Apatosaurus
A large, long-necked sauropod with a whip-like tail.
Known for its long neck, whip-like tail, and robust build, Apatosaurus is one of the most iconic dinosaurs, though its skull was long misidentified and mounted with that of Camarasaurus until the 1970s.
- average_length
- 21–23 m (69–75 ft)
- average_mass
- 16.4–22.4 t (16.1–22.0 long tons; 18.1–24.7 short tons)
- maximum_mass
- approximately 33 t (32 long tons; 36 short tons)
- diet
- herbivorous
- family
- Diplodocidae
Lore & Background
Fossils have been found in the Morrison Formation of modern-day Colorado, Oklahoma, New Mexico, Wyoming, and Utah.
Reader's Guide
Apatosaurus is a member of the diplodocid family, differing from Diplodocus in its more robust cervical vertebrae and leg bones. Its neck vertebrae are less elongated and more heavily constructed, and its leg bones are stockier, implying a more robust animal. The tail was held above the ground during normal locomotion and may have been used as a whip to create loud noises or as a sensory organ. Apatosaurus had a single claw on each forelimb and three on each hindlimb. The genus is considered one of the more basal diplodocids, with only Amphicoelias and possibly a new, unnamed genus more primitive. Apatosaurus lived alongside Allosaurus, Camarasaurus, Diplodocus, and Stegosaurus.
Did You Know?
- Apatosaurus means 'deceptive lizard'.
- Apatosaurus had air sacs that made its vertebrae internally full of holes to lighten the skeleton.
- Some specimens of A. ajax may have reached lengths of 30 m (98 ft) and masses of 33 t (36 short tons).
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