Dinnebitodon

''Dinnebitodon'' is an extinct genus of advanced herbivorous cynodonts of the early Jurassic period. It has only been found in the Kayenta Formation in northeastern Arizona. It closely resembles the related genus ''Kayentatherium'' from the same formation. It is set apart by differences in the dentition, while resembling in most other respects.

Description

''Dinnebitodon'' (meaning "Dinnebito (Wash) tooth"Sues, Hans-Dieter. 1986. ''Dinnebitodon amarali'', a new Tritylodontid (Synapsida) from the lower Jurassic of western North America. Journal of Paleontology v. 60 no. 3. pp. 758-762), was a small quadrupedal animal, with a head in length, belonging to the herbivorous Tritylodontidae family. The description of ''Dinnebitodon'' does not give details on the structure of the body other than to say it was similar to ''Kayentatherium''.

Skull and jaw

The majority of the remains so far recovered and assigned to the genus ''Dinnebitodon'' are skull and jaw material. These show that ''Dinnebitodon'' had a skull long and unique in form. There are three incisors on each side of the upper jaw, with the second incisor being large and well developed at by . There are five postcanine teeth in the upper jaw that would have been functional when ''Dinnebitodon'' was alive, with a sixth possibly erupting later in the animal's life. The postcanine teeth resemble rounded-off squares with three rows of cusps on their occlusal surfaces. The teeth are notably different from the other two named Kayenta tritylodonts, ''Kayentatherium'' and ''Oligokyphus''.

Habitat

The Kayenta Formation was deposited in an environment of braided rivers and dune fields,Harshbarger, J., Repenning, C., and Irwin, J. 1957. Stratigraphy of the uppermost Triassic and the Jurassic rocks of the Navajo Country. United States Geological Survey Professional Paper, 291: 1-74 similar to northern Senegal today. ''Dinnebitodon'' was a terrestrial animal, living in the "Silty Facies" of the Kayenta Formation, which would have represented an interdunal river deposit. The teeth resemble those of modern animals that also feed on seeds and nuts,Sovak, J. 1999. Before the Dinosaurs (Coloring Book). Dover Publications. p.43 suggesting that perhaps ''Dinnebitodon'' fed on similar foods present during the early Jurassic Period. Considering it was living alongside its close relative ''Kayentatherium'', some niche partitioning of the resources would have been necessary in order to avoid being outcompeted for a food source. This might explain why two similar looking animals have different dentition.

Fossil finds

''Dinnebitodon'' fossils were first discovered by William Amaral (for whom the species is named) in 1978. Remains are housed at Harvard's Museum of Comparative Zoology and at the Museum of Northern Arizona.

See also

*Kayenta Formation
*''Oligokyphus''
*''Kayentatherium''

References

{{Taxonbar, from=Q5278394

Prehistoric cynodont genera
Jurassic synapsids
Mesozoic synapsids of North America
Kayenta Formation
Tritylodontids
Fossil taxa described in 1986