We describe a new species of Pristimantis from the vicinity of Puerto Almendras, ca. 17 km straight southwest, of Iquitos, Provincia Maynas, Region Loreto, Peru. With seven other species (P. carvalhoi, P. croceoinguinis, P divnae, P lirellus, P minutulus, P toftae, P. variabilis) from the Amazonian lowlands and lower eastern Andes in Peru, the new species shares a yellow groin and broadly expanded discs on fingers and toes. However, the new species can be distinguished, by the following combination of characters: snout-vent length 14.8 mm in the single male, 20.0-22.0 mm in females, strongly tubercular dorsal skin, absence of dorsolateral folds, areolate venter, indistinct discoidal fold, lack of tympanic membrane and annulus, lack of lateral fringes in fingers and toes, presence of ulnar and tarsal tubercles, presence of vocal slits in males, reddish brown or greenish brown dorsal coloration, pale grey to white venter with dark flecks or mottling, and. bright yellow groin in life. The new species is most similar to P. carvalhoi and. P. croceoinguinis. However, vocal slits are present in males of the new species (absent, in P. carvalhoi and P. croceoinguinis), and both P. carvalhoi and P. croceoinguinis lack a tubercle on the tip of the snout (present, in the new species). The new species is tentatively assigned, to the Pristimantis unistrigatus group. It. inhabits primary or disturbed lowland rainforest, along large rivers. © 2010 Deutsche Gesellschaft für Herpetologie und Terrarienkunde e.V. (DGHT), Rheinbach, Germany.