The comparison of the types of Phalotris tricolor (Duméril, Bibron & Duméril, 1854) and Elapomorphus punctatus Lema, 1979 showed that both names refer to a single species; up to date the current name P. tricolor is a compound of P. tricolor and an unknown species that is described here as P. matogrossensis sp. nov. from southwestern Brazil to adjacent Paraguay at Cerrado domain. The new species differs from P. tricolor mainly by white lower side of head, instead entirely black; white collar longer than the black collar, instead short with very longer black collar; black collar only dorsal, instead attaining ventral side; back ground coloration uniformly brilliant red, instead yellowish to brownish red, with widespread black dots usually in longitudinal series. The skull and hemipenis from both species do not present major differences. These species, plus P. mertensi (Hoge, 1955) and P. cuyanus (Cei, 1984), compose the tricolor group; a key is provided to identification of species.
New species; Phalotris tricolor; P. punctatus; distribution; taxonomy
