There are 31 horned leaf frogs in genus Proceratophrys which is distributed in Brazil, northeastern Argentina, and Paraguay. The Black Horned Frog, Proceratophrys melanopogon was described based on one adult female from Alto da Serra, Municipality of Paranapiacaba, São Paulo, Brazil in 1926. The species was not accepted as valid by some, but the species was revalidated in 1990 and data on morphology, and natural history became available. Proceratophrys melanopogon is restricted high elevations of the Atlantic rainforest of southeastern Brazil on the south, central, and northern portions of the State of Rio de Janeiro.
Mângia and colleagues (2014) recently reviewed of Proceratophrys melanopogon taxonomy based on morphological, morphometric, and bioacoustic data from across the species distribution. The results revealed four populations have sufficient differences in call and morphology to be considered as new species allied to Proceratophrys melanopogon.
The authors found P. gladius sp. nova and P. melanopogon living in sympatry in the Serra da Bocaina. The cryptic Proceratophrys melanopogon and P. mantiqueira sp nova share morphological characteristics, but they have differences in external morphology and advertisement calls that promptly distinguish them as distinct species. The geographic distributions of P. melanopogon and P. mantiqueira reflect the mountain ranges of the Atlantic Forest from southeastern Brazil.
Mângia S, Santana DJ, Gonçalves Cruz, CA, Feio, RN. 2014. Taxonomic review of Proceratophrys melanopogon (Mirandaribeiro, 1926) with description of four new species (Amphibia, Anura, Odontophrynidae). Boletim Do Museu Nacional Zoology (531): 1-36.