Siluosaurus
Encyclopedia
Siluosaurus is a genus
of ornithopod
dinosaur
from the Barremian
-Albian
-age Lower Cretaceous Xinminbao Group
of Gansu
, China
. It is based on IVPP V.11117 (1-2)
, two teeth
. It is an obscure genus, with no papers doing more than mentioning it since it was described.
-Japan
ese Silk Road
Dinosaur Expedition. One tooth, seven millimetres long, was from the upper beak (premaxilla
), and the other, 3.7 millimetres high, was from the cheek region of the upper jaw (maxilla
). Dong Zhiming
, who named the genus in 1997, suggested that it was a hypsilophodont
id, and described the teeth as the smallest ornithopod teeth yet known. The type species
is Siluosaurus zhanggiani. The specific name honours Zhang Qian
, the Chinese diplomat who reconnoitred the Silk Road in the second century B.C. It was regarded without comment as a dubious name
in the most recent review of basal
ornithopods, a not-uncommon fate for dinosaur names based on teeth.
. Its size has not been estimated, but as most adult hypsilophodonts were 1–2 meters long (3.3-6.6 ft), this genus would have been of similar to smaller size, based on Dong's comments.
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 ornithopod
Ornithopod
Ornithopods or members of the clade Ornithopoda are a group of ornithischian dinosaurs that started out as small, bipedal running grazers, and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous world, and dominated the North American...
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 Barremian
Barremian
The Barremian is an age in the geologic timescale between 130.0 ± 1.5 Ma and 125.0 ± 1.0 Ma). It is a subdivision of the Early Cretaceous epoch...
-Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
-age Lower Cretaceous Xinminbao Group
Xinminbao Group
The Xinminbao Group is a group of geological formations in north central China. They occur across a large depression between the Altai mountains of Mongolia to the north and the Qilian mountains of the Qinghai Plateau to the south, in the Gonpoquan and Suanjingze basins, and also in the...
of Gansu
Gansu
' is a province located in the northwest of the People's Republic of China.It lies between the Tibetan and Huangtu plateaus, and borders Mongolia, Inner Mongolia, and Ningxia to the north, Xinjiang and Qinghai to the west, Sichuan to the south, and Shaanxi to the east...
, China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
. It is based on IVPP V.11117 (1-2)
Institute of Vertebrate Paleontology and Paleoanthropology
The Institute of Vertebrate Paleontology and Paleoanthropology of China is a prominent research institution and collections repository for fossils, including many dinosaur and pterosaurand cat poo specimens...
, two teeth
Tooth
Teeth are small, calcified, whitish structures found in the jaws of many vertebrates that are used to break down food. Some animals, particularly carnivores, also use teeth for hunting or for defensive purposes. The roots of teeth are embedded in the Mandible bone or the Maxillary bone and are...
. It is an obscure genus, with no papers doing more than mentioning it since it was described.
History
The teeth that would be named Siluosaurus were recovered during the 1992 SinoChina
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
-Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
ese Silk Road
Silk Road
The Silk Road or Silk Route refers to a historical network of interlinking trade routes across the Afro-Eurasian landmass that connected East, South, and Western Asia with the Mediterranean and European world, as well as parts of North and East Africa...
Dinosaur Expedition. One tooth, seven millimetres long, was from the upper beak (premaxilla
Premaxilla
The incisive bone is the portion of the maxilla adjacent to the incisors. It is a pair of small cranial bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. They are connected to the maxilla and the nasals....
), and the other, 3.7 millimetres high, was from the cheek region of the upper jaw (maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
). Dong Zhiming
Dong Zhiming
Dong Zhiming , from the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, is one of China's leading paleontologists. He began working at the IVPP in 1962, learning from Yang Zhongjian who was director at the time...
, who named the genus in 1997, suggested that it was a hypsilophodont
Hypsilophodont
Hypsilophodonts were small ornithopod dinosaurs, regarded as fast, herbivorous bipeds on the order of 1–2 meters long . They are known from Asia, Australia, Europe, New Zealand, North America, and South America, from rocks of Middle Jurassic to late Cretaceous age...
id, and described the teeth as the smallest ornithopod teeth yet known. The type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
is Siluosaurus zhanggiani. The specific name honours Zhang Qian
Zhang Qian
Zhang Qian was an imperial envoy to the world outside of China in the 2nd century BCE, during the time of the Han Dynasty...
, the Chinese diplomat who reconnoitred the Silk Road in the second century B.C. It was regarded without comment as a dubious name
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
in the most recent review of basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
ornithopods, a not-uncommon fate for dinosaur names based on teeth.
Paleobiology
As a hypsilophodontid or other basal ornithopod, Siluosaurus would have been a bipedal herbivoreHerbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
. Its size has not been estimated, but as most adult hypsilophodonts were 1–2 meters long (3.3-6.6 ft), this genus would have been of similar to smaller size, based on Dong's comments.
External links
- Siluosaurus in The Dinosaur Encyclopaedia at Dino Russ's Lair
- Siluosaurus at Thescelosaurus!, under Ornithopoda i.s.