Ultrasaurus Temporal range: Early Cretaceous, | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | † Sauropodomorpha |
Clade: | † Sauropoda |
Genus: | † Ultrasaurus Kim, 1983 [1] |
Species: | †U. tabriensis |
Binomial name | |
†Ultrasaurus tabriensis Kim, 1983 [1] | |
Synonyms | |
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Ultrasaurus (meaning "ultra lizard" [2] ) is a genus of sauropod dinosaur discovered by Haang Mook Kim in South Korea. However, the name was first used unofficially (as a nomen nudum ) in 1979 by Jim Jensen to describe a set of giant dinosaur bones he discovered in the United States. Because Kim published the name for his specimen before Jensen could do so officially, Jensen renamed his specimen Ultrasauros . Jensen's giant sauropod was later found to be a chimera, and the type remains are now assigned to Supersaurus .
A collection of bones discovered by Jim Jensen, of Brigham Young University, at the Dry Mesa Quarry, Colorado were originally believed to belong to the largest dinosaur ever. Jensen informally called this supposedly new dinosaur "Ultrasaurus", and this name was widely used by the press and in scientific literature as a nomen nudum (informal name lacking an actual scientific description).
In 1983, Kim Hang-mook published a paper describing a different specimen representing a new dinosaur species, which he named Ultrasaurus tabriensis, because he believed it was bigger than Supersaurus . However, Kim's assessment was incorrect. His dinosaur was much smaller than he believed, because he mistook a partial humerus for an ulna. However, since Kim was the first to publish the name Ultrasaurus, the name officially applied to the small South Korean sauropod, and could no longer be used as an official name for Jensen's giant specimen.
Jensen published a paper describing his original discovery in 1985, but since the name Ultrasaurus was already in use (or "preoccupied"), his discovery was renamed in 1991 to Ultrasauros. However, Jensen also made a mistake. His discovery was a chimera; the collection of fossils came from two different dinosaur species, both of which already had names. So his new name, Ultrasauros, is now just an alternate name (junior synonym) for the dinosaur officially known as Supersaurus, because the holotype of the Ultrasauros b
Ultrasaurus lived 100 to 110 million years ago, during the Aptian and Albian stages of the Early Cretaceous. It is known from the holotype DGBU-1973, which consists of part of an upper forearm (humerus), and DGBU-1978-A, a single tailbone (vertebrae) from the Gugyedong Formation, belonging to the Hayang Group. [1]
Kim's Ultrasaurus is currently a nomen dubium . Not enough is known about the specimen to formally assign it to a specific family of sauropods. [1]
Supersaurus is a genus of diplodocid sauropod dinosaur that lived in North America during the Late Jurassic period. The type species, S. vivianae, was first discovered by Vivian Jones of Delta, Colorado, in the middle Morrison Formation of Colorado in 1972. The fossil remains came from the Brushy Basin Member of the formation, dating between 153 to 145 million years ago. It is among the longest dinosaurs ever discovered, with the three known specimens reaching 33–40 meters (108–131 ft) in length, with the largest individual possibly exceeding 40 meters (130 ft) in size. Mass estimates for the WDC and BYU specimens tend to be around 35–44 metric tons in body mass. A potential second species, S. lourinhanensis (Dinheirosaurus), is known from Portugal and has been dated to a similar time.
Mamenchisaurus is a genus of sauropod dinosaur known for their remarkably long necks which made up nearly half the total body length. Numerous species have been assigned to the genus; however, the validity of these assignments has been questioned. Fossils have been found in the Sichuan Basin and Yunnan Province in China. Several species from the Upper Shaximiao Formation, whose geologic age is uncertain, have been described. However, evidence suggests this formation to be no earlier than the Oxfordian stage of the Late Jurassic. M. sinocanadorum dates to the Oxfordian stage, and M. anyuensis to the Aptian stage of the Early Cretaceous. Most species were medium-large to large sauropods, measuring roughly 15 to 26 meters in length—possibly up to 35 meters (115 ft), based on two undescribed vertebrae.
Yangchuanosaurus is an extinct genus of metriacanthosaurid theropod dinosaur that lived in China from the Middle Jurassic to Early Cretaceous periods, and was similar in size and appearance to its North American and European relative, Allosaurus. Yangchuanosaurus hails from the Upper Shaximiao Formation and Suining Formation and was the largest predator in a landscape that included the sauropods Mamenchisaurus and Omeisaurus and the stegosaurs Chialingosaurus, Tuojiangosaurus and Chungkingosaurus. This theropod was named after the area in which was discovered, Yongchuan, in China.
Pelorosaurus is a genus of titanosauriform sauropod dinosaur. Remains referred to Pelorosaurus date from the Early Cretaceous period, about 140-125 million years ago, and have been found in England and Portugal. Thomas Holtz estimated its length at 24 meters.
Antarctosaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. The type species, Antarctosaurus wichmannianus, and a second species, Antarctosaurus giganteus, were described by prolific German paleontologist Friedrich von Huene in 1929. Three additional species of Antarctosaurus have been named since then but later studies have considered them dubious or unlikely to pertain to the genus.
Argyrosaurus is a genus of titanosaurian sauropod dinosaur that lived about 70 million years ago, during the Late Cretaceous Period of what is now Argentina.
Cetiosaurus meaning 'whale lizard', from the Greek keteios/κήτειος meaning 'sea monster' and sauros/σαυρος meaning 'lizard', is a genus of herbivorous sauropod dinosaur from the Middle Jurassic Period, living about 168 million years ago in what is now Britain.
Crichtonsaurus is a genus of herbivorous ankylosaurid dinosaur that lived during the Late Cretaceous in what is now China. It was named after Michael Crichton, the author of the dinosaur novel Jurassic Park. A sister taxon was discovered, C. benxiensis, which is now identified as a separate genus.
Dinodocus is a genus of sauropod dinosaur, named by Richard Owen in 1884. The name is now usually considered a nomen dubium. The only species, D. mackesoni, a name given to some fossil bones from the Lower Greensand Group of Hythe, Kent, England, were formerly placed in the genus Pelorosaurus, but a review by Upchurch et al. (2004) concluded that Dinodocus is a nomen dubium.
Bashunosaurus is a genus of potentially macronarian sauropod dinosaur from the Middle Jurassic Shaximiao Formation of Kaijiang, China. The type and only species is Bashunosaurus kaijiangensis.
Sonorasaurus is a genus of brachiosaurid dinosaur from the Early to Late Cretaceous. It was a herbivorous sauropod whose fossils have been found in southern Arizona in the United States. Its name, which means "Sonora lizard", comes from the Sonora River that flows in the Sonoran Desert where its fossils were first found. The type species is S. thompsoni, described by Ratkevich in 1998.
James Alvin Jensen was an American paleontologist. His extensive collecting program at Brigham Young University in the Utah–Colorado region which spanned 23 years was comparable in terms of the number of specimens collected to that of Barnum Brown during the early 20th century. He was given the name "Dinosaur Jim" during the media coverage of his activities. Perhaps his most significant contribution to paleontology was to replace the 19th-century web of external metal struts, straps and posts that had been used to mount dinosaurs with a system of supports which were placed inside of bones, which produced free-standing skeletons with few or no obvious supports.
Amphicoelias is a genus of herbivorous sauropod dinosaur that lived approximately 150 million years ago during the Tithonian of what is now Colorado, United States. Amphicoelias was moderately sized at about 18 metres (59 ft) in length and 15 metric tons in body mass, shorter than its close relative Diplodocus. Its hindlimbs were very long and thin, and its forelimbs were proportionally longer than in relatives.
Brachiosaurus is a genus of sauropod dinosaur that lived in North America during the Late Jurassic, about 154 to 150 million years ago. It was first described by American paleontologist Elmer S. Riggs in 1903 from fossils found in the Colorado River valley in western Colorado, United States. Riggs named the dinosaur Brachiosaurus altithorax; the generic name is Greek for "arm lizard", in reference to its proportionately long arms, and the specific name means "deep chest". Brachiosaurus is estimated to have been between 18 and 22 meters long; body mass estimates of the subadult holotype specimen range from 28.3 to 46.9 metric tons. It had a disproportionately long neck, small skull, and large overall size, all of which are typical for sauropods. Atypically, Brachiosaurus had longer forelimbs than hindlimbs, which resulted in a steeply inclined trunk, and a proportionally shorter tail.
The Gugyedong Formation, also known as the Guyedong Beds, is an Aptian to Albian geologic formation in South Korea. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.
Paralititan was a giant titanosaurian sauropod dinosaur genus discovered in coastal deposits in the Upper Cretaceous Bahariya Formation of Egypt. It lived between 99.6 and 93.5 million years ago.
Maraapunisaurus is a genus of sauropod dinosaur from the Late Jurassic Morrison Formation of western North America. Originally named Amphicoelias fragillimus, it has sometimes been estimated to be the largest dinosaur specimen ever discovered. Based on surviving descriptions of a single fossil bone, scientists have produced numerous size estimates over the years; the largest estimate M. fragillimus to have been the longest known animal at 58 metres (190 ft) in length with a mass of 150 tonnes. However, because the only fossil remains were lost at some point after being studied and described in the 1870s, evidence survived only in contemporary drawings and field notes.
Australotitan is an extinct genus of possibly titanosaurian somphospondylan dinosaurs from the Late Cretaceous Winton Formation (Cenomanian–Turonian) of southern-central Queensland, Australia. The genus contains a single species, A. cooperensis, known from multiple partial skeletons. The genus Australotitan may be synonymous with Diamantinasaurus, a contemporary relative.