Hyloxalus marmoreoventris (Río Negro rocket frog)
Hyloxalus marmoreoventris (Rivero, 1991)
It is a small frog; males have white spots on the abdomen. It is distinguished from Hyloxalus fallax by its spotted venter. Both species are similar in lacking the oblique, dorsolateral and ventrolateral lines and in lacking toe webbing (1).