''Kourerpeton'' 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 ...

dvinosauria Dvinosaurs are one of several new clades of Temnospondyl amphibians named in the phylogenetic review of the group by Yates and Warren 2000. They represent a group of primitive semi-aquatic to completely aquatic amphibians, and are known from t ...

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 ...

. Fossils of ''Kourerpeton'' were discovered in a window of a barber's shop in either Bisbee or

Mesa, Arizona Mesa ( ) is a city in Maricopa County, Arizona, Maricopa County, in the U.S. state of Arizona. It is the most populous city in the East Valley (Phoenix metropolitan area), East Valley section of the Phoenix Metropolitan Area. It is bordered by ...

. ''Kourerpeton'' was named in 1976, with the type and only species being ''K. bradyi''. It was originally assigned to the monotypic

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 ...

Kourerpetidae, which has been alternatively spelled Kourerpetontidae.

Age and location

Because it was not found ''in situ'', the provenance and age of ''Kourerpeton'' is unknown. The fossils are rumored to have been from the

Glen Rose Formation The Glen Rose Formation is a shallow marine to shoreline geological formation from the lower Cretaceous period exposed over a large area from South Central to North Central Texas. The formation is most widely known for the dinosaur footprints ...

near

Glen Rose, Texas Glen Rose is a city in and the county seat of Somervell County, Texas, United States. As of the 2012 census estimate, the city population was 2,502. History 19th century The area was first settled in 1849 by Charles Barnard, who opened a tradin ...

. Olson and Lammers (1976) discredited this idea because they noted that the Glen Rose Formation is

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

in age, and therefore not a likely source for a temnospondyl. Several studies have claimed that it is

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 ...

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a un ...

in age. Warren (1999) suggested that ''Kourerpeton'' is from an unknown

Guadalupian The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...

(

Middle Permian The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...

) to Early Triassic locality in

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, or possibly even from a locality outside North America. Milner and Sequeira (2004) have proposed that ''Kourerpeton'' may have been 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 ...

San Angelo Formation The San Angelo Formation is a geologic formation in Texas. It preserves fossils dating back to the Permian period. It is one of the geologically youngest formations to preserve fossils of pelycosaurs. Stratigraphy and age The San Angelo Formati ...

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 ...

, which has also been the source of the tupilakosaurid ''

Slaugenhopia ''Slaugenhopia'' is an extinct genus of dvinosaurian temnospondyl within the family Tupilakosauridae. Fossils have been found from the Early Permian San Angelo Formation in Texas. The type and only species, ''S. texensis'', was named in 1962. It ...

''. The San Angelo Formation is in close proximity to the Glen Rose Formation, occurring in a north-south belt across north-central Texas about west of Glen Rose.

Classification

''Kourerpeton'' is usually classified in its own dvinosaurian family, the Kourerpetidae. Milner and Sequeira (2004) suggested that ''Kourerpeton'' may be a tupilakosaurid based on similarities with the genus ''Slaugenhopia''. Like ''Slaugenhopia'', ''Kourerpeton'' possesses enlarged

postorbital The ''postorbital'' is one of the bones in vertebrate skulls which forms a portion of the dermal skull roof and, sometimes, a ring about the orbit. Generally, it is located behind the postfrontal and posteriorly to the orbital fenestra. In some ve ...

s and reduced

postfrontal The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

s, bones that form the portion of the

skull roof The skull roof, or the roofing bones of the skull, are a set of bones covering the brain, eyes and nostrils in bony fishes and all land-living vertebrates. The bones are derived from dermal bone and are part of the dermatocranium. In comparati ...

above the

eye sockets In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is , o ...

. Both ''Kourerpeton'' and ''Slaugenhopia'' possess incomplete-ring intercentra, which form the cenra of

vertebra The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic ...

e. The pleurocentra, which also comprise the centra, are slender and crescentic in both genera. Unlike ''Slaugenhopia'', ''Kourerpeton'' lacks an incisure, or notch, on the

pterygoid bone The pterygoid is a paired bone forming part of the palate of many vertebrates, behind the palatine bone In anatomy, the palatine bones () are two irregular bones of the facial skeleton in many animal species, located above the uvula in the th ...

of the

palate The palate () is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but in most other tetrapods, the oral and nasal cavities are not truly sepa ...

. In ''Slaugenhopia'', this incisure appears as a deep notch in the posterior margin of the central palate. In ''Kourerpeton'', the posterior edge of the skull table is strongly undulated, and has a medial concavity. This is unlike ''Slaugenhopia'', which has a relatively straight skull roof margin. Based on these differences, Milner and Sequeira (2004) considered ''Kourerpeton'' to be a primitive

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

-tupilakosaurid.

Notes

The only temnospondyl known from the Cretaceous is the chigutisaurid ''
Koolasuchus ''Koolasuchus'' is an extinct genus of brachyopoid temnospondyl in the family Chigutisauridae. Fossils have been found from Victoria, Australia and date back 120 Ma to the Aptian stage of the Early Cretaceous. ''Koolasuchus'' is the youngest kno ...
'', which was the latest surviving temnospondyl.

References

External links

''Kourerpeton''
in the

Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ...

{{Taxonbar, from=Q6434692 Dvinosaurs Permian temnospondyls of North America Permian Arizona Fossil taxa described in 1976

Age and location

Classification

See also

Notes

References

External links