Denticle (tooth feature)

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Denticles, also called serrations, are small bumps on a tooth that serve to give the tooth a serrated edge. In paleontology, denticle characteristics such as size and density (denticles per unit distance) are used to describe and classify fossilized teeth, especially those of dinosaurs. Denticles are also present on the teeth of varanoid lizards, sharks, and mammals. [1] The term is also used to describe the analogous radular teeth of mollusks. [2] [3] [4]

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Diodorus is a genus of silesaurid dinosauromorph that lived during the Late Triassic in what is now Morocco. Fossils were discovered in the Timezgadiouine Formation of the Argana Basin, and were used to name the new genus and species Diodorus scytobrachion. The genus name honors the mythological king Diodorus and the ancient historian Diodorus Siculus; the specific name is ancient Greek for 'leathery arm' and also honors the mythographer Dionysius Scytobrachion. The holotype specimen is a partial dentary bone (front of the lower jaw), and assigned specimens include isolated teeth, two humeri (upper arm bones), a metatarsal (foot bone), and femur (thigh bone).

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Pegomastax is a genus of heterodontosaurid dinosaur that lived during the Early Jurassic of South Africa. The only known specimen was discovered in a 1966-1967 expedition in Transkei District of Cape Province, but wasn't described until 2012 when Paul Sereno named it as the new taxon Pegomastax africana. The genus name is derived from the Greek for "strong jaw", and the species name describes the provenance of Africa; it was originally spelled africanus, was corrected to africana to align with the gender of the genus name.

This glossary explains technical terms commonly employed in the description of dinosaur body fossils. Besides dinosaur-specific terms, it covers terms with wider usage, when these are of central importance in the study of dinosaurs or when their discussion in the context of dinosaurs is beneficial. The glossary does not cover ichnological and bone histological terms, nor does it cover measurements.

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Chenanisaurus is a genus of predatory abelisaurid dinosaur, with a single known species C. barbaricus. It comes from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa. The animal is known from a holotype, consisting of a partial jaw bone, and several isolated teeth found in the same beds. Chenanisaurus is one of the largest members of the Abelisauridae, and one of the last, being a contemporary of the North American Tyrannosaurus. It would have been among the dinosaur species wiped out by the Chicxulub asteroid impact and the Cretaceous-Paleogene mass extinction that followed.

References

  1. Smith, Joshua B.; Vann, David R.; Dodson, Peter (August 2005). "Dental morphology and variation in theropod dinosaurs: Implications for the taxonomic identification of isolated teeth". The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology. 285A (2): 699–736. doi: 10.1002/ar.a.20206 . PMID   15986487.
  2. Lowenstam, H.A. (1962). "Magnetite in Denticle Capping in Recent Chitons (Polyplacophora)". GSA Bulletin. 73 (4): 435–438. doi:10.1130/0016-7606(1962)73[435:MIDCIR]2.0.CO;2.
  3. "Glossary of Terminology and Acronyms /Abbreviations: D". Coral Reef Information System. NOAA . Retrieved 18 October 2022. Archived as PDF.
  4. Smith, M.R. (2012). "Mouthparts of the Burgess Shale fossils Odontogriphus and Wiwaxia: implications for the ancestral molluscan radula". Proceedings of the Royal Society B. 279 (1745): 4287–4295. doi: 10.1098/rspb.2012.1577 . PMC   3441091 .