# Acrocanthosaurus atokensis

> A large carcharodontosaurid predator from the Early Cretaceous of North America, with a ridge of very tall spines along its neck and back. Its best skeleton, "Fran", was found in Oklahoma and is in North Carolina.

- Classification: Dinosauria (clade) > Saurischia (clade) > Theropoda (clade) > Tetanurae (clade) > Allosauroidea (superfamily) > Carcharodontosauridae (family) > Acrocanthosaurus (genus) > Acrocanthosaurus atokensis (species)
- Length: 11–12 m
- Hip height: 2.8–3.2 m
- Mass: 4.4–8.4 t
- Age: 121.4–113.2 million years ago (Early Cretaceous)
- Fossils found in: Antlers Formation (Oklahoma); United States
- Diet: carnivore
- Described: J. Willis Stovall & Wann Langston Jr., 1950

Canonical page: https://dinodex.club/dinosaurs/acrocanthosaurus-atokensis
Last updated: 2026-09-27

## Overview

Acrocanthosaurus atokensis lived in North America in the Early Cretaceous (Aptian-Albian). J. Willis Stovall and Wann Langston Jr. named it in 1950 from two partial skeletons found in the Antlers Formation of Atoka County, Oklahoma (OMNH 10146 and 10147).

Its name, "high-spined lizard", refers to the very tall spines on its neck and back vertebrae, which probably supported a thick muscular ridge rather than a thin sail. A nearly complete skull (NCSM 14345, "Fran") was found near Idabel, Oklahoma, and is displayed at the North Carolina Museum of Natural Sciences.

It was one of the largest predators of its time, around 11 to 12 m long. Eddy and Clarke (2011) restudied the skull and placed it within the Carcharodontosauridae, the family of Giganotosaurus and Carcharodontosaurus. Large theropod trackways in the Glen Rose Formation of Texas are often attributed to it.

## Name meaning

"High-spined lizard", from Greek akra ("high"), akantha ("spine") and sauros ("lizard"); atokensis for Atoka County, Oklahoma (Stovall & Langston 1950).

## Sources

1. (2026). Paleobiology Database: Acrocanthosaurus occurrences. The Paleobiology Database (paleobiodb.org), data service 1.2, accessed 2026-09-23. https://paleobiodb.org/data1.2/occs/list.txt?base_name=Acrocanthosaurus&show=coords,paleoloc,strat,loc,ref&pgm=gplates
2. (2026). Wikipedia: Acrocanthosaurus. Wikipedia (English), accessed 2026-09-23. https://en.wikipedia.org/wiki/Acrocanthosaurus
3. Eddy, D. R. & Clarke, J. A. (2011). New information on the cranial anatomy of Acrocanthosaurus atokensis and its implications for the phylogeny of Allosauroidea (Dinosauria: Theropoda). PLoS ONE 6: e17932. https://doi.org/10.1371/journal.pone.0017932
4. Paul, G. S. (2016). The Princeton Field Guide to Dinosaurs (2nd edition). Princeton University Press.
5. Stovall, J. W. & Langston, W., Jr. (1950). Acrocanthosaurus atokensis, a new genus and species of Lower Cretaceous Theropoda from Oklahoma. American Midland Naturalist 43: 696. https://doi.org/10.2307/2421859

---

Cite as: "Acrocanthosaurus atokensis". DinoDex. https://dinodex.club/dinosaurs/acrocanthosaurus-atokensis (updated 2026-09-27).