Jobaria

Jobaria is a genus of sauropod dinosaur that lived in what is now Niger during the middle Jurassic Period, between 164–161 million years ago.[1]

Jobaria
Temporal range: Middle Jurassic, 167–161 Ma
Iziko Jobaria Dinosaur Skeleton Panorama
Skeletons of Jobaria and Suchomimus, two dinosaurs from Niger which did not coexist
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Saurischia
Suborder: Sauropodomorpha
Clade: Sauropoda
Clade: Eusauropoda
Genus: Jobaria
Sereno et al., 1999
Type species
Jobaria tiguidensis
Sereno et al., 1999

Description

Jobaria tiguidensis steveoc
Jobaria tiguidensis restoration

Jobaria was a primitive sauropod, about 18.2 metres (60 ft) long and estimated to weigh about 22.4 tonnes (24.7 short tons).[2] Its backbone and tail were simple compared to the complex vertebrae and whiplash tail of the later North America sauropods Diplodocus and Apatosaurus.

It may also have been able to rear up on its hind legs as Paul Sereno concluded, after comparing the ratios of humerus and femur circumferences in Jobaria to extant elephants.[3] The weight distribution of Jobaria indicates that it was supported by the rear limbs rather than the forelimbs (as in elephants) and is speculated that as elephants can rear up, then Jobaria would have been able to more easily.

Discovery

Jobaria cast
Cast mounted in rearing pose

Discovered in the fall of 1997, during a four-month expedition to the Sahara desert led by paleontologist Dr. Paul Sereno, it was found in a mass-death site in the Tiourarén Formation of Niger. With over 95% of its skeleton preserved it is among the most complete sauropods ever found.[4]

The genus is named after a local mythical giant beast, Jobar, whose bones some Tuaregs believed the fossils to be. The specific name tiguidensis comes from the cliff of Tiguidi, the site of discovery.[1]

The sediments in which it was found were originally thought to represent the Hauterivian to Barremian stages of the early Cretaceous Period, dating Jobaria to approximately 132 million years ago.[1] However, re-interpretation of the sediments showed that they are more likely from the Bathonian to Oxfordian stages of the middle Jurassic in age, between 167 and 161 million years ago.[5]

Classification

The phylogenetic relationships of Jobaria are uncertain; it has been interpreted either as a basal macronarian,[6] or as a non-neosauropod eusauropod, basal to the neosauropod clade.[7]

References

  1. ^ a b c Sereno, P.; et al. (November 1999). "Cretaceous Sauropods from the Sahara and the Uneven Rate of Skeletal Evolution Among Dinosaurs". Science. 286 (5443): 1342–1347. doi:10.1126/science.286.5443.1342. PMID 10558986.
  2. ^ Henderson, Donald (2013). "Sauropod Necks: Are They Really for Heat Loss?". PLoS ONE. 8 (10): e77108. doi:10.1371/journal.pone.0077108. PMC 3812985. PMID 24204747.
  3. ^ Could Sauropods Rear?
  4. ^ Sereno, Paul. "Discoveries: Jobaria tiguidensis". Archived from the original on 8 October 2012. Retrieved 25 September 2012.
  5. ^ Rauhut; Lopez-Arbarello (2009). "Considerations on the age of the Tiouaren Formation (Iullemmeden Basin, Niger, Africa): Implications for Gondwanan Mesozoic terrestrial vertebrate faunas". Palaeogeography, Palaeoclimatology, Palaeoecology. 271: 259–267. doi:10.1016/j.palaeo.2008.10.019.
  6. ^ Upchurch, P.; Barrett, P. M.; Dodson, P. (2004). "Sauropoda". The Dinosauria (2nd ed.). University of California Press.
  7. ^ Mannion, P.D.; Allain, R.; Moine, O. (2017). "The earliest known titanosauriform sauropod dinosaur and the evolution of Brachiosauridae". PeerJ. 5: e3217. doi:10.7717/peerj.3217. PMC 5417094.

External links

Brasilotitan

Brasilotitan is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous (early Maastrichtian) Adamantina Formation of Brazil. The type species is Brasilotitan nemophagus.

Daxiatitan

Daxiatitan is a genus of titanosaur dinosaur from the Lower Cretaceous of Lanzhou Basin, Gansu Province, northwestern China. It is known from fossils including several neck vertebrae, a shoulder blade, and a thigh bone.It was a very large dinosaur, estimated at 23–30 meters (75–98 feet). Like both Euhelopus and Huanghetitan, it had an enormously long neck.

Diplodocinae

Diplodocinae is an extinct subfamily of diplodocid sauropods that existed from the Late Jurassic to Early Cretaceous of North America, Europe and South America, about 161.2 to 136.4 million years ago. Genera within the subfamily include Tornieria, Supersaurus, Leinkupal, Galeamopus, Diplodocus, Kaatedocus and Barosaurus.Cladogram of the Diplodocidae after Tschopp, Mateus, and Benson (2015).

