The larva of Scinax similis (Cochran, 1952) is described from Ilha do Fundão (Rio de Janeiro, Rio de Janeiro State, Brazil). Comparisons with other species of the group that occur in Southeastern Brazil are added. The larva of S. similis can be distinguished by the following diagnostic features: (1) eyes large in relation to body length (17,3%), body height (26,8%), and body width (29,7%), interocular distance three times larger than eye diameter; (2) lower beak with two transverse stripes, proximal half white and distal half black.
Hylidae; Scinax similis; Scinax ruber group; larval morphology; Southeastern Brazil