It is found in the Amazon Basin in Colombia (Amazonas and Vaupés Departments[5]), Ecuador (Pastaza Province[4]), Peru, and western Brazil.

[3] Adelophryne adiastola are tiny frogs: based on the type series consisting of three males and a female, males measure 13–13.7 mm (0.51–0.54 in) and the female 13.9 mm (0.55 in) in snout–vent length.

The toes have circumferentially grooved, asymmetrically pointed discs.

[2] Adelophryne adiastola is a terrestrial frog inhabiting primary and secondary lowland tropical moist forests at elevations up to 300 m (980 ft) above sea level.

[1][4][5] The female paratype had ingested a small harvestman of the family Sironidae.