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Iguanodon: Dinosaur Quick Facts


Iguanodon was a plant-eating dinosaur that had a conical spike on each thumb. The Iguanodon lived during the early Cretaceous period, about 135 to 125 million years ago. Iguanodon was a dinosaur that had a horny, toothless beak and tightly-packed cheek teeth. On each hand, Iguanodon had four fingers plus a conical thumb spike on each hand. These thumb spikes ranged from 2 to 6 inches long were probably used to obtain food or to defend itself against other dinosaurs. Iguanodon had a flat, stiff tail and three-toed hind feet with hoof-like claws. Its legs were much larger than its arms which allowed it to run fast and stand on its hind legs if needed.

The Iguanodon’s Name

Meaning – Iguanodon means “Iguana tooth”
Named By – Gideon Mantell
When Named – 1825

What did the Iguanodon eat?

Herbivore (plant-eater) – Iguanodon probably ate cycads, conifers, and ginkgos

How big was the Iguanodon?

Length – 20-33 ft (6-10 m) long
Height – 9 ft (2.7 m) tall at the hips
Weight – 4-5 tons

When did the Iguanodon live?

Cretaceous period, about 135-125 million years ago

Where did the Iguanodon live?

Fossils have been found in EnglandBelgium, and Germany, northern Africa, and the USA.

Where have fossils from the Iguanodon been found?

Teeth and a few bones of Iguanodon were found in 1822, in Sussex, England. Hundreds of Iguanodon fossils have been found since then.

What is the classification of the Iguanodon?

Kingdom Animalia
Phylum Chordata
Class Archosauria
Order Ornithischia
Suborder Ornithopoda
Infraorder Iguanodontia
Genus Iguanodon
Species I. bernissartensis

Interesting fact about the Iguanodon:

Iguanodon was the second dinosaur that was scientifically named. This dinosaur had a hard, conical spike on each thumb.This plated dinosaur was a plant eater. It must have eaten a large amount of low-calorie plant material each day to sustain its bulk, probably using its toothless beak to get food. There is debate on whether or not Stegosaurus could rear up on its rear legs to forage for vegetation. If it couldn’t rear up, it was limited mostly to plantsno taller than about 3 feet tall. This would have included ferns, smaller club mosses, cycads, horsetails, and bushy conifers.