Spectrograms and oscillograms of calls of the cooperi and erlangeri species groups A P. cooperi B P. amharensis C P. erlangeri D P. levenorum E P. nana F P. robeensis sp. nov.

  Part of: Goutte S, Reyes-Velasco J, Freilich X, Kassie A, Boissinot S (2021) Taxonomic revision of grass frogs (Ptychadenidae, Ptychadena) endemic to the Ethiopian highlands. ZooKeys 1016: 77-141. https://doi.org/10.3897/zookeys.1016.59699