Chinese paleontologists have discovered fossil fragments of a new genus and species of stegosaur dinosaur. Bayinosaurus baojiensis.
Bayinosaurus baojiensis It roamed the Earth during the Middle Jurassic period, about 165 million years ago.
This dinosaur species is StegosaursA group of herbivorous armoured dinosaurs that lived in the Jurassic and Cretaceous periods.
Stegosaurus reached a maximum length of about 9 metres (30 feet). It had a small head with peg-like teeth, vertical bone plates and spines on its back and tail, and hoof-like toes on all four limbs.
“Stegosaurus is a minor but iconic lineage of ornithischian dinosaurs, but its early evolution remains poorly understood due to a poor fossil record,” said Dr Li Ning from China University of Geosciences and his colleagues.
“These dinosaurs are characterized by having two parasagittal rows of enlarged dermal armor plates and/or spines that extend from the neck to the tip of the tail, and have been found on every continent except Antarctica and Australia.”
“The earliest stegosaurs date to the Middle Jurassic and were distributed worldwide by the Late Jurassic, after which diversity declined during the Early Cretaceous.”
“Middle Jurassic stegosaurs are rarely recorded, with only five species. Loricatosaurus From the UK, Isabelisaura From Argentina, Adorati Krit From Morocco and Huayangosaurus and Bashanosaurus From China.”
Partial skeleton of Bayinosaurus baojiensis The fossil, consisting of a partial skull, one cervical vertebra, seven dorsal vertebrae, and one caudal vertebra, Wangjiashan Formation.
“The study area is located in the northwestern part of the Baojishan Basin, Pingchuan District, Baiyin City, Gansu Province, China,” the paleontologists said.
“The Baojishan Basin is located at the eastern end of the Qilian Mountains.”
According to the team's systematic analysis, Bayinosaurus baojiensis is an early diverging stegosaur, Isabelisaura, Alcovasaurus, Junjunosaurus and Gigantespinosaurus.
“Bayinosaurus baojiensis “This dinosaur possesses several protoplasmic features and represents a morphological transition between early ostracods and the early-diverging stegosaurs,” the researchers say.
“The increased diversity of Middle Jurassic stegosaurs and their early divergence position suggest that stegosaurs likely diverged from their sister taxon, the ankylosaurs, in the early Middle Jurassic (or possibly much earlier).”
of study Published in the journal Scientific Reports.
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L. Nin others2024. A new species of stegosaur (Dinosauria: Ornithischia) discovered from the Middle Jurassic of Gansu Province, China. Scientific Reports 14, 15241; doi: 10.1038/s41598-024-66280-x
Source: www.sci.news