Archelon

Archelon ischyros · Archelon was the largest turtle ever documented, an extinct marine giant that lived in the Late Cretaceous seaway of what is now North America.

It lived about 80.2 to 74.2 million years ago.

Archelon
Photo: vi:User:Tran Trong Nhan chụp từ sách cũ, Public domain
Archelon
Photo: Creator: Dmitry Bogdanov, CC BY 3.0
Archelon
Photo: Nobu Tamura (http://spinops.blogspot.com), CC BY 2.5

Taxonomy

KingdomAnimalia
PhylumChordata
ClassReptilia
OrderTestudines
FamilyProtostegidae
GenusArchelon
SpeciesArchelon ischyros

Where its fossils were found

South Dakota and North Dakota, USA (Pierre Shale).

Fun facts

  • Unlike most sea turtles, Archelon had a leathery carapace instead of a hard shell.
  • The biggest known Archelon, nicknamed Brigitta, measured about 4.0 m from flipper to flipper.
  • Archelon had a hooked beak like those of birds of prey, and its jaw probably moved in a hammering motion.
  • Its tail was probably so flexible that it could bend sideways at nearly a right angle.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).