Eusauropoda

Eusauropoda (meaning "true sauropods") is a derived clade of sauropod dinosaurs. Eusauropods represent the node-based group that includes all descendant sauropods starting with the basal eusauropods of Shunosaurus, and possibly Barapasaurus, and Amygdalodon, but excluding Vulcanodon and Rhoetosaurus. The Eusauropoda was coined in 1995 by Paul Upchurch to create a monophyletic new taxonomic group that would include all sauropods, except for the vulcanodontids.Eusauropoda are herbivorous, quadrupedal, and have long necks. They have been found in South America, Europe, North America, Asia, Australia, and Africa. The temporal range of Eusauropoda ranges from the early Jurassic to the Latest Cretaceous periods. The most basal forms of eusauropods are not well known and because the cranial material for the Vulcanodon is not available, and the distribution of some of these shared derived traits that distinguish Eusauropoda is still completely clear.

Ferganasaurus

Ferganasaurus was a genus of dinosaur first formally described in 2003 by Alifanov and Averianov. The type species is Ferganasaurus verzilini. It was a sauropod similar to Rhoetosaurus. The fossils were discovered in 1966 in Kyrgyzstan from the Balabansai Formation and date to the Callovian stage of the Middle Jurassic.

Flagellicaudata

Flagellicaudata is a clade of Dinosauria. It belongs to Sauropoda and includes two families, the Dicraeosauridae and the Diplodocidae.

Gravisauria

Gravisauria is a clade of sauropod dinosaurs consisting of some genera, Vulcanodontidae and Eusauropoda.

Huangshanlong

Huangshanlong is a genus of mamenchisaurid dinosaurs native to the Anhui province of China. It contains a single species, Huangshanlong anhuiensis. H. anhuiensis represents, along with Anhuilong and Wannanosaurus, one of three dinosaurs fround in Anhui province.

Jiutaisaurus

Jiutaisaurus is a genus of sauropod dinosaur from the Quantou Formation of China. Jiutaisaurus was a sauropod which lived during the Cretaceous. The type species, Jiutaisaurus xidiensis, was described by Wu et al. in 2006, and is based on eighteen vertebrae.

Jobaria Defense Systems Multiple Cradle Launcher

The Jobaria Defense Systems Multiple Cradle Launcher, also called Jahanam Launcher (Arabic: الراجمة جهنم‎), is an Emirati made multiple rocket launcher unique to the United Arab Emirates Army. It has 240 tubes making it the world's largest rocket artillery by tube count. It is thought to function as a combined form of BM-21 Grad multiple rocket launcher. It is developed by a joint venture between Al Jaber Land System and Roketsan.

Kaijutitan

Kaijutitan (meaning "Kaiju titan" after the type of Japanese movie monsters) is a genus of basal titanosaur dinosaur from the Sierra Barrosa Formation from Neuquén Province in Argentina. The type and only species is Kaijutitan maui.

List of African dinosaurs

This is a list of dinosaurs whose remains have been recovered from Africa. Africa has a rich fossil record, but it is patchy and incomplete. It is rich in Triassic and Early Jurassic dinosaurs. African dinosaurs from these time periods include Coelophysis, Dracovenator, Melanorosaurus, Massospondylus, Euskelosaurus, Heterodontosaurus, Abrictosaurus, and Lesothosaurus. In the Middle Jurassic, the sauropods Atlasaurus, Chebsaurus, Jobaria, and Spinophorosaurus, flourished, as well as the theropod Afrovenator. The Late Jurassic is well represented in Africa, mainly thanks to the spectacular Tendaguru Formation. Veterupristisaurus, Ostafrikasaurus, Elaphrosaurus, Giraffatitan, Dicraeosaurus, Janenschia, Tornieria, Tendaguria, Kentrosaurus, and Dysalotosaurus are among the dinosaurs whose remains have been recovered from Tendaguru. This fauna seems to show strong similarities to that of the Morrison Formation in the United States and the Lourinha Formation in Portugal. For example, similar theropods, ornithopods and sauropods have been found in both the Tendaguru and the Morrison. This has important biogeographical implications.

The Early Cretaceous in Africa is known primarily from the northern part of the continent, particularly Niger. Suchomimus, Elrhazosaurus, Rebbachisaurus, Nigersaurus, Kryptops, Nqwebasaurus, and Paranthodon are some of the Early Cretaceous dinosaurs known from Africa. The Early Cretaceous was an important time for the dinosaurs of Africa because it was when Africa finally separated from South America, forming the South Atlantic Ocean. This was an important event because now the dinosaurs of Africa started developing endemism because of isolation.

