Allosaurus is an extinct genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic period. The name "Allosaurus" means "different lizard", alluding to its unique concave vertebrae. It is derived from the Greek words ἄλλος and σαῦρος. The first fossil remains that could definitively be ascribed to this genus were described in 1877 by famed paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles.
Pteranodon ; from Ancient Greek πτερόν and ἀνόδων is a genus of pterosaur that included some of the largest known flying reptiles, with P. longiceps having a wingspan of over 6 m (20 ft). They lived during the late Cretaceous geological period of North America in present-day Kansas, Nebraska, Wyoming, South Dakota and Alabama. More fossil specimens of Pteranodon have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway.
Camarasaurus was a genus of quadrupedal, herbivorous dinosaurs and is the most common North American sauropod fossil. Its fossil remains have been found in the Morrison Formation, dating to the Late Jurassic epoch, between 155 and 145 million years ago.
Barosaurus was a giant, long-tailed, long-necked, plant-eating sauropod dinosaur closely related to the more familiar Diplodocus. Remains have been found in the Morrison Formation from the Upper Jurassic Period of Utah and South Dakota. It is present in stratigraphic zones 2–5.
Dryosaurus is a genus of an ornithopod dinosaur that lived in the Late Jurassic period. It was an iguanodont. Fossils have been found in the western United States and were first discovered in the late 19th century. Valdosaurus canaliculatus and Dysalotosaurus lettowvorbecki were both formerly considered to represent species of Dryosaurus.
Coelurus is a genus of coelurosaurian dinosaur from the Late Jurassic period. The name means "hollow tail", referring to its hollow tail vertebrae. Although its name is linked to one of the main divisions of theropods (Coelurosauria), it has historically been poorly understood, and sometimes confused with its better-known contemporary Ornitholestes. Like many dinosaurs studied in the early years of paleontology, it has had a confusing taxonomic history, with several species being named and later transferred to other genera or abandoned. Only one species is currently recognized as valid: the type species, C. fragilis, described by Othniel Charles Marsh in 1879. It is known from one partial skeleton found in the Morrison Formation of Wyoming, United States. It was a small bipedal carnivore with elongate legs.
Laosaurus is a genus of neornithischian dinosaur. The type species, Laosaurus celer, was first described by O.C. Marsh in 1878 from remains from the Oxfordian-Tithonian-age Upper Jurassic Morrison Formation of Wyoming. The validity of this genus is doubtful because it is based on fragmentary fossils. A second species from the Morrison Formation, L. gracilis, and a species from the late Cretaceous Allison Formation of Alberta, Canada, Laosaurus minimus, are also considered dubious.
Nanosaurus is the name given to a genus of neornithischian dinosaur that lived about 155 to 148 million years ago, during the Late Jurassic-age. Its fossils are known from the Morrison Formation of the south-western United States. The type and only species, Nanosaurus agilis, was described and named by Othniel Charles Marsh in 1877. The taxon has a complicated taxonomic history, largely the work of Marsh and Peter M. Galton, involving the genera Laosaurus, Hallopus, Drinker, Othnielia, and Othnielosaurus, the latter three now being considered to be synonyms of Nanosaurus. It had historically been classified as a hypsilophodont or fabrosaur, types of generalized small bipedal herbivore, but more recent research has abandoned these groupings as paraphyletic and Nanosaurus is today considered a basal member of Neornithischia.
Comodactylus is a genus of "rhamphorhynchoid" pterosaur from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Wyoming, United States, named for a single wing metacarpal.
Mesadactylus is an extinct genus of pterosaur from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Colorado, United States. The genus was named in 1989 by James Jensen and Kevin Padian. The type species is Mesadactylus ornithosphyos.
Laopteryx is the name assigned to a pterosaur from the Upper Jurassic Morrison Formation of Wyoming, United States; it was originally thought to be a bird.
Kepodactylus is an extinct genus of ctenochasmatid pterodactyloid pterosaur from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Colorado, United States.
Rhamphinion is a genus of pterosaurs from the Sinemurian-mid Pliensbachian-age Lower Jurassic Kayenta Formation of northeastern Arizona, United States. The type species is R. jenkinsi.
Utahdactylus was a genus of extinct reptile from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Utah, United States. Based on DM 002/CEUM 32588, Czerkas and Mickelson (2002) identified it as a "rhamphorhynchoid" pterosaur. Bennett (2007) later concluded that it has no diagnostic features of the Pterosauria, and cannot be positively identified beyond being an indeterminate diapsid. More recent work on newly prepared material, however, seems to confirm once again that Utahdactylus was a pterosaur.
Puntanipterus is a genus of pterodactyloid pterosaur from the Early Cretaceous period La Cruz Formation of San Luis, Argentina.
Rhabdopelix is a dubious genus of possible kuehneosaurid reptile, from the Late Triassic-age Lockatong Formation of Pennsylvania, United States. Based on partial, possibly chimeric remains, it was described by American naturalist and paleontologist Edward Drinker Cope as an early pterosaur. It held this status until the 1960s, when Ned Colbert reevaluated it for his description of Icarosaurus. He noted that the bones came from a block with the remains of other animals, and that Cope had misinterpreted some of the remains; for example, the rod-like "pubic bones" that had given it its name were actually much more like the bony structures used by Icarosaurus and related animals to glide. Additionally, he couldn't relocate the fossils, which are assumed to be lost. He recommended considering Rhabdopelix a dubious name. Peter Wellnhofer retained it as a pterosaur of unknown affinities in his 1978 review, but rejected this by 1991.
Camarasaurus grandis is an extinct species of sauropod dinosaur in the genus that lived during the Jurassic in what is now the western United States. It is the geologically oldest of the four species of the genus Camarasaurus.
Theretairus is a Late Jurassic genus of sphenodont reptile from the Morrison Formation of western North America, present in stratigraphic zones 5 and 6.
Eobatrachus is a dubious genus of extinct frog known only from the holotype, YPM 1862, part of the right humerus, found in Reed's Quarry 9 near Como Bluff, Wyoming in the Late Jurassic-aged Morrison Formation. The type, and only species, E. agilis, was named by Othniel Charles Marsh in 1887 and he initially interpreted it as a mammal, although it was later re-classified as a genus of frog related to Comobatrachus and Eobatrachus is now seen as a dubious amphibian genus, possibly belonging to Anura (frogs) according to Foster (2007).
Pteranodontoidea is an extinct clade of ornithocheiroid pterosaurs from the Early to Late Cretaceous of Asia, Africa, Europe, North America and South America. It was named by Alexander Wilhelm Armin Kellner in 1996. In 2003, Kellner defined the clade as a node-based taxon consisting of the last common ancestor of Anhanguera, Pteranodon and all its descendants. The clade Ornithocheiroidea is sometimes considered to be the senior synonym of Pteranodontoidea, however it depends on its definition. Brian Andres in his analyses, converts Ornithocheiroidea using the definition of Kellner (2003) to avoid this synonymy.
