Rhoetosaurus
Encyclopedia
Rhoetosaurus named after Rhoetus
, a titan
in Greek Mythology
, is a genus
of sauropod dinosaur
from the Jurassic
(?Middle Jurassic) of what is now eastern Australia
. Rhoetosaurus is estimated to have been about 12–15 metres long. Subsequent authors have sometimes misspelled the name: Rhaetosaurus (de Lapparent & Laverat, 1955); Rheteosaurus (Yadagiri, Prasad & Satsangi, 1979).
, learnt of a large fossil reptile skeleton exposed on Durham Downs Station near Roma
in central Queensland
. The station manager, Arthur Browne, forwarded fragments of bone to Longman, so and was honoured with the dinosaur's specific name brownei.
The initial collection was of 22 tail vertebrae, including a series of 16 consecutive bones, and other fragmentary hindlimb pieces. Soon after Longman announced the new discovery, he visited the station and arranged for more material of the same skeleton to be sent to the Queensland Museum. These included additional vertebrae from the thoracic area, bits of rib, more caudals and more of the femur and pelvis as well as a cervical vertebra.
Further material was collected by Mary Wade and Alan Bartholomai in 1975, and still more by Drs. Tom Rich, Anne Warren, Zhao Xijin, and Ralph Molnar. This additional material includes more ribs, another possible cervical vertebrae, and most of right hind limb, which is currently under study. To date, the end of the tail, forelimbs nor skull has not been found.
Rhoetosaurus is among the best-known sauropods thus far discovered in Australia
, as well as for the Jurassic
of Gondwana
.
, noted the primitive nature of Rhoetosaurus, and so for a long time, it was called a cetiosaurid. But this group is now simply considered an unnatural grab-bag of basal (primitive) sauropods. More recently, others have compared it to Shunosaurus
, based on similar general age, but without justification. Given its supposed relationship to Shunosaurus
, which had a clubbed tail, Rhoetosaurus has also been hypothesized to possess something similar. The form of the nearly complete hind foot (http://home.alphalink.com.au/~dannj/rhoefoot.jpg)at least suggests that lies outside the more derived Neosauropoda
, but the material needs further study to determine its precise positioning in sauropod evolution.
Rhoetus
Rhoetus was a character mentioned by Ovid in Book V of his mock-epic Metamorphoses.After Perseus rescues Andromeda from the sea monster, her betrothed Phineus, brother of her father, attacks Perseus, throwing a spear at him. Perseus, in turn, throws the spear back, but Phineus hides behind the...
, a titan
Titan (mythology)
In Greek mythology, the Titans were a race of powerful deities, descendants of Gaia and Uranus, that ruled during the legendary Golden Age....
in Greek Mythology
Greek mythology
Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...
, is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of sauropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
from the Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
(?Middle Jurassic) of what is now eastern Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. Rhoetosaurus is estimated to have been about 12–15 metres long. Subsequent authors have sometimes misspelled the name: Rhaetosaurus (de Lapparent & Laverat, 1955); Rheteosaurus (Yadagiri, Prasad & Satsangi, 1979).
Discovery and species
In 1924, Heber Longman, self-trained paleontologist at (and later director of) the Queensland Museum in BrisbaneBrisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...
, learnt of a large fossil reptile skeleton exposed on Durham Downs Station near Roma
Roma, Queensland
Roma is a town in the western Darling Downs area of Queensland, Australia, by rail WNW of Brisbane. It is situated at the junction of the Warrego and Carnarvon highways...
in central Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
. The station manager, Arthur Browne, forwarded fragments of bone to Longman, so and was honoured with the dinosaur's specific name brownei.
The initial collection was of 22 tail vertebrae, including a series of 16 consecutive bones, and other fragmentary hindlimb pieces. Soon after Longman announced the new discovery, he visited the station and arranged for more material of the same skeleton to be sent to the Queensland Museum. These included additional vertebrae from the thoracic area, bits of rib, more caudals and more of the femur and pelvis as well as a cervical vertebra.
Further material was collected by Mary Wade and Alan Bartholomai in 1975, and still more by Drs. Tom Rich, Anne Warren, Zhao Xijin, and Ralph Molnar. This additional material includes more ribs, another possible cervical vertebrae, and most of right hind limb, which is currently under study. To date, the end of the tail, forelimbs nor skull has not been found.
Rhoetosaurus is among the best-known sauropods thus far discovered in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, as well as for the Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
of Gondwana
Gondwana
In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...
.
Relationships
Initially Longman, with advice from leading German paleontologist Friedrich von HueneFriedrich von Huene
Friedrich von Huene was a German paleontologist who named more dinosaurs in the early 20th century than anyone else in Europe.-Biography:...
, noted the primitive nature of Rhoetosaurus, and so for a long time, it was called a cetiosaurid. But this group is now simply considered an unnatural grab-bag of basal (primitive) sauropods. More recently, others have compared it to Shunosaurus
Shunosaurus
Shunosaurus, meaning "Shu Lizard", is a genus of sauropod dinosaur from Middle Jurassic beds in Sichuan Province in China, 170 million years ago...
, based on similar general age, but without justification. Given its supposed relationship to Shunosaurus
Shunosaurus
Shunosaurus, meaning "Shu Lizard", is a genus of sauropod dinosaur from Middle Jurassic beds in Sichuan Province in China, 170 million years ago...
, which had a clubbed tail, Rhoetosaurus has also been hypothesized to possess something similar. The form of the nearly complete hind foot (http://home.alphalink.com.au/~dannj/rhoefoot.jpg)at least suggests that lies outside the more derived Neosauropoda
Neosauropoda
Neosauropoda is a division-level clade of sauropods within Dinosauria, and consists of the group leading to Diplodocoidea and Macronaria. Haplocanthosaurus was a typical basal neosauropod from around 150 million years ago, in the Late Jurassic...
, but the material needs further study to determine its precise positioning in sauropod evolution.