Haplocanthosaurus
Order: Saurischia · Suborder: Sauropodomorpha · Infraorder: Sauropoda · Family: Cetiosauridae
Haplocanthosaurus is the most primitive sauropod yet discovered in North America and the only known representative of the basal sauropods of the group Cetiosauridae. Found in Colorado, Wyoming and Utah, this giant, four-legged browsingdinosaur had solid, single-spined vertebrae, and a short neck and tail. Although known for nearly a century, recent finds have established it as a far larger animal than first thought.
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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 Haplocanthosaurus mean?
The name Haplocanthosaurus means “Single-Spined Lizard”. It is pronounced hap-low-KANTH-uh-SAWR-uss.
When did Haplocanthosaurus live?
Haplocanthosaurus lived during the Late Jurassic.
Was Haplocanthosaurus a carnivore or a herbivore?
Haplocanthosaurus was a herbivore.
How big was Haplocanthosaurus?
Haplocanthosaurus was about 72 feet (21.9 meters) long, around 35 feet (10.7 meters) tall, weighing up to 45,000 pounds (20,412 kg).
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