Adelophryne pachydactyla is a species of frog in the family Eleutherodactylidae. It is endemic to the coastal area of south-central Bahia state, Brazil. Some specimens first identified as A. pachydactyla have later been found to represent a new species, Adelophryne mucronatus ; the two species can occur in sympatry. The specific name pachydactyla is derived from Greek pachys (=thick) and daktylos (=finger), referring to the thick, short, swollen fingers of this frog.
Adelophryne pachydactyla was described based on a single specimen, the holotype. It is an adult male measuring 11 mm (0.4 in) in snout–vent length, and with a subgular vocal sac. The head is slightly longer than it is wide. The snout is rounded. The tympanic annulus is incomplete, obscured by skin in its upper parts. There is no supra-tympanic fold and the canthus rostralis is indistinct. The limbs are relatively short. The fingers are short and have swollen, subdigital pads but no discs. The toes have small discs and no webbing. The body is blackish brown with grey spots dorsally and black under. The iris is reddish.
