Phylogenetic assessment of Plasmodium (Saurocytozoon) tupinambi comb. nov. (Haemosporida, Plasmodiidae) in golden tegu lizards: shedding light on a long-standing Haemosporida taxonomic puzzle.

Haemosporidians constitute a monophyletic group of vector-borne parasites that infect a wide range of vertebrate hosts, including Neotropical lizards. The remarkable diversity of these host-parasite associations and inadequate research on certain parasite groups have resulted in controversial haemosporidian taxonomy. Herein, we rediscover erythrocytic and non-erythrocytic haemosporidians infecting golden tegus (Tupinambis teguixin) from Brazil and Colombia. The erythrocyte-inhabiting parasite belongs to Plasmodium sp., and the non-erythrocytic form was identified as Saurocytozoon tupinambi, previously attributed to the Family Leucocytozoidae. These non-pigmented haemosporidian parasites do not multiply in the blood. The relationships between the Saurocytozoon and Leucocytozoidae species were discussed for many years, especially during the 1970s. However, cytochrome b (cytb) sequences and the mitochondrial genomes recovered for this species strongly support classifying this parasite as a Plasmodium taxon. Therefore, we proposed a new combination for this parasite, Plasmodium (Saurocytozoon) tupinambi comb. nov., where Saurocytozoon is retained as a subgenus due to its distinct morphology. These results reinforce that a broader definition of Plasmodiidae must include saurian parasites that develop non-pigmented leucocytozoid-like gametocytes.