| Lophorhothon, Eolambia, Saurolophinae, Alcovasaurus, Acristavus|
Eotrachodon orientalis is a species of hadrosaurid that was described in 2016. The holotype was found in the Mooreville Chalk Formation (Upper Santonian) in Alabama in 2007, sharing the same habitat with Lophorhothon which was another primitive hadrosaur known from skull fragments, with an exceptionally well-preserved skull, making it a rare find among dinosaurs of Appalachia, though Eotrachodon did live a few million years before Lophorhothon. A phylogenetic study has found Eotrachodon to be the sister taxon to the hadrosaurid subfamilies Lambeosaurinae and Saurolophinae. This along with the other Appalachian hadrosaur Hadrosaurus and possibly Lophorhothon, Claosaurus and both species of Hypsibema, suggests that Appalachia was the ancestral area of Hadrosauridae.