January 30, 2014
Penn Researchers Describe Newly Discovered Colossal Dinosaur
Lee Rannals for redOrbit.com - Your Universe Online
University of Pennsylvania paleontologists, publishing a paper in the journal PLOS ONE, say a new dinosaur discovered in northwestern China is colossal.
The team said the new species is a plant-eating sauropod named Yongjinglong datangi that roamed the earth more than 100 million years ago during the Early Cretaceous period. The fossils discovered belonged to a juvenile, roughly 50 to 60 feet long. The species is believed to belong to a group known as Titanosauria and anatomical evidence shows that adult members of Yongjinglong may grow larger than the fossils found in China.
The findings clarify relationships among several sauropod species that have been discovered around China over the last few decades. Yongjinglong’s features suggest that it is among the most evolutionary advanced of the Titanosaurs discovered from Asia.
The latest discovery was made in the southeastern Lanzhou-Minhe Basin of China's Gansu Province. Two other Titanosaurs from the same period were found in the last decade in a valley not far away from the latest discovery.
"As recently as 1997 only a handful of dinosaurs were known from Gansu," Prof Peter Dodson, from the University of Pennsylvania, said in a statement. "Now it's one of the leading areas of China. This dinosaur is one more of the treasures of Gansu."
When the paleontologists began studying the fossils, they saw that its bones bore some resemblance to another Titanosaur discovered in China in 1929, but there were a few unique characteristics that made it stand out.
"The shoulder blade was very long, nearly 2 meters (6 feet) with sides that were nearly parallel, unlike many other Titanosaurs whose scapulae bow outward," Liguo Li, a doctoral student at the University of Pennsylvania, said in a statement.
The team said the scapula was so long that it did not look like it fit in the animal’s body cavity if placed in a horizontal or vertical orientation. They believe the bone must have been orientated at an angle of 50 degrees from the horizontal.
An unfused portion of the shoulder blade indicated to the team that the animal was a juvenile or subadult. This means that a full-grown adult might be much larger than 50 to 60 feet long.
Finding Yongjinglong allows scientists to see where this dinosaur sits on the family tree of sauropods. The team compared the characteristics of Yongjinglong with other specimens found in China, Africa, South America and the US.
"We used standard paleontological techniques to compare it with phylogenies based on other specimens," Dodson said. "It is definitely much more derived than Euhelopus and shows close similarities to derived species from South America."
The team said that this finding adds weight to the argument that sauropods were a dominant group in the Early Cretaceous period.
"Based on U.S. fossils, it was once thought that sauropods dominated herbivorous dinosaur fauna during the Jurassic but became almost extinct during the Cretaceous," Dodson said. "We now realize that, in other parts of the world, particularly in South America and Asia, sauropod dinosaurs continued to flourish in the Cretaceous, so the thought that they were minor components is no longer a tenable view."
Image Below: A team led by University of Pennsylvania paleontologists has characterized a new dinosaur based on fossil remains found in northwestern China. The species, a plant-eating sauropod named Yongjinglong datangi, roamed during the Early Cretaceous period, more than 100 million years ago. Credit: University of Pennsylvania