This research investigates morphological differentiation between the amphibian species *Scinax alter* and *Scinax tymbamirim* in the Restinga de Jurubatiba National Park (PNRJ), located in the northern part of Rio de Janeiro state. Given the high visual similarity and the syntopic coexistence of these species within the *restinga* ecosystem, the study employs geometric morphometrics as a computational tool to isolate subtle anatomical nuances that traditional morphology fails to capture. This methodological approach builds upon previous results obtained for the species *Aparasphenodon brunoi*, in which the technique successfully discriminated variations in head shape among individuals.

The primary objective of this study is to apply geometric morphometrics to the head and hand regions of these anurans to identify consistent differences that allow for the statistical discrimination of the two species. To isolate taxonomic variation from sex-related traits, the sample is standardized and consists exclusively of adult males from scientific collections (with a minimum of 30 individuals per species).