blood of a Red-legged Seriema (Cariama cristata), a South American non-migratory bird found in the Brazilian Cerrado and received by the Centro de Triagem de Animais Silvestres de Belo Horizonte (CETAS-BH). This new parasite species is distinguished from the Leucocytozoon fringillinarum group by its microgametocytes that do not touch or are not strongly appressed to the host's nucleus. The bird studied was co-infected with Haemoproteus pulcher, and we present a Bayesian phylogenetic analysis based on nearly complete mitochondrial genomes of these two parasites. Given its unique morphology and distant mtDNA phylogenetic relationships with other Haemosporida, Leucocytozoon cariamae n. sp. does not share a recent common ancestor with the L. fringillinarum group. Additionally, H. pulcher and Haemoproteus catharti, a Turkey Vulture parasite (Cathartes aura) and whose mitochondrial genome was also characterized in the present work, form a monophyletic group with the genus Haemocystidium. Our study represents the first report of a competent host for Leucocytozoon in the Neotropical plateaus and provides two possible taxonomic hypotheses that justify the placement of H. catharti and H. pulcher closer to Haemocystidium than to other Haemoproteus.