Distribution
Noblella pygmaea is endemic to Peru. It is known from two locations in southern Peru, and is found at elevations of 2,380–3,485 metres (7,808–11,434 ft). The species inhabits puna grasslands, montane scrubland, and cloud forest environments.
Noblella pygmaea is syntopic with Bryophryne nubilosus.
Description
In females, the snout-vent length is 11.3–12.4 millimetres (0.44–0.49 in). In males, the snout-vent length is 10.3–11.1 millimetres (0.41–0.44 in). When discovered, the species was the smallest known Andean frog, and is one of the world's smallest frogs.
The back is dark brown, dark grey, and tan, with a pale grey or tan stripe from the upper eyelid to the thighs. The throat, chest, belly, and thighs are reddish brown, with small grey spots. The flanks may be dark brown or pale grey. The back has tubercles, which are denser on the back of the body.
The head is narrower than the body. A tympanum is present. The vomer lacks a dentigerous process. The choanae are small and rounded. The nostrils do not protrude. The canthus is dorsally curved, and rounded in profile. The upper eyelid has small tubercles. The iris is dark brown, with gold spots. The pupil is surrounded by an orange ring.
Noblella pygmaea lacks nuptial pads.
Noblella pygmaea is mainly terrestrial, and is assumed to undergo direct development.
