Kayentachelys aprix

fossil turtle

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July 17, 2026

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Kayentachelys aprix was a fossil turtle species that lived during the Late Jurassic period, approximately 150 million years ago. It is considered the oldest known turtle from North America and is believed to be a member of the Cryptodira suborder, which includes modern turtles with hidden necks.1

The evolution of turtles dates back to the Late Permian Epoch, with early forms lacking fully developed shells. Over time, structures like the plastron and carapace evolved from modified ribs and vertebrae. Kayentachelys aprix represents a significant point in this evolutionary history, showcasing the development of turtle anatomy.1

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turtle
Origin and evolution
…the other turtle suborder, Cryptodira, Kayentachelys aprix of the Late Jurassic (some 150 million years ago) is almost assuredly a cryptodire; it is also the oldest known North American turtle. Other cryptodires are known from the Late Jurassic, although they are not representative of existing families. The largest known turtles…
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…the other turtle suborder, Cryptodira, Kayentachelys aprix of the Late Jurassic (some 150 million years ago) is almost assuredly a cryptodire; it is also the oldest known North American turtle. Other cryptodires are known from the Late Jurassic, although they are not representative of existing families. The largest known turtles…
Read More