Prehistoric Earth Wiki


Deinosuchus is a giant relative of the alligator that lived in the Late Cretaceous of North America.


Despite its huge size, Deinosuchus was not very different from today's crocodilians. Its teeth were very robust, and the animal's bite force is believed to have equalled or surpassed 18,000 newtons (larger than the bite force of Tyrannosaurus)[1]. Deinosuchus had a bony palate which could allow it to breathe when most of its body was underwater, and it large, heavy, deeply pitted scutes.


Deinosuchus (yellow) compared to other prehistoric crocodiles and a saltwater crocodile (green)

Because most Deinosuchus fossils are very fragmentary, size estimates vary widely. It was originally believed that it could reach lengths of 15 meters.[2] In 1999, the estimate was reduced to 8 or 10 meters.[3] Later, David Schwimmer compared various skull sizes and concluded that two groups of Deinosuchus existed: a group that lived in the eastern half of the continent and reached 8 meters, and a group that lived in the western half and grew from 10 to 12 meters.[4] These groups comprise two different species in the genus (see Classification, below).

Whatever the correct size, it was still far larger than any modern crocodilian.


At first, Deinosuchus was believed to be a giant crocodile, but later analysis showed that it was in fact more closely related to alligators.[5] There are two species, D. rugosus and D. riograndensis.[6]


Deinosuchus hunting Parasaurolophus

Deinosuchus teeth were first found in North Carolina in 1858, although they were believed to come from a genus of pliosaur.[7]

More fossils were found by John Bell Hatcher in Montana in 1903, and they were described in 1909. In 1940, a more complete Deinosuchus was found in Texas. Since then its remains have periodically turned up in seven other states such as Georgia and New Jersey, and a possible specimen has been found in Mexico.[8]



Deinosuchus lived on both sides of the Western Interior Seaway, and apparently preferred estuarine environments.[9]


It was speculated as early as 1954 that Deinosuchus may have preyed upon dinosaurs.[10] Hadrosaurid tail vertebrae discovered in 2002 seem to show tooth marks matching that of Deinosuchus, strongly supporting this theory.[11]


  1. Erickson, Gregory M.; Lappin, A. Kristopher; Vliet, Kent A. (2003). "The ontogeny of bite-force performance in American alligator (Alligator mississippiensis)" (pdf). Journal of Zoology 260 (3): 317–327. doi:10.1017/S0952836903003819. Retrieved 2009-11-02.
  2. Colbert, Edwin H; Bird, Roland T. (1954). "A gigantic crocodile from the Upper Cretaceous beds of Texas" (pdf). American Museum Novitates (American Museum of Natural History) 1688: 1–22. Retrieved 2009-02-22.
  3. Erickson, Gregory M.; Brochu, Christopher A. (March 1999). "How the 'terror crocodile' grew so big". Nature (Nature Publishing Group) 398 (6724): 205–206. doi:10.1038/18343.
  4. Schwimmer, David R. (2002). "The Size of Deinosuchus". King of the Crocodylians: The Paleobiology of Deinosuchus. Indiana University Press. pp. 42–63. ISBN 0-253-34087-X.
  5. Brochu, Christopher A. (June 14, 1999). "Phylogenetics, Taxonomy, and Historical Biogeography of Alligatoroidea". Society of Vertebrate Paleontology Memoir 6: 9–100. doi:10.2307/3889340. JSTOR 3889340.
  6. Schwimmer, D.R. (2010). "One or two species of the giant crocodylian Deinosuchus". Journal of Vertebrate Paleontology 30 (Supplement 2): 1A. doi:10.1080/02724634.2010.10411819.
  7. Emmons, Ebenezer (1858). Report of the North Carolina Geological Survey. Henry D. Turner. pp. 219–22. ISBN 1-4366-0488-5.
  8. Westgate, James; Brown, R.; Pittman, Jeffrey; Cope, Dana; Calb, Jon (2006). "First occurrences of Deinosuchus in Mexico". Journal of Vertebrate Paleontology 26 (Supplement to 3): 138A.
  9. Anglen, John J.; Lehman, Thomas M. (2000). "Habitat of the giant crocodilian Deinosuchus, Aguja Formation (Upper Cretaceous), Big Bend National Park, Texas". Journal of Vertebrate Paleontology 20 (Supplement to 3): 26A.
  10. Colbert, Edwin H. (1961). Dinosaurs: Their Discovery and Their World. E. P. Dutton. p. 243.
  11. Schwimmer, David R. (2002). "The Prey of Giants". King of the Crocodylians: The Paleobiology of Deinosuchus. Indiana University Press. pp. 167–192. ISBN 0-253-34087-X.