Timeline of hadrosaur researchThis timeline of hadrosaur research is a chronological listing of events in the history of paleontology focused on the hadrosauroids, a group of herbivorous ornithopod dinosaurs popularly known as the duck-billed dinosaurs. Scientific research on hadrosaurs began in the , when Joseph Leidy described the genera Thespesius and Trachodon based on scrappy fossils discovered in the western United States. Just two years later he published a description of the much better-preserved remains of an animal from New Jersey that he named Hadrosaurus.
ProsaurolophusProsaurolophus (ˌproʊsɔːˈrɒləfəs; meaning "before Saurolophus", in comparison to the later dinosaur with a similar head crest) is a genus of hadrosaurid (or duck-billed) dinosaur from the Late Cretaceous of North America. It is known from the remains of at least 25 individuals belonging to two species, including skulls and skeletons, but it remains obscure. Its fossils have been found in the late Campanian-age Upper Cretaceous Dinosaur Park Formation in Alberta, and the roughly contemporaneous Two Medicine Formation in Montana, dating to around 75.
KritosauriniKritosaurini is a tribe of saurolophine hadrosaurid dinosaurs from the Late Cretaceous. The first member of the group discovered and named was Kritosaurus; it was named by paleontologist Barnum Brown in 1910. Four years later, Canadian paleontologist Lawrence Lambe would name Gryposaurus. The similarity between the two taxa was immediately recognized, and throughout the twentieth century the validity of the latter genus was doubted, with it being suggested both species were the same.
MaiasauraMaiasaura (from the Greek μαῖα, meaning "good mother" and σαύρα, the feminine form of saurus, meaning "reptile") is a large herbivorous saurolophine hadrosaurid ("duck-billed") dinosaur genus that lived in the area currently covered by the state of Montana and the province of Alberta, Canada, in the Upper Cretaceous Period (mid to late Campanian), about 76.7 million years ago. The first remains of Maiasaura were discovered in 1978 by Bynum, Montana resident Laurie Trexler. The genus was named in 1979.
KritosaurusKritosaurus is an incompletely known genus of hadrosaurid (duck-billed) dinosaur. It lived about 74.5-66 million years ago, in the Late Cretaceous of North America. The name means "separated lizard" (referring to the arrangement of the cheek bones in an incomplete type skull), but is often mistranslated as "noble lizard" in reference to the presumed "Roman nose" (in the original specimen, the nasal region was fragmented and disarticulated, and was originally restored flat).
EdmontosaurusEdmontosaurus (ɛdˌmɒntəˈsɔːrəs ) (meaning "lizard from Edmonton"), often colloquially and historically known as Anatosaurus (meaning "duck lizard"), is a genus of hadrosaurid (duck-billed) dinosaur It contains two known species: Edmontosaurus regalis and Edmontosaurus annectens. Fossils of E. regalis have been found in rocks of western North America that date from the late Campanian age of the Cretaceous period 73 million years ago, while those of E.