Category: Dinosaur

Acrocanthosaurus (/ak-rə-kan-thə-sor-əs), high spine lizard, was the large apex predator for Early Cretaceous. It was almost as large as the later Tyrannosaurus, but is related to the Jurassic Allosaurus and African Carcharodontosaurus. It was characterized by long vertebrae that probably supported a hump (Paul, 2010).



Genera and Species

Classification: Theropoda, Tetanurae, Carnsauria, Allosauridae

Species: A. atokensis.


Acrocanthosaurus was a meat-eater with a relatively small head, with the normal allosaur eye horns developed into ridges protecting the eyes and joined to a second ridge running along the top of the nose. The lower jaw is very deep at the back end, giving Acrocanthosaurus a more powerful bite than Allosaurus, with larger teeth. In general, the body shape and limbs are characteristic of allosaurids, except for a ridge running from behind the skull to the base of the tail, and 3 hand claws shaped like scimitars and designed more for holding than puncturing. The back ridge was supported by 30 cm (1 ft) dorsal spines jutting from the vertebrae (Worth, 1999).


Length 8 - 12 m (26 - 40 ft).

Weight 2 - 4.5 tons.


The Paluxy River fossil foot prints in Texas may show a large therapod stalking a line of sauropods and part of an attack. The best guess is that the theropod was Acrocanthosaurus and the brachiosaurs were Astrodon or Pleurocoelus. The Acro seems to have followed the Astrodon, sped up, and then hopped onto the animal’s flank. The tracks show the Acrocanthosaurus dragged on one foot by the Astrodon before being shaken loose (Knol, 2005).

History of Discovery

Discovery, Stovall and Langston in 1950. The fossils consist of partial skulls and associated skeletal remains.


Found in North America (Oklahoma, Texas and Utah, USA) coastal flood plains with marsh and swamp. An Acrocanthosaurus Astrodon Zone descended from the Late Jurassic fauna contained broken forests and savannah and existed along the Gulf Coast to Maryland.


  1. Paul, G. (2010). The Princeton Field Guide to Dinosaurs (pp. 2493). Princeton, New Jersey: University Press Princeton.

  2. Worth, G. (1999). The Dinosaur Encyclopaedia (pp. 211). Scarborough, Western Australia: HyperWorks Reference Software.

  3. Knol, R. (2005, May 5). Early Cretaceous of North America. Retrieved April 3, 2014, from