Data analysis of The tadpoles and advertisement call of Trachycephalus imitatrix and T. dibernardoi (Anura: Hylidae)

Herein, we describe the external larval morphology, internal oral features, and chondrocranium of <i>Trachycephalus imitatrix </i>and<i> T. dibernardoi</i> and the advertisement call of <i>T. imitatrix</i>. To our knowledge, this is the first thorough description of the larval chondrocranium for the genus <i>Trachycephalus</i>.<i> </i>The tadpole of <i>T. imitatrix</i> is overall similar to the other congeneric species, but can be distinguished from them by the following combination of characteristics: presence of two folds in the posterior labium, clumped submarginal papillae, tail ending in a flagellum, buccal roof arena lacking papillae, and seven postnarial papillae. The tadpole of <i>T. dibernardoi</i> can be distinguished from its congeners by the following combination of characteristics: snout rounded in lateral view, absence of interruption in teeth rows, uniseriate and alternated row of marginal papillae, two pairs of infralabial papillae, absence of projection of the dorsal velum. The advertisement call of <i>T. imitatrix</i> is very similar to that of <i>T. nigromaculatus</i> but can be distinguished from it by its lower dominant frequency. Additionally, both spectral and temporal features of the call can distinguish <i>T. imitatrix</i> from other congeneric species. Our results help understand the differentiation of larval and acoustical characteristics within the genus <i>Trachycephalus</i>.