Hidden diversity and host specificity of bat trypanosomes in East and Central Africa

Bats are recognized as key reservoir hosts for a variety of trypanosomes, yet their full diversity and host associations remain underexplored in Africa. In this study, we investigated the diversity and phylogenetic relationships of trypanosomes infecting bats in Uganda and the Central African Republic (CAR) using molecular tools. A total of 22 distinct genotypes were identified, clustering into seven well-supported phylogroups, including known species such as Trypanosoma dionisii, T. livingstonei, T. vespertilionis, and T. erneyi, alongside several novel lineages. Notably, T. erneyi was restricted to Mops condylurus, reaffirming its narrow host specificity. Phylogenetic analyses revealed substantial intraspecific diversity in T. livingstonei and T. vespertilionis, suggesting potential cryptic species, while T. dionisii exhibited limited genetic divergence across a broad geographic range. Intriguingly, a unique and highly diverse phylogroup was detected exclusively in fruit bats (Pteropodidae) from Uganda, closely related to the Australian T. teixeirae, and likely represents a novel species. The absence of trypanosomes in fruit bats from CAR, despite similar sampling effort, hints at ecological or evolutionary factors shaping parasite distribution. Our findings expand the current knowledge of bat-trypanosome diversity and highlight the importance of African bat populations in understanding the evolutionary dynamics of trypanosomes.