Yuanmouraptor jinshajiangensis strolled our world roughly 170 million years earlier(Middle Jurassic).

This dinosaur was a medium-sized member of the Metriacanthosauridae, a clade of meat-eating dinosaurs that resided on the ancient continental mass Laurasia throughout the Middle Jurassic to the Early Cretaceous.

“Metriacanthosauridae is a household of meat-eating dinosaurs and represents a basal-branching clade within the Allosauroidea,” stated Dr. Yi Zou, a paleontologist with the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences and the University of Chinese Academy of Sciences, and associates.

“Some looks into claim that metriacanthosaurids have closer relationship with carcharodontosaurids, rendering Metriacanthosauridae a more obtained group within Allosauroidea.”

“No matter what position Metriacanthosauridae has within Allosauroidea, members of this clade generally originated from the Middle to Late Jurassic strata of western China, such as Sichuan, Chongqing, Xinjiang, and Yunnan.”

“Apart from those types discovered in China, metriacanthosaurid theropods were likewise reported in the Late Jurassic of England, the Late Jurassic of Kyrgyzstan, and the Late Jurassic and Early Cretaceous of Thailand.”

“Recently, researchers reported a possible circulation of this clade in the Tibetan Plateau.”

The fossilized remains of Yuanmouraptor jinshajiangensis were gathered from the Zhanghe Formation in Yunnan province, China.

“The specimen consists of a fairly total skull and the very first 11 vertebrae consisting of 10 cervical vertebrae and the anterior-most dorsal vertebra,” the scientists stated.

“The maintained skull is determined 53.9 cm in anteroposterior length, and the restoration of the skull determines 60.1 cm in anteroposterior length.”

The group’s phylogenetic analysis positions the brand-new types at a basal-branching position within Metriancanthosauridae.

Yuanmouraptor jinshajiangensis provides the most total cranium amongst basal-branching tetanurans reported in Middle Jurassic China, and supplies important structural details worrying the uncommon mix of plesiomorphies and synapomorphies of cranium and cervical vertebrae in Metriacanthosauridae,” the researchers stated.

“In addition, our phylogenetic analysis recuperated the phylogenetic position of Piatnitzkysauridae being the sibling group to Avetheropoda rather of being within Megalosauroidea.”

“Three significant branches within Tetanurae are recuperated by our phylogenetic analysis with assistance of the monophyletic Avetheropoda (Allosauroidea + Coelurosauria) rather of the monophyletic Carnosauria (Megalosauroidea + Allosauroidea).”

“Due to the absence of agreement upon the phylogenetic relationship within basal-branching tetanurans over previous years and numerous fairly fragmentary products within Tetanurae, more precision in character coding and brand-new findings of early members of this clade are required to untangle the correlation of basal members of the group in the future.”

The discovery of Yuanmouraptor jinshajiangensis is reported in a paper released online in the journal PeerJ

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Y. Zou et al2025. A brand-new metriacanthosaurid theropod dinosaur from the Middle Jurassic of Yunnan Province, China. PeerJ 13: e19218; doi: 10.7717/ peerj.19218