AbstractThe genus Austrochaperina Fry, 1912, currently includes 23 species of small and medium-sized frogs which occur primarily in New Guinea and its surrounding islands. Through studies of the frog fauna carried out in various years between 1998 and 2003 in the Wondiwoi Mountains at the base of the Wandammen Peninsula, located on the border between the Indonesian provinces of Papua and Papua Barat, the author noted three forms in the genus Austrochaperina. One of these has already been described as a new species, A. minutissima, by Günther (2009). The second is most likely A. macrorhyncha (Kampen, 1906), which was described from a single available specimen from the Vogelkop Peninsula. Data provided herein by the author makes it clear that the current definition of this species is not accurate and that a redescription of it is necessary. In connection with this is the revalidation of another species, A. punctata (Kampen, 1913), considered to be a synonym of A. macrorhyncha. The third form is considered to be new to science, and it is described as such in this paper. This species occurs at an elevation of from 400 – 650 m above sea level in and on leaf litter primarily near streams in primary rainforest. The adult is 25 – 30 mm long. It is differentiated from related species in several body proportions and by its characteristic advertisement calls, and from the sympatric but obviously not syntopic A. macrorhyncha in the base sequences of the mitochondrial 12S rDNA- and 16S rDNA-genes as well.