| Uronautes Temporal range: Late Cretaceous | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Superorder: | † Sauropterygia |
| Order: | † Plesiosauria |
| Family: | † Rhomaleosauridae |
| Genus: | † Uronautes Cope, 1877 |
| Species | |
Uronautes is a dubious genus of extinct plesiosaur from the family Rhomaleosauridae. Uronautes is known from several fossilized vertebra, portions of a few limbs, and ribs. [1]
The word Uronautes comes from a fusion of the two Greek words Ουρα, meaning "tailed," and Ναυτεσ, meaning "sailor", or "mariner". [2] The species name of U. cetiformis comes from the Greek word for whale (or any large sea monster), κῆτος and the Latin word forma, which means "shaped", of "formed" meaning "shape". [3]
Uronautes was first described by the American paleontologist, Edward Drinker Cope in 1876. [4] Because of the small number of supposed Uronautes fossils, Samuel Paul Welles described the genus as a "nomen dubium", doubting that the remains were evidence of a true genus in 1956. [5] The genus Uronautes is still considered a nomen dubium which means "dubious name". In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application.
Like many other rhomaleosaurids, such as Rhomaleosaurus , Uronautes was a short-necked plesiosaur. The Cervical vertebrae are short, with partially attached processes and double-headed ribs. [6]
Supposed Urounautes fossils are known from only a few locations: the Cretaceous deposits of the Fox Hills, and in similar deposits near Fort Pierre, and the Judith River, all in Montana. [8] [9]
Trachodon is a dubious genus of hadrosaurid dinosaur based on teeth from the Campanian-age Upper Cretaceous Judith River Formation of Montana, U.S. It is a historically important genus with a convoluted taxonomy that has been all but abandoned by modern dinosaur paleontologists.
Elasmosaurus (;) is a genus of plesiosaur that lived in North America during the Campanian stage of the Late Cretaceous period, about 80.5 million years ago. The first specimen was discovered in 1867 near Fort Wallace, Kansas, US, and was sent to the American paleontologist Edward Drinker Cope, who named it E. platyurus in 1868. The generic name means "thin-plate reptile", and the specific name means "flat-tailed". Cope originally reconstructed the skeleton of Elasmosaurus with the skull at the end of the tail, an error which was made light of by the paleontologist Othniel Charles Marsh, and became part of their "Bone Wars" rivalry. Only one incomplete Elasmosaurus skeleton is definitely known, consisting of a fragmentary skull, the spine, and the pectoral and pelvic girdles, and a single species is recognized today; other species are now considered invalid or have been moved to other genera.
The Plesiosauria or Plesiosaurs are an order or clade of extinct Mesozoic marine reptiles, belonging to the Sauropterygia.
Champsosaurus is an extinct genus of crocodile-like choristodere reptile, known from the Late Cretaceous and early Paleogene periods of North America and Europe (Campanian-Paleocene). The name Champsosaurus is thought to come from champsai, (χαμψαι) said in an Ancient Greek source to be an Egyptian word for "crocodiles", and sauros, (σαύρος) Greek for "lizard". The morphology of Champsosaurus resembles that of gharials, with a long, elongated snout. It was native to freshwater environments where it likely preyed on fish, similar to living gharials.
Aublysodon is a genus of carnivorous dinosaurs known only from the Judith River Formation in Montana, which has been dated to the late Campanian age of the late Cretaceous period. The only currently recognized species, Aublysodon mirandus, was named by paleontologist Joseph Leidy in 1868. It is now considered dubious, because the type specimen consists only of an isolated premaxillary (front) tooth. Although this specimen is now lost, similar teeth have been found in many US states, western Canada, and Asia. These teeth almost certainly belong to juvenile tyrannosaurine tyrannosaurids, but most have not been identified to species level. However, it is likely that the type tooth belongs to one of the species in the genus Daspletosaurus, which was present in contemporary formations, and which matches specific details of the original tooth. The synapomorphies alleged to distinguish the Aublysodontinae, especially lack of serrations on premaxillary teeth could have been caused by tooth wear in life, postmortem abrasion, or digestion. Most other "aublysodontine"-type teeth may be from ontogenetic stages or sexual morphs of other tyrannosaurids.
Agathaumas is a dubious genus of a large ceratopsid dinosaur that lived in Wyoming during the Late Cretaceous. The name comes from Ancient Greek: αγαν - 'much' and θαυμα - 'wonder'. It is estimated to have been 9 metres (30 ft) long and weighed 6 tonnes, and was seen as the largest land animal known at the time of its discovery.
