Archelon

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Archelon
Temporal range: Late Cretaceous, 80.5Ma
Big fossil turtle.jpg
Mounted cast
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines (=Chelonii)
Suborder: Cryptodira
Family: Protostegidae
Genus: Archelon
Wieland, 1896
Type species
Archelon ischyros
Wieland, 1896
ARCHELON is also a sea-turtle conservation society, see ARCHELON, the Sea Turtle Protection Society of Greece

Archelon (from Greek αρχελών meaning ruler turtle) is a genus of extinct sea turtles, the largest that have ever been documented.

Discovery[edit]

Type specimen (YPM 3000) of Archelon ischyros in the Yale Peabody Museum, Yale University

The first specimen of Archelon (YPM 3000) was collected from the Campanian-age Pierre Shale of South Dakota (a geological formation dated to 80.5 million years ago[1])by Dr. G.R. Wieland in 1895 and described by him the following year (Wieland, 1896). The largest Archelon fossil, found in the Pierre Shale of South Dakota in the 1970s, measures more than 4 metres (13 ft) long, and about 4.9 metres (16 ft) wide from flipper to flipper. It was a marine turtle, whose closest living relative in the present day is the leatherback sea turtle.[2][3] Archelon lived at a time when a shallow sea covered most of central North America. Most of the known remains have been found in South Dakota and Wyoming. Though anatomically similar to the earlier species Protostega gigas, it was much larger.[4]

Biology[edit]

Restoration

Unlike most modern turtles, Archelon did not have a solid shell, but instead had a skeletal framework supporting a leathery or bony carapace. Other distinguishing features include a pointed tail, a narrow skull, a relatively narrow, high-vaulted shell, and a pronounced overbite.[2] The live weight of an Archelon ischyros is estimated at more than 2200 kg (4,850 lb). They probably had a very strong bite, and were optimized for feeding on pelagic mollusks such as squid.[5] The specimen exhibited by the Museum of Natural History in Vienna is estimated to have lived to be a century old, and may have died while brumating on the ocean floor.[5]

References[edit]

  1. ^ Carpenter, K. (2003). "Vertebrate Biostratigraphy of the Smoky Hill Chalk (Niobrara Formation) and the Sharon Springs Member (Pierre Shale)." High-Resolution Approaches in Stratigraphic Paleontology, 21: 421-437. doi:10.1007/978-1-4020-9053-0
  2. ^ a b http://www.uhaul.com/supergraphics/turtle/archelon.html
  3. ^ "Archelon". BBC - Science & Nature. Retrieved 2009-05-25. 
  4. ^ Marine Turtles
  5. ^ a b BHI/Fossils & Minerals/Rept. and Amph./Archelon

Published References:

  • Hay, O. P. 1908. The fossil turtles of North America. Carnegie Institution of Washington, Publication No. 75, 568 pp, 113 pl.
  • Wieland, G. R. 1896. Archelon ischyros: a new gigantic cryptodire testudinate from the Fort Pierre Cretaceous of South Dakota. American Journal of Science, 4th Series 2(12):399-412, pl. v.
  • Wieland, G. R. 1902. Notes on the Cretaceous turtles, Toxochelys and Archelon, with a classification of the marine Testudinata. American Journal of Science, Series 4, 14:95-108, 2 text-figs.
  • Wieland, G. R. 1906. The osteology of Protostega, Memoirs of the Carnegie Museum, 2(7):279-305.
  • Wieland, G. R. 1909. Revision of the Protostegidae. American Journal of Science, Series 4. 27(158):101-130, pls. ii-iv, 12 text-figs.

Online References:

External links[edit]