Dinosaurs A to Z
Rebbachisauridae

Maraapunisaurus

"huge"

Generic sauropod body-plan outline
You 1.8 m (5.9 ft) tall
Maraapunisaurus 58 m (190 ft) long
as long as 34 people standing fingertip to fingertip
generic sauropod body plan, scaled to length — not a silhouette of Maraapunisaurus
Length
58 m (190 ft)
Period
Late Jurassic (150 Mya)
Place
North America · Colorado, USA
Food
Herbivore
Clade
Rebbachisauridae

Maraapunisaurus is a genus of sauropod dinosaur from the Late Jurassic Morrison Formation of western North America. It contains one species, Maraapunisaurus fragillimus, which was originally named Amphicoelias fragillimus. It has sometimes been estimated to be the largest dinosaur specimen ever discovered. Based on surviving descriptions of a single fossil bone, scientists have produced numerous size estimates over the years; the largest estimate M. fragillimus to have been the longest known animal at 58 m in length with a mass of 150 tonne. However, because the only fossil remains were lost at some point after being studied and described in the 1870s, evidence survived only in contemporary drawings and field notes.

More recent studies have made a number of suggestions regarding the possibility of such an animal.

What we know

  • Named by (Cope, 1878).
  • Body length estimated at about 58 m.
  • Fossils found in North America and Colorado, USA.

What we guess

The reconstruction notes for Maraapunisaurus — soft tissue, color, behavior — haven't been written up yet. Only the recorded basics above are filled in so far.