Kourerpeton
Encyclopedia
Kourerpeton is an extinct genus
of dvinosauria
n temnospondyl. Fossils of Kourerpeton were discovered in a window of a barber's shop in either Bisbee
or Mesa, Arizona
. Kourerpeton was named in 1976, with the type
and only species being K. bradyi. It was originally assigned to the monotypic family
Kourerpetidae, which has been alternatively spelled Kourerpetontidae.
near Glen Rose, Texas
. Olson and Lammers (1976) discredited this idea because they noted that the Glen Rose Formation is Cretaceous
in age, and therefore not a likely source for a temnospondyl. Several studies have claimed that it is Permian
or Early Triassic
in age. Warren (1999) suggested that Kourerpeton is from an unknown Guadalupian (Middle Permian) to Early Triassic locality in North America
, or possibly even from a locality outside North America. Milner and Sequeira (2004) have proposed that Kourerpeton may have been from the Early Permian San Angelo Formation in Texas
, which has also been the source of the tupilakosaurid
Slaugenhopia
. The San Angelo Formation is in close proximity to the Glen Rose Formation, occurring in a north-south belt across north-central Texas about 80 miles (128.7 km) west of Glen Rose.
s and reduced postfrontals, bones that form the portion of the skull roof
above the eye sockets
. Both Kourerpeton and Slaugenhopia possess incomplete-ring intercentra, which form the cenra of vertebrae. 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 of the palate
. 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-tupilakosaurid.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of dvinosauria
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 the Late Carboniferous to the Early Triassic, being most...
n temnospondyl. Fossils of Kourerpeton were discovered in a window of a barber's shop in either Bisbee
Bisbee, Arizona
Bisbee is a city in Cochise County, Arizona, United States, 82 miles southeast of Tucson. According to 2005 Census Bureau estimates, the population of the city was 6,177...
or Mesa, Arizona
Mesa, Arizona
According to the 2010 Census, the racial composition of Mesa was as follows:* White: 77.1% * Hispanic or Latino : 26.54%* Black or African American: 3.5%* Two or more races: 3.4%* Native American: 2.4%...
. Kourerpeton was named in 1976, with the type
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
and only species being K. bradyi. It was originally assigned to the monotypic family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
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 FormationGlen 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...
near Glen Rose, Texas
Glen Rose, Texas
Glen Rose is a city in Somervell County, Texas, United States. It is the county seat of Somervell County. As of the 2010 census, the city population was 2,444. Glen Rose is part of the Granbury micropolitan area.-19th century:...
. Olson and Lammers (1976) discredited this idea because they noted that the Glen Rose Formation is Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
in age, and therefore not a likely source for a temnospondyl. Several studies have claimed that it is Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
or Early Triassic
Early Triassic
The Early Triassic is the first of three epochs of the Triassic period of the geologic timescale. It spans the time between 251 ± 0.4 Ma and 245 ± 1.5 Ma . Rocks from this epoch are collectively known as the Lower Triassic, which is a unit in chronostratigraphy...
in age. Warren (1999) suggested that Kourerpeton is from an unknown Guadalupian (Middle Permian) to Early Triassic locality in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, or possibly even from a locality outside North America. Milner and Sequeira (2004) have proposed that Kourerpeton may have been from the Early Permian San Angelo Formation in Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, which has also been the source of the tupilakosaurid
Tupilakosauridae
Tupilakosauridae is an extinct family of dvinosaurian temnospondyls. It contains the genera Slaugenhopia, Thabanchuia, Tupilakosaurus, and possibly Kourerpeton. Tupilakosaurs are known from Texas, Greenland, Russia, and France. The earliest tupilakosaur, Slaugenhopia, is Early Permian in age while...
Slaugenhopia
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 may be closely related to the dvinosaur Kourerpeton...
. The San Angelo Formation is in close proximity to the Glen Rose Formation, occurring in a north-south belt across north-central Texas about 80 miles (128.7 km) 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 postorbitalPostorbital
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 vertebrates, the postorbital is fused with the postfrontal...
s and reduced postfrontals, bones that form the portion of the skull roof
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, hence the alternative name dermatocranium...
above the eye sockets
Orbit (anatomy)
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...
. Both Kourerpeton and Slaugenhopia possess incomplete-ring intercentra, which form the cenra of vertebrae. 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 of the palate
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 separate. The palate is divided into two parts, the anterior...
. 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-tupilakosaurid.
See also
- Prehistoric amphibian
- List of prehistoric amphibians
External links
- Kourerpeton in the Paleobiology DatabasePaleobiology Database' is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.-History:The Paleobiology Database was founded in 2000. It has been funded by the National Science Foundation and the Australian Research Council...