A new species of (Cestoda: Taeniidae) parasitizing (Carnivora: Mustelidae) from Patagonia, Argentina: Morphological and molecular characterization.

Via morphological and molecular analysis, we describe a new species of taeniid from Patagonia (Argentina): n. sp., parasitizing the Lesser grison (Molina) (Carnivora: Mustelidae). This is the first report of a species of in Argentina and for a native mustelid. The new species (the third in the genus ) is proposed using an integrative taxonomic approach, based on traditional morphology (distinctive morphological and morphometric diagnostic characters), genetic distances and phylogeny based on molecular data, the distinct geographical distribution, and the different definitive host species. n. sp. mainly differs from (Gmelin, 1790) (from Europe) in the number of testes (54-85 . 83-127 in ), the rostellum size (39-75 . 85-180 μm in ), the genital atrium size (170-420 . 68-91 μm in ) and in the hooks' shape. It also differs from the African species (Baer and Fain, 1951) by having smaller measurements regarding the main diagnostic characters, i.e. size of scolex, rostellum and suckers, number, size and shape of rostellar hooks, number of testes, and by having smooth cirrus (. cirrus covered with hair-like bristles in ). Phylogenetical analysis using cox1 showed our specimens clustering with North American isolates of sp. in a well-supported American clade (mean genetic divergence 0.024), separated from another clade composed of different isolates of (0.093). The close relationship between the new species and the North American species, known as "zoonotic" sp., and responsible for fatal infections by metacestodes in free-ranging wildlife (rodents), captive primates and immunosuppressed people, lead us to think that the zoonotic potential of n. sp. should not be discarded.