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// Workers AI · dad joke modeWhat did the coronoid bone say? I'm crowned king.

From Wikipedia, the free encyclopedia
(Redirected from Coronoid bones)
Mandible of Dimetrodon (top) and Labidosaurus (bottom). The coronoid is labeled as cor.

The coronoid is a bone present in the mandible of many non-mammalian vertebrates. It typically lies on the medial wall of each hemimandible.[1] Among its functions, it provides a lever arm for the attachment of jaw muscles.

Evolution

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In some actinoperygian fishes, the coronoid occurs near the anterior tip of the mandible and bears teeth.[2]

The coronoid is present in most sauropsids and amphibians.[3]

In early synapsids, the bone was present; it was progressively reduced during the evolution of mammals, and is absent in modern mammals. Its function has been taken over by the coronoid process of the dentary.[1]

In some animals, including some salamanders and parareptiles, the coronoid bears teeth.[4][5]

In some species, including the parareptile Delorhynchus and the fish Polypterus, multiple coronoid ossifications are present on each side.[5]

References

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  1. 1 2 Kardong, Kenneth (2015). Vertebrates: Comparative Anatomy, Function, Evolution (7th ed.). New York: McGraw-Hill. ISBN 978-0-07-802302-6.{{cite book}}: CS1 maint: date and year (link)
  2. Jollie, M. (1984). "Development of the head and pectoral skeleton of Polypterus with a note on scales (Pisces: Actinopterygii)". Journal of Zoology. 204 (4): 469–507. doi:10.1111/j.1469-7998.1984.tb02382.x. ISSN 1469-7998.
  3. Romer, A. S. (1956). Osteology of the Reptiles. Chicago: University of Chicago Press.
  4. Vassilieva, Anna B.; Smirnov, Sergei V. (2001). "Development and Morphology of the Dentition in the Asian Salamander, Ranodon sibiricus (Urodela: Hynobiidae)". Russian Journal of Herpetology. 8 (2): 105–116. doi:10.30906/1026-2296-2001-8-2-105-116. ISSN 1026-2296.
  5. 1 2 Haridy, Yara; Macdougall, Mark J; Reisz, Robert R (2018-11-01). "The lower jaw of the Early Permian parareptile Delorhynchus, first evidence of multiple denticulate coronoids in a reptile". Zoological Journal of the Linnean Society. 184 (3): 791–803. doi:10.1093/zoolinnean/zlx085. ISSN 0024-4082.