Molecular diversity and coalescent species delimitation of avian haemosporidian parasites in an endemic bird species of South America

Haemoproteusspp. andPlasmodiumspp. are blood parasites that occur in birds worldwide. Identifying the species within this group is complex, especially in wild birds that present low parasitemia when captured, making morphological identification very difficult. Thus, the use of alternative tools to identify species may be useful in the elucidation of the distribution of parasites that circulate in bird populations. The objectives of this study were to determine the prevalence and parasitemia of the generaPlasmodiumandHaemoproteusinTachyphonus coronatusin the Atlantic Forest, Brazil, and to evaluate the molecular diversity, geographic distribution, and specificity of these parasites based on coalescent species delimitation methods. Microscopic analysis, PCR,cyt bgene sequencing, phylogenetic analysis and coalescent species delimitation using single-locus algorithms were performed (Poisson tree process (PTP) and multi-rate Poisson tree process (MPTP) methods). The analyses were performed in 117 avian host individuals. The prevalence was 55.5% forPlasmodiumand 1.7% forHaemoproteus, with a mean parasitemia of 0.06%. Twenty-fivePlasmodiumand twoHaemoproteuslineages were recovered. The MPTP method recovered seven different evolutionarily significant units (ESUs) ofPlasmodiumand one ofHaemoproteus, whereas PTP presented fourteen ESUs ofPlasmodiumand one ofHaemoproteus. The MPTP was more consistent with current taxonomy, while PTP overestimated the number of lineages. These ESUs are widely distributed and have already been found in 22 orders of birds that, all together, inhabit every continent, except Antarctica. The computational methods of species delimitation proved to be effective in cases where the classification of Haemosporida based just on morphology is insufficient.