Fossils of animals including dinosaurs and stingrays more than 100 million years old have been unearthed in a Maryland park in what experts said could be the most extensive discovery of fossils of various species on the East Coast.
In April, a group of paleontologists and volunteers from the Department of Parks and Recreation in Prince George’s County, Maryland, found a 3-foot-long leg bone and classified it as one from a theropod, a branch of the dinosaur family that includes carnivores. Dinosaurs such as Tyrannosaurus rex.
“No carnivorous dinosaur of this size has ever been found on the east coast of the United States,” said JP Hudnett, a paleontologist for the Maryland-National Capital Park and Planning Commission.
“Finding a bony bottom like this is a dream for many paleontologists, as they can provide a wealth of information about the ancient environments that preserved fossils and provide more details about extinct animals that may have previously been known only from a handful of specimens,” he added.
“Bonebed” is a term used by paleontologists to describe the discovery of bones of one or more species concentrated within a geological layer. This was the first dinosaur bone bed to be discovered in Maryland since 1887.
The researchers connected the tibia bone to Acrocanthosaurus, the largest theropod of the early Cretaceous period estimated to be about 38 feet long, Mr. Hodnett said.
discovery, that was announced this weekhappened in Dinosaurs park, in South Laurel, Maryland, about 25 miles southwest of Baltimore. The bone bed was discovered during the Excavation Experiment Program, in which members of the public search for fossils.
Bone beds are uncommon on the East Coast, said Advit Jokar, a paleontologist at the University of Arizona, because the fossil finds were mostly isolated finds, such as claws or teeth.
d said. “We’ve never seen a site like this before.”
d said. He said the drought conditions there also help preserve them.
Fossils have been found at Dinosaur Park in Maryland from the mid-19th century, when the site was an iron mine. However, the most recent excavations date back to 2014.
Park staff discovered a large boulder, where some of the rock face had been cut away and appeared to have a fossil embedded in it. The boulder, 5 feet by 3 feet of ironstone, was a sedimentary rock that was difficult to work with, so the staff decided to let it erode naturally.
By 2018, they determined it was ready to be excavated, but the coronavirus pandemic delayed the project until 2021.
The dinosaur’s neck bones were the first significant discovery from the rock. In the years that followed, other fragments were found, including turtle skeletal fragments, isolated other dinosaur bones and some dinosaur and crocodile teeth.
Among the finds are fossils of Priconodon, a large, armored dinosaur. Ornithomimoid, an ostrich-like dinosaur. and Deinonychus, a predatory bird-like dinosaur. Hudnett said the researchers also found the remains of the oldest stingray in North America.
The findings will better inform paleontologists about what the ecosystem of that region of Maryland looked like during the Cretaceous period, said Adele Clumpmaker, curator of paleontology at the Alabama Museum of Natural History. He said the variety of different species found could help paleontologists understand the climate and food chain millions of years ago.
“It’s a whole group of animals that give a new window into what the United States looked like 115 million years ago,” said Dr. Clumpmaker.