Seismosaurus
Order: Saurischia · Suborder: Sauropodomorpha · Infraorder: Sauropoda · Family: Diplodocidae
Found in New Mexico, Seismosaurus may prove to be the longest dinosaur known. While Argentinasaurus was probably taller and heavier, Seismosaurus was as long as half a football field. In the absence of good limb bone fossils, some scientists think that its legs were short, giving rise to its description as the "dachshund" of giant dinosaurs. Like other sauropods, Seismosaurus probably used gastroliths to grind its food after swallowing it.
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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 Seismosaurus mean?
The name Seismosaurus means “Earth-Shaking Lizard”. It is pronounced size-muh-SAWR-us.
When did Seismosaurus live?
Seismosaurus lived during the Late Jurassic.
Was Seismosaurus a carnivore or a herbivore?
Seismosaurus was a herbivore.
How big was Seismosaurus?
Seismosaurus was about 150 feet (45.7 meters) long, around 84 feet (25.6 meters) tall, weighing up to 200,000 pounds (90,720 kg).
Related dinosaurs
Other dinosaurs from the Diplodocidae family.
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