Now this is getting ridiculous.

Last week I wrote about how 2017 has seen an entire flock of small, feathery dinosaurs come out of China. Now, hot on the tufted heels of Liaoningvenator comes a related dinosaur who was also skittering around ancient Liaoning Province around 125 million years ago.

The dinosaur, named Daliansaurus liaoningensis by paleontologist Shen Caizhi and colleagues, is a delicate little thing curled up in a piece of Early Cretaceous stone. Whereas the skeleton of the related Liaoningvenator is curled forward, however, Daliansaurus is in the more typical dinosaur death pose with its head thrown back and tail turned upwards. More important for arranging evolutionary trees of China's little troodontid relatives, Daliansaurus seems to be distinct from its relatives on the basis of various skeletal traits - including an extra large claw on its fourth toe.

The announcement of still another troodontid from Liaoning, China only serves to highlight a growing conundrum.

As the authors themselves state, it's possible that paleontologists have inadvertently named the same species more than once - mistaking variations between individuals or differences in age as signs of different species. Then again, Shen and colleagues argue, it may be that these dinosaurs were undergoing an evolutionary radiation within a restricted geographic space. Maybe they followed each other in time, or somehow divvied up habitats by going after different resources. Given that the flow of dinosaurs from this part of China shows no sign of stopping, the mystery will only intensify.

Daliansaurus
The skeleton of Daliansaurus. Credit: Shen et al 2017

Fossil Facts

Name: Daliansaurus liaoningensis

Meaning: Daliansaurus means "Dalian lizard" in reference to the town, and liaoningensis is after the Chinese province where the fossil was found.

Age: Cretaceous, about 125 million years ago.

Where in the world?: Liaoning, China.

What sort of organism?: A troodontid dinosaur.

How much of the organism’s is known?: A nearly-complete, articulated skeleton.

Reference:

Shen, C., Lü, J., Liu, S., Kundrát, M., Brusatte, S., Gao, H. 2017. A new troodontid dinosaur from the Lower Cretaceous Yixian Formation of Liaoning Province, China. Acta Geologica Sinica. 91 (3): 763-780

Previous Paleo Profiles:

The Light-Footed Lizard
The Maoming Cat
Knight’s Egyptian Bat
The La Luna Snake
The Rio do Rasto Tooth
Bob Weir's Otter
Egypt's Canine Beast
The Vastan Mine Tapir
Pangu's Wing
The Dawn Megamouth
The Genga Lizard
The Micro Lion
The Mystery Titanosaur
The Echo Hunter
The Lo Hueco Titan
The Three-Branched Cicada
The Monster of Minden
The Pig-Footed Bandicoot
Hayden's Rattlesnake Demon
The Evasive Ostrich Seer
The Paradoxical Mega Shark
The Tiny Beardogs
The Armored Fish King
North America's Pangolin
The Invisible-Tusked Elephant
The Mud Dragon
The Spike-Toothed Salmon
The Dream Coast Crocodile
Buriol's Robber
Ozimek's Flyer
The Northern Naustoceratopsian
The High Arctic Flyer
The Tomatillo From the End of the World
The Short-Faced Hyena
The Mighty Traveler from Egg Mountain
Keilhau's Ichthyosaur
Mexico's Ancient Horned Face
Mauricio Fernández's Plesiosaur
New Zealand's Giant Dawn Penguin
The Orange Sea Lion
Mongolia's Ginkgo Cousin
The Geni River Frog
Isabel Berry's Dinosaur
The Whale Caiman
The Moab Lizard
Yang Zhongjian's Lizard
The Little Anubis
The Shuangbai Lizard
The Wyvern Dinosaur
The "Need Helmet" Dinosaur
The Jianianhua Dragon
The Liaoning Hunter