The Northern Darwin's frog or 'Sapito vaquero' (Cowboy little frog in Spanish) inhabits the native forests across the coastal mountain range of central and southern Chile, from Zapallar to Concepción. This species was described for the first time in 1902 as Heminectes rufus, although its taxonomic validity was largely contested. Only in 1975, this species was taxonomically re-validated and classified within the genus Rhinoderma.In contrast to the Southern Darwin's frog, the males of this frog btood the tadpoles inside their vocal sacs only for a short period of time, after this they are expelled into the ridge of a creek to complete their larval development and metamorphosis (transformation from tadpole to froglet). Other characteristic of this species is the presence of well-developed interdigital membranes between all the toes of the hindlimbs, an adaptation that could be useful for swimming.Unfortunately, the Northern Darwin's frog has not been observed since 1981, and it is currently classified as a Critically Endangered (Probably Extinct) species by the IUCN red list. If this is true, it would be the first chilean animal that find the extinction in contemporary times.