''Parioxys'' 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 ...
of
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 ...
amphibian from the
Early Permian 01 or '01 may refer to:
* The year 2001, or any year ending with 01
* The month of January
* 1 (number)
Music
* '01 (Richard Müller album), 01'' (Richard Müller album), 2001
* 01 (Son of Dave album), ''01'' (Son of Dave album), 2000
* 01 (Urban ...
of
Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
.
History of study
The type species, ''Parioxys ferricolus'', was named in 1878 by American paleontologist
Edward Drinker Cope based on two badly preserved skulls that were collected from the early Permian Texas red-beds. Egyptian paleontologist Youssef S. Moustafa, described new material of ''P. ferricolus'' from other localities in Texas.
This taxon was recently redescribed by Schoch & Sues (2022). Moustafa also described another species, ''P. romeri'', on the basis of an isolated humerus, but this was regarded as being indeterminate. A second definitive species, ''P. bolli'', was described by Canadian paleontologist
Robert Carroll in 1964. This taxon is only known from postcranial material.
Relationships
''Parioxys'' was historically considered to be closely related to
eryopoids, more specifically the well-known ''
Eryops megalocephalus'', which was collected from the same locality as the type material of ''P. ferricolus''. Cope himself listed ''P. ferricolus'' as a species of ''Eryops,'' possibly because he considered it to be a juvenile specimen of ''Eryops.'' It was shortly revived as a distinct genus with a suggestion that the original specimen's described by Cope might have been inadvertently described as other taxa by other authors, but its affinities continued to be debated, with some suggestions that it might instead belong to the
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 ...
. Moustafa (1955a) placed ''Parioxys'' in its own family and suggested that it was related to the
Dissorophidae
Dissorophidae is an extinct family of medium-sized, temnospondyl amphibians that flourished during the late Carboniferous and early Permian periods. The clade is known almost exclusively from North America.
History of study
Dissorophidae is a ...
.
Schoch & Milner (2014) placed ''Parioxys'' within Dissorophidae based on personal observations of further preparation of historic material, although this has not been tested in a phylogenetic analysis due to the poor quality of much of the material.
The most recent revision by Schoch & Sues (2022) tested the position of ''P. ferricolus'' in a dissorophoid matrix and recovered it as a
eucacopine dissorophid of closest relationship to the middle Permian ''
Kamacops
''Kamacops'' is a genus of dissorophid temnospondyls known from the Middle to Late Permian of Russia that was described by Yuri Gubin in 1980. It is known from a single species, ''Kamacops acervalis,'' material of which is currently reposited ...
''. They list the following features as features shared between this species and ''Kamacops'' and not with ''Cacops'': (1) smaller interpterygoid vacuities, resulting from the medial expansion of palatine and pterygoid (condition more extreme in K. acervalis); (2) the enlarged vomer with the posteriorly elongated, slit-like choana; and (3) the absence of an internarial fenestra.
References
{{Taxonbar, from=Q16587182
Cisuralian temnospondyls of North America
Prehistoric amphibian genera