Bioacoustics of Pithecopus rusticus (Anura, Phyllomedusidae): A Rare Species Possibly Threatened with Extinction

Vocalization is an important means of intra- and interspecific communication in anurans and is essential for reproduction. Here, we describe the advertisement and territorial calls of Pithecopus rusticus and determine the influence of air temperature and morphometric variables on advertisement call parameters. We recorded the vocalizations at the type-locality, in the municipality of Água Doce, state of Santa Catarina, southern Brazil, from September 2015 to February 2016. The advertisement call was composed of a short note, emitted sporadically, with a duration of 0.023 ± 0.002 ms (0.019–0.033 ms; n = 244). We recorded two types of territorial calls that were observed during the interaction between males. Territorial call I was composed of two notes and had a duration of 0.095 ± 0.043 ms (0.033–0.166 ms; n = 27). Territorial call II was a multipulsed note lasting 0.911 ± 0.340 ms (0.504–1.346 ms; n = 9) composed of 7–58 pulses emitted after territorial call I. Advertisement call duration was negatively related to air temperature. The duration and number of notes of the advertisement call of P. rusticus were similar to those of phylogenetically close species. Information on vocal repertoires of amphibians and factors influencing acoustic parameters are essential to understand the systematic taxonomy and evolution of groups, especially little-known species such as P. rusticus.