sp. shed by the common boa snake () in Brazil.

The genus contains around 200 species and 25 of these infect snakes. Two spp. shed by snakes have called special attention of the scientific community. , which is shed by scrub pythons (), causes myopathy in humans that consume water or food contaminated with the parasite. Sporocysts of , excreted by reticulated pythons (), is letal for rats and was successfully tested in the biological control of these rodents. A high biodiversity of snakes is found in Brazil, however, scarce information is available about spp. in Brazilian snakes. Herein, we investigated sp. in feces of the common boa () from Salvador, as it is widely distributed in Brazil and it is also bred in other countries. Feces of 65 boas were examined, and sp. was found in 1/65 (1.53%) snakes. All snakes were alive, and for this reason, intestinal scrapping, which is the most sensitive method to detect the parasite, was not performed. Morphometric evaluation of sporocysts showed significant differences in their sizes. PCR and multilocus sequencing of four genetic markers (, ITS1, and ) revealed that sporocysts corresponded to a new species. Sequences of and had identities of 100% and higher than 98%, respectively, with sequences obtained from the rodent in Argentina. ITS1 and sequences did not match with any known sp. No ITS1 and sequences were available for the sp. found in the Argentinian Bioassay using the boa sporocysts was conducted in three mouse lineages and in , but no parasitic stages were detected in these rodents. We concluded that the common boa is probably the definitive host of a new species of sp. that has or related rodents as intermediate hosts.