Acrocanthosaurus
Order: Saurischia · Suborder: Theropoda · Infraorder: Tetanurae · Family: Allosauridae (family not firmly confirmed)
Acrocanthosaurus is one of the few allosaurids known to North America, with fragmentary remains having been found in Texas and Oklahoma. Its back was marked by spines of up to 2 feet (60 cm) high in large specimens. Unlike the spines in other dinosaurs, those in Acrocanthosaurus were thickly covered with muscle, and it is unlikely that this ridge was used for cooling. (CompareSpinosaurus) It is estimated that Acrocanthosaurus could run as fast as 25 mph (40 km/h).
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Reference background: Natural History Museum, London — Dinosaurs; Smithsonian National Museum of Natural History — Dinosaurs; American Museum of Natural History — Dinosaurs & Fossils. Figures are typical published ranges; taxonomy follows the source era and modern consensus is noted where it differs. See our sources & fact-check policy.
Frequently asked questions
What does Acrocanthosaurus mean?
The name Acrocanthosaurus means “High Spine Lizard”. It is pronounced ak-ro-KANTH-uh-SAWR-us.
When did Acrocanthosaurus live?
Acrocanthosaurus lived during the Early Cretaceous.
Was Acrocanthosaurus a carnivore or a herbivore?
Acrocanthosaurus was a carnivore.
How big was Acrocanthosaurus?
Acrocanthosaurus was about 40 feet (12.2 meters) long, around 18 feet (5.5 meters) tall, weighing up to 4,000 - 6,000 lbs (1,814 - 2,722 kg).
Related dinosaurs
Other dinosaurs from the Allosauridae family.
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