Atlantosaurus Facts
| Diet | Herbivore |
| Height | 4m |
| Length | 20m |
| Weight | 15 tonnes |
| Environment | Land |
| Era | Jurassic |
| Period | Late Jurassic |
| Type | Sauropod |
| Location | North America |

| Diet | Herbivore |
| Height | 4m |
| Length | 20m |
| Weight | 15 tonnes |
| Environment | Land |
| Era | Jurassic |
| Period | Late Jurassic |
| Type | Sauropod |
| Location | North America |
Atlantosaurus was a large sauropod dinosaur that lived during the Late Jurassic period, approximately 157 to 145 million years ago. It holds the distinction of being the first sauropod ever formally described, making it a historically significant discovery in palaeontology. However, this early description came at a cost, as it was found during the infamous Bone Wars of the 19th century, when scientific rigour often took second place to the race for academic fame.
This massive herbivore would have roamed the ancient landscapes of what is now Colorado, USA. Like other sauropods, Atlantosaurus possessed the characteristic long neck and tail, along with a relatively small head and columnar legs to support its enormous bulk. Estimates suggest it reached lengths of around 20 metres and stood approximately 4 metres tall at the hip, weighing roughly 15 tonnes.
As a plant-eater, Atlantosaurus would have used its long neck to reach vegetation at various heights, from ground-level ferns to tall conifer trees. Its teeth were designed for stripping leaves rather than chewing, so it likely swallowed stones to help grind plant material in its stomach.
Unfortunately, the original fossil remains of Atlantosaurus are quite fragmentary, consisting mainly of vertebrae and limb bones. This has led many palaeontologists to consider it a dubious genus, as there isn't enough material to definitively distinguish it from other known sauropods of the same time period.
Due to the fragmentary nature of the fossils, no distinctive features can be confidently attributed to Atlantosaurus. The remains suggest a typical large sauropod with a long neck, long tail, and massive body supported by pillar-like legs.
Atlantosaurus likely lived in herds, as evidenced by sauropod trackways from the same period. It would have spent most of its time feeding, using its long neck to browse vegetation at different levels without moving its massive body frequently.
Atlantosaurus was first described by Othniel Charles Marsh in 1877. The original fossils were discovered at Morrison Formation, Colorado, USA.