Tugulusaurus
"Tugulu lizard"
- Lived
- 137 to 101 million years ago, Early Cretaceous
- Diet
- Carnivore
- Group
- Theropods
- Found in
- China
- Named by
- Dong 1973
Where its fossils were found
The evidence
Today
120 million years ago
Habitat
Lakes and muddy shores formed part of the landscape recorded by the Lianmuqin Formation in China. Psittacosaurus, Wuerhosaurus and Kelmayisaurus also lived in this region.
Field notes
About Tugulusaurus
What it was like
Tugulusaurus was a small meat eater known from parts of its legs, feet and hands. It is now thought to be an early alvarezsaur, a member of a group of bird-like dinosaurs that later had short arms with one large claw.
Its world
It lived in the Early Cretaceous in what is now northwestern China. Its bones come from the Lianmuqin Formation, where it shared the land with Psittacosaurus and the stegosaur Wuerhosaurus.
How it was found
Dong named Tugulusaurus in 1973. Its place was long unclear, and only later was it recognized as one of the first alvarezsaurs ever found.
Field gallery
More views of Tugulusaurus
Scenes reconstructed from the available fossil evidence.
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Lived alongside
Found in the same rock formations
A rock formation can hold fossils laid down millions of years apart, so not every animal here met Tugulusaurus.
The evidence
The science behind Tugulusaurus
Which parts of the picture come from its own bones, and which come from its relatives.
From its own fossils
- The partial skeleton includes tail vertebrae, a rib, parts of the hind legs and the first finger of each hand.
- Its tail vertebrae are unusually broad, and the bone at the base of the first finger is short and unevenly shaped. That finger ends in a strong, sharply curved claw.
- A toe claw, possibly from the third toe, is moderately curved and flat underneath. The thigh and shin bones are slender but poorly preserved.
Borrowed from relatives
- The missing shoulders, arms, neck, trunk and tail are restored by comparison with Xiyunykus, and the smaller outer fingers with Bannykus.
- The missing face follows Haplocheirus, an early alvarezsaur with a long, narrow, toothed snout.
Still unknown
- The shape of its skull and teeth.
- The rest of its hand. Studies number its big finger differently, as the first or the second.
- Its exact place among early alvarezsaurs. One study grouped it with Xiyunykus, while older analyses placed it differently.
Discovery timeline
- 1973Named itDong
- 2005RedescriptionRauhut & Xu
- 2018Family treeXu et al.
- 2024Family treeMeso et al.
Key papers
The research behind what we know of Tugulusaurus
Named it
Introduced Tugulusaurus as a small theropod from Early Cretaceous rocks in China.
[Dinosaurs from Wuerho]. Reports of Paleontological Expedition to Sinkiang (II): Pterosaurian Fauna from Wuerho, Sinkiang. Memoirs of the Institute of Vertebrate Paleontology and Paleoanthropology, Academia Sinica 11: 45-52
No link available
Redescription
Confirmed Tugulusaurus as a distinct dinosaur through its broad tail vertebrae and unusual first hand bone, and described its strong hand claw.
The small theropod dinosaursTugulusaurusandPhaedrolosaurusfrom the early Cretaceous of Xinjiang, China. Journal of Vertebrate Paleontology 25: 107-118
Read the paper : The small theropod dinosaursTugulusaurusandPhaedrolosaurusfrom the early Cretaceous of Xinjiang, China (opens in a new tab)Family tree
Placed Tugulusaurus among early alvarezsaurs while describing Bannykus and Xiyunykus, relatives that help explain the group's changing arms.
Two Early Cretaceous Fossils Document Transitional Stages in Alvarezsaurian Dinosaur Evolution. Current Biology 28: 2853-2860.e3
Read the paper : Two Early Cretaceous Fossils Document Transitional Stages in Alvarezsaurian Dinosaur Evolution (opens in a new tab)Family tree
Built a revised alvarezsaur family tree. In it Tugulusaurus grouped with Xiyunykus, with Bannykus close by.
Body size and evolutionary rate analyses reveal complex evolutionary history of Alvarezsauria. Cladistics 41: 135-155
Read the paper : Body size and evolutionary rate analyses reveal complex evolutionary history of Alvarezsauria (opens in a new tab)
Close relatives
Other members of Alvarezsauroidea
Sources: Wikidata