The distribution of Phalotris tricolor group in Argentina and Paraguay, with notes on its taxonomy (Serpentes, Elapomorphini)

The species of tricolor group are redefined, because currently their limits are not very clear. Phalotris punctatus differs from P. tricolor mainly by dorsal coloration ocher reddish (vs. red), black dots widespread on dorsal side (vs. immaculate), smaller size, up to 770 mm, usually 400 mm (vs. up to 940 mm, usually 500), occurring in the biomes Monte Desert and Chaco, Argentina (vs. Austral Chaco, in Paraguay and Bolivia). Phalotris punctatus is similar to P. cuyanus differing of it mainly by presence of widespread dorsal dots (vs. absent; if present, few dots on vertebral row of scales); black head ventrally (vs. immaculate white), black snout (vs. immaculate ocher); reddish vertebral zone ocher (vs. fully ocher); and distribution in northern to western Argentina, barely reaching Paraguay (vs. northern Argentina, reaching Buenos Aires and neighboring Provinces). Keywords: Chaco, Monte, patterns, cuyanus, punctatus.