Hidden Apicomplexa diversity in cane toad Rhinella marina from the Brazilian Amazon, with description of a new Lankesterella species.

The present study aimed: (i) morphologically describe and molecularly characterize a novel Lankesterella species infecting anurans collected in the Pará state, Brazil; (ii) to record Dactylosoma infection in Rhinella marina, with phylogenetic information about the Dactylosoma species clade in Brazil; (iii) to record Hemolivia stellata infection in R. marina, providing the first genetic sequence of this parasite species from amphibians. The samples were collected between March 2023 and December 2024 in three localities of Pará state: Mosqueiro beach district, Natura Ecoparque and Treviso Farm. Thirty-six specimens of R. marina were captured through active search and blood samples were collected by cardiac puncture. A few drops of blood were used to prepare blood smears for microscopical analysis, and another aliquot was stored in ethanol for further molecular analyses. For molecular analyses, only microscopy positive samples were considered. Eight specimens were positive for hemoparasites: Dactylosoma sp. (n = 6), H. stellata (n = 3), and Lankesterella sp. (n = 2). The total number of infected hosts and the number of parasite records are not identical because co-infections occurred. Combining morphological analysis and molecular data, we described Lankesterella amazonica n. sp. We also provided the first molecular characterization of H. stellata in R. marina from the Brazilian Amazon. This study expands the known occurrence area and hosts of Lankesterella species in amazonian region bufonids, while also providing information about other blood parasites of Brazilian Amazon anurans.