Phrynopus AmphibiaWeb keeps "Noblella" in Strabomantidae/Strabomantinae, a family/subfamily no longer recognized by the Amphibian Species of the World. "Phrynopus" are small to medium-sized frogs, from snout–vent length in "Phrynopus auriculatus" to in "Phrynopus kauneorum". Head is narrower than the body. Differentiated tympanic membrane and tympanic annulus are usually absent, except in "Phrynopus auriculatus" and "Phrynopus peruanus", two basal species. Dorsum is smooth to pustulate. Venter is smooth or areolate. There are 26 species in this genus: Phrynopus Phrynopus is a genus of frogs of the Craugastoridae family. Their common name is Andes frogs. They are endemic to Peru and inhabit the
Tympanic duct attached to the basilar membrane and their stereocilia embedded in the tectorial membrane. The movement of the basilar membrane compared to the tectorial membrane causes the stereocilia to bend. They then depolarise and send impulses to the brain via the cochlear nerve. This produces the sensation of sound. Tympanic duct The tympanic duct or scala tympani is one of the perilymph-filled cavities in the inner ear of the human. It is separated from the cochlear duct by the basilar membrane, and it extends from the round window to the helicotrema, where it continues as vestibular duct. The purpose of the