Claosaurus is a genus of hadrosauroid dinosaur that lived during the Late Cretaceous Period (Santonian-Campanian).
Dryptosaurus is a genus of basal eotyrannosaurian theropod dinosaur that lived on the island continent of Appalachia approximately 67 million years ago during the end of the Maastrichtian age of the Late Cretaceous period. Dryptosaurus was a large, bipedal, ground-dwelling carnivore that could grow up to 7.5 metres (25 ft) long and weigh up to 1.5 metric tons. Although it is now largely unknown outside of academic circles, the famous 1897 painting of the genus by Charles R. Knight made Dryptosaurus one of the more widely known dinosaurs of its time, in spite of its poor fossil record. First described by Edward Drinker Cope in 1866 and later renamed by Othniel Charles Marsh in 1877, Dryptosaurus is among the very first theropod dinosaurs ever known to science.
Anoplosaurus is an extinct genus of herbivorous nodosaurid dinosaur, from the late Albian-age Lower Cretaceous Cambridge Greensand of Cambridgeshire, England. It has in the past been classified with either the armored dinosaurs or the ornithopods, but current thought has been in agreement with the "armored dinosaur" interpretation, placing it in the Ankylosauria.
Barsboldia is a genus of large hadrosaurid dinosaur from the early Maastrichtian Nemegt Formation of Ömnogöv', Mongolia. It is known from a partial vertebral column, partial pelvis, and some ribs.
Calamosaurus was a genus of small theropod dinosaur from the Barremian-age Lower Cretaceous Wessex Formation of the Isle of Wight, England. It is based on two cervical vertebrae, collected by Reverend William Fox.
Texasetes is a genus of ankylosaurian dinosaurs from the late Lower Cretaceous of North America. This poorly known genus has been recovered from the Paw Paw Formation near Haslet, Tarrant County, Texas, which has also produced the nodosaurid ankylosaur Pawpawsaurus.
Claorhynchus is a dubious genus of cerapodan dinosaur with a confusing history behind it. It has been considered to be both a hadrosaurid and a ceratopsid, sometimes the same as Triceratops, with two different assignments as to discovery formation and location, and what bones make up its type remains.
"Coelosaurus" antiquus is a dubious species of theropod dinosaurs. It was named by Joseph Leidy in 1865 for two tibiae found in the Navesink Formation of New Jersey.
Hoplitosaurus was a genus of armored dinosaur related to Polacanthus. It was named from a partial skeleton found in the ?Barremian-age Lower Cretaceous Lakota Formation of Custer County, South Dakota. It is an obscure genus which has been subject to some misinterpretation of its damaged remains. Although there was a push to synonymize it with Polacanthus in the late 1980s-early 1990s, Hoplitosaurus has been accepted as a valid albeit poorly known genus in more recent reviews.
Polyonax was a genus of ceratopsid dinosaur from the late Maastrichtian-age Upper Cretaceous Denver Formation of Colorado, United States. Founded upon poor remains, it is today regarded as a dubious name.
Cionodon is a dubious genus of hadrosaurid dinosaur from the Late Cretaceous. The type species, C. arctatus, was found in the Denver Formation of Lodge Pole Creek, Colorado and was formally described by Edward Drinker Cope in 1874 based on the holotype AMNH 3951, collected in 1873. It is a nomen dubium because it is based on very fragmentary remains. Two other species have since been described: Cionodon kysylkumensis, based on the holotype CCMGE 1/3760 from Uzbekistan, and Cionodon stenopsis, discovered in rocks from the Judith River Formation of Alberta, Canada in 1874. Although both are probably hadrosaurs, they are known only from fragmentary remains and Cionodon kysylkumensis has since been reclassified as Bactrosaurus kysylkumensis.
Orthomerus is a genus of dubious hadrosaurid dinosaur from the Late Cretaceous of the Netherlands. It is today an obscure genus, but in the past was conflated with the much better known Telmatosaurus.
Cedrorestes is a genus of iguanodontian dinosaur from the Early Cretaceous of Utah. It is based on an incomplete skeleton which was found in the Valanginian-age Yellow Cat Member of the Cedar Mountain Formation.
Teresa Maryańska was a Polish paleontologist who specialized in Mongolian dinosaurs, particularly pachycephalosaurians and ankylosaurians. Peter Dodson states that in 1974 Maryanska together with Halszka Osmólska were among the first "women to describe new kinds of dinosaurs". She is considered not only as one of Poland's but also one of the world's leading experts on dinosaurs.
The Merchantville Formation is a geological formation in the northeastern United States whose strata date back to the Late Cretaceous, around the time of the Santonian and Campanian age. Dinosaur remains are among the fossils that have been recovered from the formation.
The Donoho Creek Formation is a Mesozoic geologic formation in South Carolina. Dinosaur remains are among the fossils that have been recovered from the formation.
The Marshalltown Formation is a Mesozoic geologic formation. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.
The Black Creek Group is a geologic group in North Carolina. It preserves fossils dating back to the Late Cretaceous period.
Riabininohadros is an extinct genus of ankylopollexian dinosaur from the Maastrichtian of Crimea. Its type species is Riabininohadros weberi, emended to Riabininohadros weberae. It was originally classified as a species of Orthomerus, until 2015.
This 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 1850s, 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.
