Biology:Kangnasaurus

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Short description: Extinct genus of dinosaurs

Kangnasaurus
Temporal range: Early Cretaceous, 120 Ma
Iziko Thigh bone kangnasaurus.JPG
Thigh bone of cf. Kangnasaurus
Scientific classification edit
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Ornithischia
Clade: Ornithopoda
Family: Dryosauridae
Genus: Kangnasaurus
Haughton, 1915
Species:
K. coetzeei
Binomial name
Kangnasaurus coetzeei
Haughton, 1915

Kangnasaurus (meaning "Farm Kangnas lizard") is a genus of iguanodontian ornithopod dinosaur found in supposedly Early Cretaceous rocks of South Africa . It is known from a tooth and possibly some postcranial remains found in the early-Aptian Kalahari Deposits Formation.[1] It was probably similar to Dryosaurus.

Discovery and naming

Holotype tooth of K. coetzeei (SAM 2732) as seen from three different angles; figured from Haughton (1915)[2]

Kangnasaurus was named in 1915 by Sidney H. Haughton. The type species is Kangnasaurus coetzeei. The generic name refers to the Kangnas farm; the specific name to the farmer, Coetzee. Kangnasaurus is based on holotype SAM 2732, a tooth found at a depth of 34 metres in a well at Farm Kangnas, in the Orange River valley of northern Cape Province, South Africa .[2] The age of these rocks, conglomerates in an ancient crater lake, is unclear; they are thought to be from the Early Cretaceous (probably early-Aptian).[3] Haughton thought SAM 2732 was a tooth from the upper jaw, but Michael Cooper reidentified it as a lower jaw tooth in 1985.[4] This had implications for its classification: Haughton thought the tooth was that of an iguanodontid,[2] while Cooper identified it as from an animal more like Dryosaurus, a more basal ornithopod.[4]

Haughton described several other fossils as possibly belonging to Kangnasaurus. These include five partial thigh bones, a partial thigh bone and shin bone, a partial metatarsal, a partial shin and foot, vertebrae, and unidentified bones. Some of the bones apparently came from other deposits, and Haughton was not certain that they all belonged to his new genus.[2] Cooper was also not certain, but described the other specimens as if they did belong to Kangnasaurus.[4]

Classification

Kangnasaurus is usually regarded as dubious,[5][6] although a 2007 review of dryosaurids by Ruiz-Omeñaca and colleagues retained it as potentially valid, differing from other dryosaurids by details of the thigh bone.[3] Like other basal iguanodontians, it would have been a bipedal herbivore.[6]

At least two recent studies have found it to be an elasmarian instead of a dryosaurid.[7][8]

References

  1. "Table 19.1," in Weishampel, et al. (2004). Page 417.
  2. Jump up to: 2.0 2.1 2.2 2.3 Haughton, Sidney H. (1915). "On some dinosaur remains from Bushmanland". Transactions of the Royal Society of South Africa 5: 259–264. doi:10.1080/00359191509519723. https://zenodo.org/record/1430389. 
  3. Jump up to: 3.0 3.1 Ruiz-Omeñaca, José Ignacio; Pereda Suberbiola, Xavier; Galton, Peter M. (2007). "Callovosaurus leedsi, the earliest dryosaurid dinosaur (Ornithischia: Euornithopoda) from the Middle Jurassic of England". in Carpenter Kenneth. Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs. Bloomington and Indianapolis: Indiana University Press. pp. 3–16. ISBN 978-0-253-34817-3. 
  4. Jump up to: 4.0 4.1 4.2 Cooper, Michael R. (1985). "A revision of the ornithischian dinosaur Kangnasaurus coetzeei Haughton, with a classification of the Ornithischia". Annals of the South African Museum 95 (8): 281–317. 
  5. Sues, Hans-Dieter; Norman, David B. (1990). "Hypsilophodontidae, Tenontosaurus, Dryosauridae". in Weishampel, David B.. The Dinosauria (1st ed.). Berkeley: University of California Press. pp. 498–509. ISBN 0-520-06727-4. 
  6. Jump up to: 6.0 6.1 Norman, David B. (2004). "Basal Iguanodontia". in Weishampel, D.B.. The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 413–437. ISBN 0-520-24209-2. 
  7. Rozadilla, Sebastián; Agnolín, Federico Lisandro; Novas, Fernando Emilio (2019-12-17). "Osteology of the Patagonian ornithopod Talenkauen santacrucensis (Dinosauria, Ornithischia)". Journal of Systematic Palaeontology 17 (24): 2043–2089. doi:10.1080/14772019.2019.1582562. ISSN 1477-2019. https://www.researchgate.net/publication/332843404. 
  8. "A new phylogeny of cerapodan dinosaurs". Historical Biology 33 (10): 2335–2355. 2020. doi:10.1080/08912963.2020.1793979. 

Wikidata ☰ Q633747 entry