Kingdom Animalia
Phylum Chordata
Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
Superorder Dinosauria
Order Saurischia
Suborder Sauropodomorpha
Superfamily Diplodocoidea
Family Diplodocidae
Subfamily Apatosaurinae
Genus Apatosaurus
1st Species Apatosaurus ajax
Other attributes
Time Range 152-151 mya
Location United States of America
Name Meaning Deceptive reptile
Physical Dimensions 22.7 meters long
Weight 19.7 tonnes
Dietary Classification Herbivore

Apatosaurus is a diplodocid sauropod sauropodomorph dinosaur from the Late Jurassic of the United States of America. It was named in 1877 by Othniel Charles Marsh. It is a somewhat popular dinosaur, and it was considered to be a senior synonym of Brontosaurus for a long time; however, many people now consider it to be a different genus due to skeletal differences.


Like its cousin, Brontosaurus, Apatosaurus was a sauropod with a bulky body, 4 large, erect, pillar-like legs (with one large claw on each hand and 3 clawed toes on each foot), an extremely long, whip-like tail, a long neck, and a small head. An interesting thing to note is that near the underside of its neck were a row of large bumps used for intraspecific combat (fighting with other members of its species). Its body would have been covered in scaly skin.


Apatosaurus was an herbivore, primarily feeding on ferns, cycads, horsetails, and leaves, but also snacking on algae from time to time. Its peg-like teeth were used to strip branches of their leaves, and its long neck would have helped it reach plants further away from its body.


Like any other sauropod discovered during the late 1800s-early 1900s, Apatosaurus was thought to be a swamp-dwelling herbivore, constantly feeding on underwater plants knee-deep in water; however, recent findings have confirmed that it spent 95% of its time on land, feeding on ground plants such as ferns, cycads, horsetails, and trees (when feeding on the latter, it would rear up and use its peg-like teeth to strip their branches of all their leaves). In order to breathe properly, such a massive sauropod like Apatosaurus had avian air sacs that lay in its neck and trunk and connected to its lungs; this would have brought in a steady supply of unused oxygen that would allow normal respiration. As well as this, Apatosaurus could hit a massive growth spurt in its life; while its true lifespan remains unknown, it is generally believed that juveniles could grow to full size in just 10 years. Both the avian respiratory system and the extreme growth spurt can serve as proof that Apatosaurus, like any other dinosaur, had a warm-blooded metabolism.

In popular cultureEdit

Back when Brontosaurus was thought to be a synonym of Apatosaurus, the latter was perhaps the most popular herbivorous dinosaur among the American public, appearing in major pieces of media like Fantasia, The Land Before Time, and Jurassic Park. However, due to the recent rebirth of Brontosaurus as a generic name, Apatosaurus may as well take a backseat to its bulkier (and slightly smaller) cousin.

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