Zapsalis is a genus of dromaeosaurine theropod dinosaurs. It is a tooth taxon, often considered dubious because of the fragmentary nature of the fossils, which include teeth but no other remains.
Paronychodon was a theropod dinosaur genus. It is a tooth taxon, often considered dubious because of the fragmentary nature of the fossils, which include "buckets" of teeth from many disparate times and places but no other remains, and should be considered a form taxon.
Omosaurus is a dubious genus of extinct crurotarsan reptile, possibly a phytosaur, from the Late Triassic (Carnian) of North Carolina. Only scant remains are known, which makes Omosaurus hard to classify. The type, and only species, Omosaurus perplexus, was named and described in 1856 by Joseph Leidy.
Diplotomodon is a dubious genus of theropod dinosaur, from New Jersey. It was possibly a member of the Tyrannosauroidea, the clade that also contains Tyrannosaurus.
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.
Dysganus (dis-GANN-us) is a dubious genus of ceratopsian dinosaur from the Campanian stage of the Late Cretaceous. The fossil teeth referred to Dysganus were first collected by Charles Sternberg from the Cretaceous Judith River Formation of Montana and later described by Edward Drinker Cope. All of the species are now seen as dubious Ceratopsians, though referred material from tyrannosaurids and hadrosaurids were found in New Mexico.
Diclonius is a genus of dinosaur from the Late Cretaceous. It was a hadrosaur based solely on teeth. Its fossils were found in the Judith River Formation of Montana, northern US. The name is in reference to the method of tooth replacement, in which newly erupting replacement teeth could be in functional use at the same time as older, more worn teeth. Thus, the number of "sprouting" teeth was doubled in comparison to Monoclonius, which used only one set of teeth at a time and which Cope named in the same paper.
Elasmosauridae is an extinct family of plesiosaurs, often called elasmosaurs. They had the longest necks of the plesiosaurs and existed from the Hauterivian to the Maastrichtian stages of the Cretaceous, and represented one of the two groups of plesiosaurs present at the end of the Cretaceous alongside Polycotylidae. Their diet mainly consisted of crustaceans and molluscs.
Woolungasaurus is a dubious genus of plesiosaur, an extinct marine reptile, belonging to the Elasmosauridae.
Ceratodus is an extinct genus lungfish. It has been described as a "catch all", and a "form genus" used to refer to the remains of a variety of lungfish belonging to the extinct family Ceratodontidae. Fossil evidence dates back to the Early Triassic. A wide range of fossil species from different time periods have been found around the world in places such as the United States, Argentina, Greenland, England, Germany, Egypt, Madagascar, China, and Australia. Ceratodus is believed to have become extinct sometime around the beginning of the Eocene Epoch.
Brimosaurus is an extinct genus of plesiosaur from the Late Cretaceous of what is now Arkansas. The type species is Brimosaurus grandis, first named by Joseph Leidy in 1854. The name Brimosaurus is a nomen dubium: the fossils consist of only a few isolated vertebrae, and in 1952 Welles proposed that Brimosaurus was actually synonymous with Cimoliasaurus.
Eurysaurus is an extinct genus of plesiosaur, originally classed as a nothosaur, from the Early Jurassic of Echenoz-la-Meline, France, named in 1878. The type material, consisting of a cranium, teeth and five vertebrae, is now lost. The type species is E. raincourti, and a second species, E. schafferi, was named in 1924 but it has since been absorbed into the unrelated genus Germanosaurus.
Germanosaurus, meaning "German lizard", is an extinct aquatic genus of nothosaurid sauropterygian known from the early Middle Triassic Lower Muschelkalk of what was known as Upper Silesia, now a part of Poland. The type species of Germanosaurus is G. latissimus, originally named as a species of Nothosaurus. After a new generic name was erected for it, the holotype fragmentary skull was lost, possibly during World War II. Rieppel (1997) thus considered the species to be a nomen dubium in the species. However, from surviving illustrations and descriptions of the material, he concluded that another taxon known as Cymatosaurus schafferi, is referable to Germanosaurus and possibly even represents the same species as G. latissimus. Rieppel removed the species from Cymatosaurus and created the new combination G. schafferi, making it the only valid species of Germanosaurus diagnosable to the species level.
