''Oradectes'' (meaning "margin biter", from Latin ''ora'' (margin) and ''dectes'' (biter)) 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 ...

diadectid Diadectidae is an extinct family of early tetrapods that lived in what is now North America and Europe during the Late Carboniferous and Early Permian in Asia during the Late Permian. They were the first herbivorous tetrapods, and also the first ...

reptiliomorph Reptiliomorpha (meaning reptile-shaped; in PhyloCode known as ''Pan-Amniota'') is a clade containing the amniotes and those tetrapods that share a more recent common ancestor with amniotes than with living amphibians ( lissamphibians). It was de ...

. It is known from a single partial skeleton collected 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 ...

Cutler Formation The Cutler Formation or Cutler Group is a rock unit that is exposed across the U.S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian epoch. Descript ...

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

, ''O. sanmiguelensis'', was originally named as a species of ''

Diadectes ''Diadectes'' (meaning ''crosswise-biter'') is an extinct genus of large reptiliomorphs or synapsids that lived during the early Permian period (Artinskian-Kungurian stages of the Cisuralian epoch, between 290 and 272 million years ago). ''Diade ...

'' in 1965. It was given its own genus in 2010.

Description

The only material belonging to ''Oradectes'' is a partial skeleton known as MCZ 2989. This skeleton includes a complete skull, neck vertebrae, a partial pectoral girdle, the right forelimb, and some ribs. The skull is robust with spade-shaped teeth lining the jaws. The front teeth of the lower jaw protrude outward. A ventral border of the Meckelian fenestra of the lower jaw formed entirely from the

splenial The splenial is a small bone in the lower jaw of reptiles, amphibians and birds, usually located on the lingual side (closest to the tongue) between the angular and surangular The suprangular or surangular is a jaw bone found in most land ver ...

bone is a distinguishing feature of ''Oradectes'' found in no other diadectid.

Classification

''Oradectes sanmiguelensis'' was described by Lewis and Vaughn (1965) as a species of ''Diadectes'', ''D. sanmiguelensis''. In a 2005 phylogenetic study of diadectids, ''D. sanmiguelensis'' was found to be one of the most basal diadectids and was placed far from a clade containing most of the other species of ''Diadectes''. A 2010 analysis came up with the same results and assigned ''D. sanmiguelensis'' to the new genus ''Oradectes''. Below is a

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

from the 2010 study showing the phylogenetic position of ''Oradectes'':

References

Diadectids Cisuralian tetrapods of North America Permian Colorado Paleontology in Colorado Fossil taxa described in 2010 {{Permian-animal-stub