| Wamweracaudia Temporal range: Late Jurassic | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | † Sauropodomorpha |
| Clade: | † Sauropoda |
| Family: | † Mamenchisauridae |
| Genus: | † Wamweracaudia Mannion et al, 2019 |
| Species: | †W. keranjei |
| Binomial name | |
| †Wamweracaudia keranjei Mannion et al., 2019 | |
Wamweracaudia is a large herbivorous sauropod dinosaur from the Late Jurassic Tendaguru Formation of Tanzania, Africa, 155-145 million years ago.
During the German expeditions to the Tendaguru in German East Africa between 1909 and 1912, paleontologist Werner Janensch supervised the excavation of a sauropod tail at "Site G". In 1929, he referred this tail to Gigantosaurus robustus. [1]
In 1991, G. robustus was made the separate genus Janenschia . [2] Janensch had referred the tail based on personal observation of a series of finds of comparable material. During the Second World War much of this was destroyed; also most of his field notes were lost. In a revision of the genus Janenschia by José Fernando Bonaparte e.a. in 2000, it was concluded that the tail no longer overlapped known extant Janenschia fossils while the remaining documentation was insufficient to justify a referral. [3] In their study of the osteology of Lusotitan in 2013, Mannion et alii again excluded the tail, specimens MB.R.2091.1–30, from Janenschia due to its lack of overlap with its holotype SMNS 12144. They suggested that it may represent the first record of Mamenchisauridae from outside Asia. [4]
The specimen was in 2019 given the new genus and species name Wamweracaudia keranjei by Philip D. Mannion, Paul Upchurch, Daniela Schwarz and Oliver Wings in their re-appraisal of Janenschia and other presumed titanosaur finds from the Tendaguru. The generic name combines a reference to the Wamwera, a tribe inhabiting the region of the find, with a Latin cauda, "tail". The specific name honours the native foreman leading the team that excavated the tail, Mohammadi Keranje. [5]
Wamweracaudia is known from the holotype MB.R.2091.1–30, MB.R.3817.1 & MB.R.3817.2, found in a layer of the Tendagaru Formation dating from the Tithonian. It consists of an almost continuous series of thirty front and middle tail vertebrae, two neural spines of front tail vertebrae, and two chevrons. The tail vertebrae are numbered such that MB.R.2091.30 is the most anterior vertebra of the known series — though not necessarily the first tail vertebra — and MB.R.2091.1 the last one. Probably one vertebra is missing from the series. [5]
The describing authors established four autapomorphies, unique derived traits. With the front and middle tail vertebrae, the upper surface is excavated at its rear. With the front tail vertebrae, the neural processes show a rough zone on the upper third part of their side surface, separated from the rough zone of the rear surface by a vertical groove. With the middle to rear vertebrae, the underside is strongly pinched transversely, forming a ridge instead of a distinct flat surface. With the middle to rear vertebrae, the neural processes show an elongated horizontal ridge on their sides, just above the level of the prezygapophyses, the front articulation processes. [5]
Two additional traits are autapomorphies if Wamweracaudia is indeed a mamenchisaurid. The transverse processes or caudal ribs of the front tail vertebrae strongly curve sideways and to the front. With the front tail vertebrae, just in between the outer side of the prezygapophysis and the tip of the upper side of the diapophysis, the top rib facet, a pair of small extensions, or tubercula, is present. [5]
An exact cladistic analysis, part of the 2019 study, showed that Wamweracaudia was placed in the Mamenchisauridae, as a sister species of Mamenchisaurus . The two taxa shared procoelous tail vertebrae. These are also present in the Titanosauria and when the tail was still referred to it, Janeschia had been seen as one of the earliest known titanosaurs. [5]
As a sauropod, Wamweracaudia would have been a large quadrupedal herbivore. [6]
Kentrosaurus is a genus of stegosaurid dinosaur from the Late Jurassic in Lindi Region of Tanzania. The type species is K. aethiopicus, named and described by German palaeontologist Edwin Hennig in 1915. Often thought to be a "primitive" member of the Stegosauria, several recent cladistic analyses find it as more derived than many other stegosaurs, and a close relative of Stegosaurus from the North American Morrison Formation within the Stegosauridae.
Titanosaurs were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still thriving at the time of the extinction event at the end of the Cretaceous. This group includes some of the largest land animals known to have ever existed, such as Patagotitan—estimated at 37 m (121 ft) long with a weight of 69 tonnes —and the comparably-sized Argentinosaurus and Puertasaurus from the same region.
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.
Giraffatitan is a genus of sauropod dinosaur that lived during the late Jurassic Period in what is now Lindi Region, Tanzania. It was originally named as an African species of Brachiosaurus (B. brancai), but this has since been moved to its own genus. Giraffatitan was for many decades known as the largest dinosaur but recent discoveries of several larger dinosaurs prove otherwise; giant titanosaurians appear to have surpassed Giraffatitan in terms of sheer mass. Also, the sauropod dinosaur Sauroposeidon is estimated to be taller and possibly heavier than Giraffatitan.
Janenschia is a large herbivorous sauropod dinosaur from the Late Jurassic Tendaguru Formation of Lindi Region, Tanzania around 155 million years ago.
Andesaurus is a genus of basal titanosaurian sauropod dinosaur which existed during the middle of the Cretaceous Period in South America. Like most sauropods, belonging to one of the largest animals ever to walk the Earth, it would have had a small head on the end of a long neck and an equally long tail.
