''Daqingshanodon'' is an extinct genus of

dicynodont Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivores that typically bore a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, t ...

therapsid from the

Late Permian Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Groh ...

Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an Autonomous regions of China, autonomous region of China. Its border includes two-thirds of the length of China's China–Mongolia border, border with the country of Mongolia. ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

. The

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

''D. limbus'' was described in 1989 from a single skull found in the

Naobaogou Formation The Naobaogou Formation is a geological formation in the Daqing Mountains of China. It is likely of Lopingian (Late Permian) age. It consists of three rhythms of sediment, labeled members I-III primarily of purple siltstone, but each with a thick ...

. ''Daqingshanodon'' belongs to a group of dicynodonts called cryptodonts. It is the smallest known cryptodont, and the only one known from China. Like other cryptodonts, it has a pair of rounded nasal bosses above its nostrils and a ridge of bone on the upper jaw called the postcaniniform process. ''Daqingshanodon'' has a pair of elongated, recurved tusks extending from its beak-like snout. It is distinguished from other dicynodonts by the presence of a distinct ridge running along the side of the skull from below the eye socket to the area around the tusks. The skull of ''Daqingshanodon'' is less than long, yet this specimen is thought to have been an adult on the basis of its well-developed nasal bosses. In his 1998 study of dicynodont

biogeography Biogeography is the study of the species distribution, distribution of species and ecosystems in geography, geographic space and through evolutionary history of life, geological time. Organisms and biological community (ecology), communities o ...

, paleontologist Spencer G. Lucas synonymized ''Daqingshanodon'' with '' Dicynodon'', forming the species ''Dicynodon limbus''. Most of the features used to distinguish ''Daqingshanodon'' as a distinct genus were also seen in specimens of ''Dicynodon''. In 2011, a study of ''Dicynodon'' species included ''D. limbus'' in its

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis. ''D. limbus'' was placed among the cryptodonts, which are only distantly related to ''Dicynodon''. With this phylogenetic placement, the genus ''Daqingshanodon'' was reinstated for ''D. limbus''. Below is a

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

from the 2011 analysis:

References

{{Taxonbar, from=Q5221837 Bidentalia Lopingian synapsids of Asia