Wamweracaudia Temporal range: Late Jurassic | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
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.
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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. Only one species is known, G. brancai, named in honor of German paleontologist Wilhelm von Branca, who was a driving force behind the expedition that discovered it in the Tendaguru Formation. Giraffatitan brancai was originally described by German paleontologist Werner Janensch as a species of the North American sauropod Brachiosaurus from the Morrison Formation, as Brachiosaurus brancai. Recent research shows that the differences between the type species of Brachiosaurus and the Tendaguru material are so large that the African material should be placed in a separate genus.
Janenschia is a large herbivorous sauropod dinosaur from the Late Jurassic Tendaguru Formation of Lindi Region, Tanzania around 155 million years ago.
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 of Portugal and possibly Spain.
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.
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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.
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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.
Mamenchisauridae is a family of sauropod dinosaurs belonging to Eusauropoda known from the Jurassic and Early Cretaceous of Asia and Africa. Some members of the group reached gigantic sizes, amongst the largest of all sauropods.
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