Thespesius
| Thespesius Temporal range: Late Cretaceous,  | |
|---|---|
| The syntype fossils | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Clade: | Dinosauria | 
| Clade: | †Ornithischia | 
| Clade: | †Ornithopoda | 
| Family: | †Hadrosauridae | 
| Subfamily: | †Saurolophinae | 
| Genus: | †Thespesius Leidy, 1856 | 
| Species: | †T. occidentalis | 
| Binomial name | |
| †Thespesius occidentalis Leidy, 1856 | |
| Synonyms | |
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Thespesius (meaning "wondrous one") is a dubious genus of hadrosaurid dinosaur from the late Maastrichtian-age Upper Cretaceous Lance Formation of South Dakota.