Tornieria is a genus of diplodocid sauropod dinosaur from the Late Jurassic in Lindi Region of Tanzania. It has a convoluted taxonomic history.
Tendaguria is a genus of herbivorous sauropod dinosaur from the Late Jurassic of Lindi Region, Tanzania.
Lusotitan is a genus of herbivorous brachiosaurid sauropod dinosaur from the Late Jurassic Period of Portugal.
Puertasaurus is a genus of sauropod dinosaur that lived in South America during the Late Cretaceous Period. It is known from a single specimen recovered from sedimentary rocks of the Cerro Fortaleza Formation in southwestern Patagonia, Argentina, which probably is Campanian or Maastrichtian in age. The only species is Puertasaurus reuili. Described by the paleontologist Fernando Novas and colleagues in 2005, it was named in honor of Pablo Puerta and Santiago Reuil, who discovered and prepared the specimen. It consists of four well-preserved vertebrae, including one cervical, one dorsal, and two caudal vertebrae. Puertasaurus is a member of Titanosauria, the dominant group of sauropods during the Cretaceous.
Camarasauridae is a family of sauropod dinosaurs. Among sauropods, camarasaurids are small to medium-sized, with relatively short necks. They are visually identifiable by a short skull with large nares, and broad, spatulate teeth filling a thick jaw. Based on cervical vertebrae and cervical rib biomechanics, camarasaurids most likely moved their necks in a vertical, rather than horizontal, sweeping motion, in contrast to most diplodocids.
Australodocus is a genus of sauropod dinosaur that lived during the Late Jurassic period, around 150 million years ago, in what is now Lindi Region, Tanzania. Though initially considered a diplodocid, recent analyses suggest it may instead be a titanosauriform.
Lithostrotia is a clade of derived titanosaur sauropods that lived during the Early Cretaceous and Late Cretaceous. The group was defined by Upchurch et al. in 2004 as the most recent common ancestor of Malawisaurus and Saltasaurus and all the descendants of that ancestor. Lithostrotia is derived from the Ancient Greek lithostros, meaning "inlaid with stones", referring to the fact that many known lithostrotians are preserved with osteoderms. However, osteoderms are not a distinguishing feature of the group, as the two noted by Unchurch et al. include caudal vertebrae with strongly concave front faces (procoely), although the farthest vertebrae are not procoelous.
Malarguesaurus is a genus of titanosauriform sauropod dinosaur from the Late Cretaceous of Mendoza Province, Argentina. Its fossils, consisting of tail vertebrae, chevrons, ribs, and limb bones, were found in the upper Turonian-lower Coniacian Portezuelo Formation of the Neuquén Group. The type species, described by González Riga et al. in 2008, is M. florenciae.
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.
Xianshanosaurus is a genus of sauropod dinosaur from the Early Cretaceous (Aptian-Albian) of the Ruyang Basin in Henan Province, China. Its type and only species is Xianshanosaurus shijiagouensis. It was described in 2009 by a team of paleontologists led by Lü Junchang. Xianshanosaurus may be a titanosaur, and Daxiatitan may be its closest relative, but its evolutionary relationships remain controversial.
Veterupristisaurus is an extinct genus of carcharodontosaurid theropod dinosaur known from the Jurassic of Tendaguru, Lindi Region of southeastern Tanzania.
Patagotitan is a genus of titanosaurian sauropod dinosaur from the Cerro Barcino Formation in Chubut Province, Patagonia, Argentina. The genus contains a single species known from at least six young adult individuals, Patagotitan mayorum, which was first announced in 2014 and then validly named in 2017 by José Carballido and colleagues. Preliminary studies and press releases suggested that Patagotitan was the largest known titanosaur and land animal overall, with an estimated length of 37 m (121 ft) and an estimated weight of 69 tonnes. Later research revised the length estimate down to 31 m (102 ft) and weight estimates down to approximately 50–57 tonnes, suggesting that Patagotitan was of a similar size to, if not smaller than, its closest relatives Argentinosaurus and Puertasaurus. Still, Patagotitan is one of the most completely-known titanosaurs, and so its interrelationships with other titanosaurs have been relatively consistent in phylogenetic analyses. This led to its use in a re-definition of the group Colossosauria by Carballido and colleagues in 2022.
Triunfosaurus is a genus of somphospondylan sauropod dinosaur from the Early Cretaceous of Brazil. It contains a single species, T. leonardii, described by Carvalho et al. in 2017. As a genus, Triunfosaurus can be distinguished from all other titanosaurs by the unique proportions of its ischium. It was initially described as a basal titanosaur, making it the earliest basal titanosaur known; however, subsequent research questioned the identification of the taxon as a titanosaur, instead reassigning it to the Somphospondyli.
Mierasaurus is an extinct genus of sauropod dinosaur from the Early Cretaceous of Utah, United States. The taxon was first described and named in 2017 by Rafael Royo-Torres and colleagues, from a mostly complete skeleton including a disarticulated partial skull and mandible, teeth, multiple vertebrae from along the length of the body, both scapulae, radius and ulna bones, a left manus, a complete pelvis, both femora and the entire left hindlimb. Additionally, they referred a lower jaw and femur from juvenile individuals, which were found nearby, to the genus. Collectively, Mierasaurus is among the most completely known North American sauropods. The genus name honours Bernardo de Miera y Pacheco, the first European scientist to enter what is now Utah. The type species for Mierasaurus is Mierasaurus bobyoungi, named after Robert Glen Young, a paleontologist who researched the Early Cretaceous of Utah.
