‘Beautifully preserved’ crested dinosaur skull found in New Mexico

Scientists have found an “exquisitely preserved” skull of a herbivorous dinosaur species in New Mexico, known for its strange head decoration.

The skull belongs to the iconic crested dinosaur Parasaurolophus, which lived during the late Cretaceous, about 76.5 million to 73 million years ago.

Parasaurolophus were herbivorous reptiles with trumpet-like nasal passages into which they breathed air through the so-called tube on their heads.

This particular skull belonged to a particular species of the genus Parasaurolophus – Parasaurolophus cyrtocristatus.

The newly revealed specimen would have been about 20 feet tall (6.1 meters) at the time and about 7.5 feet tall at the hip (2.3 meters).

Despite its extreme morphology, details of the specimen show that the crest is shaped like the crests of other related duckbill dinosaurs.

Parasaurolophus lived in lush, subtropical floodplains in one of two ancient landmasses that once existed North America, separated by a 2,000-mile stretch of water.

It coexisted with other crestless duckbill dinosaurs, horned dinosaurs and early tyrannosaurs alongside many emerging modern groups of alligators, turtles and plants.

“My jaw dropped when I first saw the fossil,” said Professor Terry Gates, a paleontologist at North Carolina State University.

‘I’ve been waiting for almost 20 years to see a copy of this quality.

Imagine your nose growing up in your face, three feet behind your head, then spinning around to suture above your eyes.

“Parasaurolophus breathed through eight feet of pipe before oxygen ever reached its head.”

The partial skull was discovered in 2017 by Erin Spear of the Smithsonian Tropical Research Institute, while exploring the badlands of northwestern New Mexico, but is only now being described by scientists.

Located deep in the Bisti / De-Na-Zin Wilderness of New Mexico, only a small portion of the skull was visible on a steep sandstone slope.

“ The preservation of this new skull is spectacular, finally revealing in detail the bones that make up the apex of this amazing dinosaur known to almost every dinosaur-obsessed child, ” said Joe Sertich, dinosaur curator at the Denver Museum of Nature and Science .

“This only reinforces the importance of protecting our public land for scientific discovery.”

Museum volunteers led by Sertich were surprised to find the intact crest while carefully chiseling the specimen from the sandstone.

One of the most recognizable dinosaurs, Parasaurolophus sported an elongated, tube-like crest on its head containing an internal network of airways.

“Over the past 100 years, ideas for the exaggerated tube crest have varied from snorkels to super sniffers,” said David Evans, the Temerty Chair in Vertebrate Palaeontology and Vice President of Natural History at the Royal Ontario Museum.

“But after decades of research, we now think these buds functioned primarily as sound resonators and visual displays used to communicate within their own species.”

Abundant bone fragments at the site indicated that much of the skeleton was once preserved on an ancient sandbar, but only the partial skull, part of the lower jaw and a handful of ribs have survived erosion.

“This specimen is truly remarkable in its preservation,” said Evans, who has worked on the Parasaurolophus dinosaur for nearly two decades.

It has answered long-standing questions about how the crest is constructed and about the validity of this particular species. This fossil is very exciting to me. ‘

Today, the badlands of northwestern New Mexico are dry and sparsely overgrown, a dramatic contrast to the lush low-lying floodplains preserved in their rocks that would have been the natural habitat of Parasaurolophus.

Seventy-five million years ago, when Parasaurolophus lived in the region, North America was divided into two landmasses by the Western Interior Seaway.

This shallow stretch of water ran from the Gulf of Mexico to the Arctic Ocean, and divided the continent into two landmasses – East America, or Appalachia, and West America, or Laramidia – for several million years.

Laramidia (in the west) stretched from present-day Alaska to central Mexico, where multiple episodes of mountain building took place in the early stages of the construction of today’s Rocky Mountains.

These mountain events have helped preserve diverse dinosaur ecosystems along their eastern flanks, some of the best preserved and most continuous anywhere in the world.

Thanks to several fossil finds, three species of Parasaurolophus are currently recognized, ranging from 77 million to 73.5 million years old.

The new skull is of P. cyrtocristatus, previously known from a single specimen collected in the same region of New Mexico in 1923 by the legendary American fossil hunter Charles H. Sternberg.

The other two recognized species of Parasaurolophus are P. walkeri (the remains of which are found in Alberta, Canada) and P. tubicen (remains of younger rocks in New Mexico).

“The original species of parasaurolophus, P. walkeri, dates back to 1921,” said Professor Gates.

‘Our Parasaurolophus [P. cyrtocristatus] is a different species, originally described in 1960 (but many years before being named).

“So this is the first P. cyrtocristatus that has been found and described in 60 years.”

P. cyrtocristatus was the smallest of the three species – overall, the newly described specimen is about 75 percent the size of the original P. walkeri found in 1921.

P. cyrtocristatus also has the most curved crest. The other two varieties had long buds with only a slight curvature.

The shorter, more curved apex of P. cyrtocristatus may be related to its immaturity at death, researchers said.

For decades, the Parasaurolophus family tree placed the two long, straight crested species (P. walkeri from Alberta and P. tubicen from New Mexico) as closely related, despite being more than 1,600 km and 2.5 million apart. years.

This new analysis, along with information from other Parasaurolophus discoveries from southern Utah, suggests for the first time that all southern New Mexico and Utah species may be more closely related than their northern cousin.

This fits patterns seen in other dinosaur groups of the same age, including horned dinosaurs.

“This specimen is a wonderful example of amazing creatures evolving from a single ancestor,” Sertich said.

The copy is further detailed in an article published in the journal PeerJ.