Scientists have identified a new species and genus of mainly herbivorous dinosaurs that lived about 72 million years ago based on fossils unearthed on Hokkaido, Japan’s northern island.
The new dinosaur named Paralitherizinosaurus japonicusroamed the Earth during the Upper Cretaceous period about 72 million years ago, according to the study published in the journal earlier this month Scientific Reports.
It belonged to a family of small to large, mostly herbivorous theropod dinosaurs called Therizinosauridae, scientists say, including those from the University of Hokkaido in Japan.
“Therizinosaurs have been found mainly in the Cretaceous deposits of Mongolia and China,” the researchers said, adding, with the exception of the dinosaur falcariusm, All Early Cretaceous species have been named from China so far.
Two other species, they said, were recovered from the north (Alxasaurus from Inner Mongolia) and northwest (Suzhousaurus from Gansu Province) regions.
“Other Chinese Species (jianchangosaurus, Beipiaosaurusand Lingyuanosaurus) were recovered by the Jehol group in China’s Liaoning province in the east of the country,” the researchers added.
While fragmentary fossils of therizinosaurs from Japan are known, scientists said the taxonomic status of these dinosaurs remained unresolved.
They said such fossils were located on the eastern edge of the Asian continent during the Cretaceous period, before the opening of the Sea of Japan during the Miocene, which spanned from about 23 million years to 5.3 million years ago.
One such specimen, collected from the Osoushinai Formation in the city of Nakagawa in Hokkaido Prefecture, has been previously identified as a maniraptoran dinosaur and a potential therizinosaur, scientists said.
In the new study, the researchers re-examined the specimen and identified it as a new species of therizinosaur.
“Paralitherizinosaurus japonicus is the third therizinosaur specimen from Japan, after a single tooth from Honshu island and a partial skull, teeth and humerus from Kyushu island,” they said.
Scientists said the dinosaur belonged to a new taxon based on new evidence it had distinct features in its limbs and claws.
“Our study shows that it is a new taxon, Paralitherizinosaurus japonicus Gen. et sp. nov. because it exhibits a unique combination of features in the metacarpals and tongues,” the researchers wrote in the study.
They said the species is also the youngest therizinosaur from Japan and the first to be recovered from marine deposits in Asia.
“This suggests a long temporal existence of therizinosaurs on the eastern edge of the Asian continent and an adaptation of therizinosaurs to coastal environments,” the researchers added.
https://www.independent.co.uk/news/science/japan-new-dinosaur-species-discovered-b2085868.html New dinosaur species discovered from fossils unearthed in Japan