''Eotrachodon orientalis'' (meaning "dawn ''

Trachodon ''Trachodon'' (meaning "rough tooth") is a dubious genus of hadrosaurid dinosaur based on teeth from the Campanian-age Upper Cretaceous Judith River Formation of Montana, U.S.Leidy, J. (1856). "Notice of remains of extinct reptiles and fishes, ...

'' from the east") is a species of

hadrosaurid Hadrosaurids (), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which incl ...

that was described in 2016. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

was found in the

Mooreville Chalk Formation The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of ...

(Upper

Santonian The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya (million years ago) and 83.6 ± 0.7 mya. ...

) in

Alabama (We dare defend our rights) , anthem = " Alabama" , image_map = Alabama in United States.svg , seat = Montgomery , LargestCity = Huntsville , LargestCounty = Baldwin County , LargestMetro = Greater Birmingham , area_total_km2 = 135,7 ...

in 2007 and includes a well-preserved skull and partial skeleton, making it a rare find among dinosaurs of

Appalachia Appalachia () is a cultural region in the Eastern United States that stretches from the Southern Tier of New York State to northern Alabama and Georgia. While the Appalachian Mountains stretch from Belle Isle in Newfoundland and Labrador, ...

. Another primitive hadrosaur, ''

Lophorhothon ''Lophorhothon'' is a genus of hadrosauroid dinosaur from the Late Cretaceous, the first genus of dinosaur discovered in Alabama, in the United States. Discovery and naming Remains of this small, poorly known perhaps saurolophine dinosaur w ...

'', is also known from the same formation, although ''Eotrachodon'' lived a few million years prior. A phylogenetic study has found ''Eotrachodon'' to be the sister taxon to the hadrosaurid subfamilies

Lambeosaurinae Lambeosaurinae is a group of crested hadrosaurid dinosaurs. Classification Lambeosaurines have been traditionally split into the tribes or clades Parasaurolophini (''Parasaurolophus'', '' Charonosaurus'', others (?).) and Lambeosaurini (''Cor ...

and

Saurolophinae Saurolophinae is a subfamily of hadrosaurid dinosaurs. It has since the mid-20th century generally been called the Hadrosaurinae, a group of largely non-crested hadrosaurs related to the crested sub-family Lambeosaurinae. However, the name Hadro ...

. This, along with the other Appalachian hadrosaur ''

Hadrosaurus ''Hadrosaurus'' (; ) is a genus of hadrosaurid ornithopod dinosaurs that lived in North America during the Late Cretaceous Period in what is now the Woodbury Formation about 80 million to 78 million years ago. The holotype specimen was found in f ...

'' and possibly ''

'', '' Claosaurus'' and

both Both may refer to: Common English word * ''both'', a determiner or indefinite pronoun denoting two of something * ''both... and'', a correlative conjunction People * Both (surname) Music * The Both, an American musical duo consisting of ...

species of '' Hypsibema'', suggests that Appalachia was the ancestral area of

Hadrosauridae Hadrosaurids (), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which incl ...

See also

References

Further reading