''Phonerpeton'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

dissorophoid Dissorophoideans are a clade of medium-sized, temnospondyl amphibians that appeared during the Moscovian in Euramerica, and continued through to the Late Permian and the Early Triassic of Gondwana. They are distinguished by various details of th ...

temnospondyl Temnospondyli (from Greek language, Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order (biology), order of small to giant tetrapods—often considered Labyrinthodontia, primitive amphi ...

within the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Trematopidae Trematopidae is a family of dissorophoid temnospondyl spanning the late Carboniferous to the early Permian. Together with Dissorophidae, the family forms Olsoniformes, a clade comprising the medium-large terrestrial dissorophoids. Trematopids a ...

that is known from the early

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

of Texas.

History of study

''Phonerpeton'' was first named by Dilkes (1990), with ''Phonerpeton pricei'' as the only species. The genus name comes from the Greek words '''phonos''' (murderous) and '''herpeton''' (creeper). The holotype of ''P. pricei'' was previously described by Olson (1941) as ''Acheloma pricei''. Dilkes also synonymized this species with ''Acheloma whitei'', which was also described by Olson (1941). 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. Price, and R.V Witter. 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. They restricted ''P. pricei'' to the specimens from the Archer City Formation and ''P. whitei'' to the specimens from the Petrolia Formation.

Anatomy

''Phonerpeton'' is represented only by relatively small specimens compared to the much larger ''Acheloma''. 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. Schoch & Milner (2014) retained only the absence of a slit-like notch (which is found in ''Acheloma'') in the diagnosis.

Phylogeny

''Phonerpeton'' is typically recovered as being most closely related to the other long-snouted trematopid from North America, ''Acheloma''. Phylogeny below from Polley & Reisz (2011):

References

{{Taxonbar, from=Q7187210 Dissorophids Trematopids Cisuralian temnospondyls of North America Fossil taxa described in 1990 Prehistoric amphibian genera