The study of the labial teeth row distribution of 142 Ololygon fuscovaria larvae showed that it can be found two dental formulae a: 1,1-1/1-1.2 and b: 1,1-1/3. The P-1 row could have variations on b distribution, but they do not modify the formula that the tadpole gots during the premetamorphosis stages.
Echeverría, D. & Montanelli, S. (1992). Contribución al conocimiento de las larvas de Ololygon fuscovaria (Lutz, 1925) (Anura: hilydae). I. Distribución de los queratodontos. Cuadernos de Herpetología, 7 (1), pp. 1-4