Lumkuia is an extinct genus

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 probainognathia

Probainognathia

The Probainognathians are one of the two major clades of the infraorder Eucynodontia, the other being Cynognathians. They were mostly carnivorous, though some species may have evolved omnivorous traits. The Probainognathia form into four groups: Probainognathidae, Chiniquodontidae,...

n cynodont

Cynodont

Cynodontia or cynodonts are a taxon of therapsids which first appeared in the Late Permian and were eventually distributed throughout all seven continents by the Early Triassic . This clade includes modern mammals and their extinct close relatives. They were one of the most diverse groups of...

. It is the earliest and most basal

Basal (phylogenetics)

In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...

 known member of Probainognathia, with fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s being found from the Lystrosaurus Assemblage Zone

Lystrosaurus Assemblage Zone

The Lystrosaurus Assemblage Zone is a geological stratum and a faunal zone of the Beaufort Group, of the South African Karoo. The name refers to Lystrosaurus, a genus of mammal-like reptile, a dominant life form of the Early Triassic Period, whose fossils have been found in that structure....

 of the Beaufort Group

Beaufort Group

The Beaufort Group is the third of the main subdivisions of the Karoo Supergroup of geological strata in Southern Africa. It follows conformably after the Ecca Group and consists essentially of sandstones and shales, deposited in the Karoo Basin from the Middle Permian to the early part of the...

 in the South African Karoo Basin

Karoo

The Karoo is a semi-desert region of South Africa. It has two main sub-regions - the Great Karoo in the north and the Little Karoo in the south. The 'High' Karoo is one of the distinct physiographic provinces of the larger South African Platform division.-Great Karoo:The Great Karoo has an area of...

 that date back to the early Middle Triassic

Middle Triassic

In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided. It spans the time between 245 ± 1.5 Ma and 228 ± 2 Ma...

. Lumkuia is not as common as other cynodonts from the same locality such as Diademodon

Diademodon

Diademodon is an vegetarian extinct genus of therapsid. It was about the size of a small cow. Fossils of the Diademodon tetragonus were found in levels of the Rio Seco de la Quebrada geological formation in Mendoza Province, Argentina....

and Trirachodon

Trirachodon

Trirachodon is an extinct genus of tritylodontoid cynodont. Fossils have been found from the Cynognathus Assemblage Zone of the Beaufort Group in South Africa, dating back to the Early and Middle Triassic.-Description:...

. Previously, early probainognathians were only known from younger strata in South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 that were deposited in the late Middle and Late Triassic

Late Triassic

The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

. The genus has been placed in its own 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...

, Lumkuiidae.

The postcanines are similar to the later chiniquodontids

Chiniquodontidae

Chiniquodontidae is a family of meat-eating advanced mammal-like reptiles that lived during the Upper Triassic of South America and perhaps Europe. A further possible representative, Aleodon, has been identified from the Middle Triassic of Africa...

, but the secondary palate is quite short in comparison, and the genus lacks the angulation of the ventral cranial margin seen in chiniquodontids. Lumkuia can be seen as more derived than other contemporary cynodonts such as Cynognathus

Cynognathus

Cynognathus crateronotus was a meter-long predator of the Early to Middle Triassic. It was among the more mammal-like of the Synapsids, a member of a grouping called Eucynodontia. The genus Cynognathus had an almost worldwide distribution...

with the crowns of its teeth high and narrow and having inwardly curving tops. The genus was named in 2001 on the basis of the holotype specimen BP/1/2669, which can now be found at the Bernard Price Institute in Johannesburg

Johannesburg

Johannesburg also known as Jozi, Jo'burg or Egoli, is the largest city in South Africa, by population. Johannesburg is the provincial capital of Gauteng, the wealthiest province in South Africa, having the largest economy of any metropolitan region in Sub-Saharan Africa...

, South Africa.

External links

• Lumkuia in the Paleobiology Database
  Paleobiology 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...