Rediscovery of Plasmodium (Huffia) huffi (Apicomplexa, Haemosporida): a lost lineage from toucans.

Literature data on toucans haemosporidians are scarce and all reports come from investigations in Brazil. Muniz et al. (Rev Bras Malariol 3: 339-356, Muniz et al., Rev Bras Malariol 3:339-356, 1951) and Muniz and Soares (Rev Bras Malar 611-617, Muniz J, Soares R de RL (1954) Nota sôbre um parasita do gênero Plasmodium encontrado no Ramphastos toco Müller, 1776, "Tucano-Açu", e diferente do Plasmodium huffi: Plasmodium pinottii n. sp. Rev Bras Malar 611 - 617.) described two Plasmodium species, P. huffi and P. pinottii, in Ramphastos toco. Later, Manwell and Sessler (J Protozol 18: 570-574, Manwell and Sessler, Malaria Parasites of Toucans J Protozol 18:570-574, 1971) established a new subspecies, P. nucleophilum toucani. In the last review on avian haemosporidians, Valkiūnas (Valkiūnas, Avian malaria parasites and other haemosporidia, CRC Press, New York, 2005) highlighted that P. huffi was insufficiently characterized, considering it a lost lineage. Also, the original description of P. huffi was considered insufficiently clear, due to a possible co-infection of the toucan hosts with a Novyella-like species. Here, we redescribed the species Plasmodium (Huffia) huffi based on morphological and molecular data, which were found in two toucan species, Ramphastos toco and Pteroglossus aracari from Brazil. Morphological features of the specimens are markedly the same as the original description. In R. toco, we observe two individuals infected, one infected only with P. huffi and one co-infected with P. huffi and the Novyella-like species, as observed in the original description. Also, we observe one R. toco infected only with the Novyella-like species, identified by morphological and molecular data as Plasmodium (Novyella) nucleophilum nucleophilum. In this way, it was possible to redescribe Plasmodium huffi in detail, without the doubt characters observed in the original description. Moreover, by applying species delimitation algorithms to a large Plasmodium phylogeny, we were able to identify new possible hosts for P. huffi and extend its geographic distribution to include North America.