The Late Cretaceous of Africa is known mainly from North Africa. During the early part of the Late Cretaceous, North Africa was home to a rich dinosaur fauna. It includes Spinosaurus, Carcharodontosaurus, Rugops, Bahariasaurus, Deltadromeus, Paralititan, Aegyptosaurus, and Ouranosaurus.

Mamenchisauridae

Mamenchisauridae is a family of sauropod dinosaurs known from the Jurassic and Early Cretaceous of Asia and Africa.

Microcoelus

Microcoelus is a dubius genus of small Titanosaurian sauropod dinosaur native to Argentina. It is known from only a single dorsal vertebra. A left humerus was formerly referred to this species, but it is now considered to belong to Neuquensaurus. This species may be a synonym of the contemporary sauropod Neuquensaurus australis.It was described by British paleontologist Richard Lydekker in 1893.

Pilmatueia

Pilmatueia is a diplodocoid sauropod belonging to the family Dicraeosauridae that lived in Argentina during the Early Cretaceous.

Spinophorosaurus

Spinophorosaurus is a genus of sauropod dinosaur that lived in what is now Niger during the Middle Jurassic period. The first two specimens were excavated in the 2000s by German and Spanish teams under difficult conditions. The skeletons were brought to Europe and digitally replicated, making Spinophorosaurus the first sauropod to have its skeleton 3D printed, and were to be returned to Niger in the future. Together, the two specimens represented most of the skeleton of the genus, and one of the most completely known basal sauropods of its time and place. The first skeleton was made the holotype specimen of the new genus and species Spinophorosaurus nigerensis in 2009; the generic name ("spine-bearing lizard") refers to its spiked osteoderms, and the specific name refers to where it was found. A juvenile sauropod from the same area was later assigned to the genus.

The subadult holotype specimen is estimated to have been around 13 m (43 ft) in length, whereas the paratype was about 14 m (46 ft) long. The shoulder height reached by these individuals was estimated at around 4 m (13 ft), and the weight at about 7 metric tons (7.7 short tons). The braincase was short, deep, and broad, and the neuroanatomy was in some ways intermediate between that of basal sauropodomorphs and the more derived neosauropods. The teeth were spatulate (spoon shaped) and had large spaced denticles at the top of the crown, an ancestral feature in sauropods. The neck of Spinophorosaurus is one of the most completely known among sauropods, containing 13 vertebrae. The dorsal vertebrae had multiple small, air-filled internal chambers, a feature typical of later, more derived sauropods. The tail was powered by strong musculature and had a rear section that was rather rigid due to long and overlapping chevron bones. Osteoderms bearing spikes appear to have been placed on the tail tip in two pairs); a similar feature is seen in the related Shunosaurus.

Spinophorosaurus has been classified as either a very basal sauropod, or inside Eusauropoda, a more derived group. The anatomy, age, and location of specimens indicate that important developments in sauropod evolution may have occurred in North Africa, possibly controlled by climatic zones and plant biogeography. Features of the vestibular apparatus suggest that vision and coordinated eye, head, and neck movements were important in Spinophorosaurus. Due to the completeness of Spinophorosaurus, 3D models have been made of the skeleton, and used to test its range of motion. One study suggests it may have been a high browser, and another examined possible mating postures. The spikes on the tail may have been used for defence. Sutures between the neural arches with the centra of the vertebrae were more complex in the front part of the trunk of Spinophorosaurus, since stresses were probably greatest in that region. Spinophorosaurus is known from the Irhazer Shale, a geological formation thought to be Middle Jurassic in age. It was formed by deposits from rivers and lakes in a great river-valley system.

Tambatitanis

Tambatitanis is an extinct genus of titanosauriform dinosaur from the Early Cretaceous (probably early Albian) of Japan. It is known from a single type species, Tambatitanis amicitiae. It was probably around 14 meters long and its mass was estimated at some 4 tonnes. It was a basal titanosauriform and possibly belonged to the Euhelopodidae.

Tengrisaurus

Tengrisaurus (meaning "Tengri lizard") is a genus of lithostrotian sauropod, from the Early Cretaceous (Barremian-Aptian), of the Murtoi Formation, Russia. It was described in 2017 by Averianov & Skutschas. The type species is T. starkovi.

Vulcanodontidae

The Early Jurassic sauropod dinosaurs Zizhongosaurus, Barapasaurus, Tazoudasaurus, and Vulcanodon may form a natural group of basal sauropods called the Vulcanodontidae. Basal vulcanodonts include some of the earliest known examples of sauropods. The family-level name Vulcanodontidae was erected by M.R. Cooper in 1984. In 1995 Hunt et al. published the opinion that the family is synonymous with the Barapasauridae. One of the key morphological features specific to the family is an unusually narrow sacrum.

Languages

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.