# Iguanodon bernissartensis

> A large plant-eating ornithopod from the Early Cretaceous of Europe with a conical thumb spike. About thirty skeletons were found 322 m underground in a Belgian coal mine at Bernissart in 1878.

- Classification: Dinosauria (clade) > Ornithischia (clade) > Ornithopoda (clade) > Iguanodontia (clade) > Iguanodontidae (family) > Iguanodon (genus) > Iguanodon bernissartensis (species)
- Length: 6.3–10 m
- Hip height: 2.2–2.8 m
- Mass: 4.5 t
- Age: 125.8–119.6 million years ago (Early Cretaceous)
- Fossils found in: Sainte-Barbe Clays Formation (Hainaut); Belgium
- Diet: herbivore
- Described: George A. Boulenger, 1881
- In films: Jurassic World Dominion (2022)

Canonical page: https://dinodex.club/dinosaurs/iguanodon-bernissartensis
Last updated: 2026-09-27

## Overview

Iguanodon was the second dinosaur ever named. Gideon Mantell named it in 1825 from teeth found in Sussex that resembled those of an iguana, and he placed a spike on its nose. Only the complete skeletons from Belgium showed that the spike belonged on the thumb.

In 1878 miners at Bernissart, Belgium, found dinosaur bones 322 m underground in a coal mine. Some thirty fairly complete skeletons were recovered, most of them Iguanodon bernissartensis, named by George Boulenger in 1881. From 1882 Louis Dollo and Louis De Pauw mounted them in Brussels, where they are still displayed.

Iguanodon was a heavy animal that could walk on four legs or two. Its hand combined a spike-like thumb, three middle fingers that could bear weight and a grasping fifth finger. It lived in the Barremian to early Aptian, and I. bernissartensis is now the type species of the genus.

## Name meaning

"Iguana tooth", from iguana and Greek odous ("tooth") (Mantell 1825); bernissartensis for Bernissart, Belgium (Boulenger 1881).

## Sources

1. (2026). Paleobiology Database: Iguanodon occurrences. The Paleobiology Database (paleobiodb.org), data service 1.2, accessed 2026-09-23. https://paleobiodb.org/data1.2/occs/list.txt?base_name=Iguanodon&show=coords,paleoloc,strat,loc,ref&pgm=gplates
2. (2026). Wikipedia: Iguanodon. Wikipedia (English), accessed 2026-09-23. https://en.wikipedia.org/wiki/Iguanodon
3. Boulenger, G. A. (1881). Sur l'arc pelvien chez les dinosauriens de Bernissart. Bulletins de l'Académie royale de Belgique, 3e série, 1(5): 1-11.
4. Charig, A. J. & Chapman, S. D. (1998). Iguanodon Mantell, 1825 (Reptilia, Ornithischia): proposed designation of Iguanodon bernissartensis Boulenger in Beneden, 1881 as the type species, and proposed designation of a lectotype. Bulletin of Zoological Nomenclature 55: 99-104. https://doi.org/10.5962/bhl.part.157
5. Mantell, G. (1825). Notice on the Iguanodon, a newly discovered fossil reptile, from the sandstone of Tilgate forest, in Sussex. Philosophical Transactions of the Royal Society of London: 179-186. https://doi.org/10.1098/rstl.1825.0010
6. Natural History Museum, London (2026). Iguanodon: the teeth that led to a dinosaur discovery. nhm.ac.uk. https://www.nhm.ac.uk/discover/the-discovery-of-iguanodon.html
7. Paul, G. S. (2016). The Princeton Field Guide to Dinosaurs (2nd edition). Princeton University Press.
8. Royal Belgian Institute of Natural Sciences (2026). The Bernissart Iguanodons at a glance. naturalsciences.be. https://www.naturalsciences.be/en/discover-join/discover/the-bernissart-iguanodons-at-a-glance

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Cite as: "Iguanodon bernissartensis". DinoDex. https://dinodex.club/dinosaurs/iguanodon-bernissartensis (updated 2026-09-27).