Hadrodaurus, a genus of hadrosaurid ornithopod dinosaurs, thrived in North America during the Late Cretaceous period, approximately 75 to 65 million years ago.

Initially, the lack of a skull in the skeleton raised concerns about its classification, leading many scientists to consider it a nomen dubium, or dubious name, despite Hadrosaurus being the type genus of the Hadrosauridae family. However, in 2011, a re-evaluation of the fossil material identified several distinctive characteristics in the skeleton, validating the use of the genus Hadrodaurus and species H. foulkii as valid taxa.

Due to the scarcity of fossil remains, the full extent of Hadrodaurus' physical features remains largely unknown. However, preliminary findings suggest it may have been a medium-sized dinosaur, possibly measuring several meters in length. A more comprehensive understanding of its skeletal structure, anatomical traits, and other physical characteristics requires further research and the discovery of additional fossil evidence.