A new ‘horned' Stenocercus from the highlands of southeastern Brazil, and redescription of Stenocercus tricristatus (Reptilia: Tropiduridae)

A new species of the lizard genus Stenocercus Duméril & Bibron, 1837 is described based on six specimens from Serra da Canastra, Minas Gerais, southeastern Brazil. Similar to S.tricristatus (Duméril, 1851), S.dumerilii (Steindachner, 1867), S.quinarius Nogueira & Rodrigues, 2006, and S.squarrosus Nogueira & Rodrigues, 2006, the new species has a pyramidal head and an enlarged, dorsally projected post-supraciliary scale, like a small horn. It is most similar to S.tricristatus, from which it differs in having a more elongated head in ventral view; a larger number of scales around midbody; a distinctly enlarged, smooth preauricular scale; and probably a larger body size. Moreover, the new species has distinctly keeled scales, with phylloid and mucronate dorsals; no enlarged supraoculars; no neck folds; a vertebral, and a pair of dorsolateral and (weak) lateral crests. A redescription of S.tricristatus is presented for comparison with the new species.