| Lurdusaurus Temporal range: Early Cretaceous,
| |
|---|---|
| |
| Cast of Lurdusaurus forelimb at the Muséum des sciences naturelles de Belgique, Brussels | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | †Ornithischia |
| Clade: | †Neornithischia |
| Clade: | †Ornithopoda |
| Clade: | †Styracosterna |
| Clade: | †Hadrosauriformes |
| Genus: | †Lurdusaurus Taquet and Russell, 1999 |
| Species: | †L. arenatus
|
| Binomial name | |
| †Lurdusaurus arenatus | |
Lurdusaurus ("heavy lizard") is a genus of massive and unusually shaped iguanodont dinosaur from the Elrhaz Formation in Niger. It contains one species, L. arenatus. The formation dates to the Early Cretaceous, roughly 112 million years ago. Lurdusaurus has a highly atypical body plan for an iguanodont, with a small skull, long neck, rotund torso, and powerful forelimbs and claws, somewhat reminiscent of a ground sloth. Its metacarpals (wrist bones) are fused and reinforced into a large block, and the thumb spike is remarkably enormous. These would have allowed the hand to have functioned almost like a ball-and-chain flail. Lurdusaurus is estimated to have been 7–9 m (23–30 ft) long and 2 m (6 ft 7 in) high when on all-fours, but its stomach would have been only 70 cm (2 ft 4 in) off the ground. It may have weighed 2.5–5.5 t (2.8–6.1 short tons), conspicuously heavy for an iguanodontid this size.
Paleontologist Thomas R. Holtz Jr. speculated Lurdusaurus may have behaved much like a hippo. It lived in a forested, riverine environment alongside the iguanodonts Elrhazosaurus and Ouranosaurus, the sauropod Nigersaurus, an undescribed titanosaurid, the spinosaurid Suchomimus, the carcharodontosaurid Eocarcharia, the abelisaurid Kryptops, and an undescribed noasaurid. The site also yielded several crocodylomorph species and a pterosaur.