We describe through integrative taxonomy a new species of snouted treefrog of the genus Scinax from white-sand forests of the Rio Negro Sustainable Development Reserve in Central Amazonia, Brazil. The new species is phylogenetically related to other Scinax with striped eyes and pulsed advertisement calls. It differs from other Amazonian species mainly by having snout–vent length 21.6–25.4 mm (n= 11) in adult males and 24.8–27.0 mm (n= 9) in females, snout subacuminate in dorsal view, a dark brown lateral stripe on each flank (fading posteriorly), brown tadpoles with labial keratodont row formula 2(2)/3 and keratodont row P-2 longer than P-1 and P-3, and an advertisement call consisting of a single pulsed note with a call duration of 502–652 ms, 79–105 pulses/note and a dominant frequency of 3,811–4,543 Hz. The new species clusters within a major, well-supported phylogenetic clade grouping several candidate and recently described species as well as species previously included in the former Scinax staufferi species group (viz., S. cruentomma, S. fuscomarginatus, S. staufferi, and S. wandae). The phylogenetic relationships and structural pattern in the advertisement calls of these species highlight the need for a redefinition and reevaluation of the monophyly of the S. staufferi species group.