Pristimantis w-nigrum, also known as the Zurucuchu robber frog or w rainfrog, is a species of frog in the family Strabomantidae. It is found on both Pacific and Amazonian slopes of the Andes in Colombia, Ecuador, and northern Peru.[1] The species is divided to at least eight clades that are genetically highly divergent but morphologically similar; it may be a species complex.[2]
Pristimantis w-nigrum males measure 29mm47mm in snout–vent length and females measure 44mm57mm. Live specimens are easily recognized by a colour pattern of yellow with black markings on the groin, anterior and posterior surfaces of thighs, and concealed shank. Tympanum is distinct.[3]
The natural habitats of Pristimantis w-nigrum are cloud forest and sub-páramo, but it occurs also in deforested and disturbed areas. It is a nocturnal species[3] that can be found perched on vegetation up to 3 metres above ground; during the day it can be found on fallen leaves. It is a common species although it has declined in many areas.