Saurornithoides
Encyclopedia
Saurornithoides is a genus
of troodontid
maniraptoran dinosaur
, living during the Late Cretaceous
period. These creatures were predator
s, which could run fast on their hind legs and had excellent sight and hearing. The name is derived from the Greek
stems sauros (lizard), ornithos (bird) and oid (form), an appropriate name for a creature close to the ancestry of birds.
Saurornithoides, like others in its family, was probably predominantly carnivorous. Estimates of its length range from 2 to 3 m (6.6 to 9.8 ft) and weight from 23 to 54 kg (50.7 to 119 lb). It had large eye sockets and stereoscopic vision, allowing for good depth perception. It probably had good vision in light and very good night vision. It had a long, low head, a depressed muzzle, sharp teeth and a relatively large brain. Swift and smart, like its North American cousin Troodon
, Saurornithoides probably scoured the Gobi Desert
, looking for small mammals or reptiles to eat. Scientists speculate that it used its long arms and grasping hands to seize live prey, which would have consisted of small animals. Like other troodontids, it had an especially large claw on the second toe of each foot.
A single specimen of this theropod has been found in the Djadochta Formation
of Mongolia
. Saurornithoides was named by paleontologist Osborn
in 1924. The type and only species is S. mongoliensis. A second species, S. junior, was named by Rinchen Barsbold in 1974, based on a larger specimen from the Nemegt Formation
thought to be more closely related to S. mongoliensis than to other troodonts. However, a 2009 review of the genus found that the support for this idea was lacking, and re-classified S. junior in the new genus Zanabazar
.
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 troodontid
Troodontidae
Troodontidae is a family of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and scrappy and they have therefore been allied, at various times, with many dinosaurian lineages...
maniraptoran 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...
, living during the Late Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
period. These creatures were predator
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
s, which could run fast on their hind legs and had excellent sight and hearing. The name is derived from the Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
stems sauros (lizard), ornithos (bird) and oid (form), an appropriate name for a creature close to the ancestry of birds.
Saurornithoides, like others in its family, was probably predominantly carnivorous. Estimates of its length range from 2 to 3 m (6.6 to 9.8 ft) and weight from 23 to 54 kg (50.7 to 119 lb). It had large eye sockets and stereoscopic vision, allowing for good depth perception. It probably had good vision in light and very good night vision. It had a long, low head, a depressed muzzle, sharp teeth and a relatively large brain. Swift and smart, like its North American cousin Troodon
Troodon
Troodon is a genus of relatively small, bird-like dinosaur from the Late Cretaceous period . Discovered in 1855, it was among the first dinosaurs found in North America...
, Saurornithoides probably scoured the Gobi Desert
Gobi Desert
The Gobi is a large desert region in Asia. It covers parts of northern and northwestern China, and of southern Mongolia. The desert basins of the Gobi are bounded by the Altai Mountains and the grasslands and steppes of Mongolia on the north, by the Hexi Corridor and Tibetan Plateau to the...
, looking for small mammals or reptiles to eat. Scientists speculate that it used its long arms and grasping hands to seize live prey, which would have consisted of small animals. Like other troodontids, it had an especially large claw on the second toe of each foot.
A single specimen of this theropod has been found in the Djadochta Formation
Djadochta Formation
The Djadochta Formation is situated in central Asia and dates from the Late Cretaceous Period. Laid down in the early Campanian, possibly starting in the latest Santonian, it is dated somewhat uncertainly at about 84-75 mya...
of Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
. Saurornithoides was named by paleontologist Osborn
Henry Fairfield Osborn
Henry Fairfield Osborn, Sr. ForMemRS was an American geologist, paleontologist, and eugenicist.-Early life and career:...
in 1924. The type and only species is S. mongoliensis. A second species, S. junior, was named by Rinchen Barsbold in 1974, based on a larger specimen from the Nemegt Formation
Nemegt Formation
The Nemegt Formation is a geological formation dating from the Late Cretaceous sedimentary from the Gobi Desert of Mongolia. It overlies and sometimes forms folds with the Barun Goyot Formation. It consists of river channel sediments and contains fossils of fish, turtles, crocodilians, birds and a...
thought to be more closely related to S. mongoliensis than to other troodonts. However, a 2009 review of the genus found that the support for this idea was lacking, and re-classified S. junior in the new genus Zanabazar
Zanabazar (dinosaur)
Zanabazar is a genus of troodontid dinosaur, which lived during the Late Cretaceous period in Mongolia.Fossils of this theropod have been found in the Nemegt Formation of Mongolia. Originally classified as a new species of the genus Saurornithoides by Rinchen Barsbold in 1974, based on a small...
.