Material referred to the taxon comes from the Archer City, Nocona, and Petrolia Formations and was collected between 1934 and 1952 by parties led by A.S. Romer, L.I.

Schoch & Milner (2014) separated the former 'Acheloma whitei' from P. pricei, distinguishing it by the shorter and more rounded external naris and an otic notch that was not slit-like.

Dilkes (1990) diagnosed Phonerpeton by the semilunar curvature of the squamosal, doming of the parietals along the midline, a closed basicranial joint with a clear suture between the pterygoid and the basipterygoid process of the parasphenoid (the basicranial joint), an unossified sphenethmoid, long and slender mid-dorsal ribs, a radius with a semicircular cross section, and a ridge along the anterolateral edge of the ulna.

He differentiated it from Acheloma by the large and posteriorly open otic notch, a posterodorsal process of the quadrate consisting of two sheets of bone separated by a poorly ossified region, a semilunar curvature of the squamosal, and an unfused basicranial joint.

Phylogeny below from Polley & Reisz (2011):[4] Sclerocephalus haeuseri Micromelerpeton credneri Micropholis stowi Eoscopus lockardi Cacops morrisi Phonerpeton pricei Acheloma cumminsi Acheloma dunni Actiobates peabodyi Ecolsonia cutlerensis Anconastes vesperus Tambachia trogallas