Ectoganus ("outside brightness") is an extinct genus of taeniodonts from tribe Ectoganini within subfamily Stylinodontinae and family Stylinodontidae, that lived in North America from the Late Paleocene to Early Eocene.Schoch, Robert M. (1986.) "Systematics, functional morphology and macroevolution of the extinct mammalian order Taeniodonta." Bulletin of the Peabody Museum of Natural History, (42).S. G. Lucas, R. M. Schoch, and T. E. Williamson (1998.) "Taeniodonta". In C. M. Janis, K. M. Scott, and L. L. Jacobs (eds.), "Evolution of Tertiary Mammals of North America, Volume 1: Terrestrial Carnivores, Ungulates, and Ungulate like Mammals", Cambridge University Press, 703 pages
Description The microscopic structure of Ectoganus tooth enamel consists of a single main layer. The internal enamel feature known as the Hunter-Schreger band is present but is weakly developed. The enamel is composed of tightly packed rod-like structures (prisms) that show a keyhole-shaped cross-section and only a partially formed outer sheath. The underlying dentine — the main structural tissue of the tooth — follows a typical mammalian pattern. A relatively thick layer of cementum, the tissue that helps anchor teeth in the jaw, covers both the front and back surfaces of the teeth.
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