[ad_1]
BIG BEND NATIONAL PARK, Tx (PRESS RELEASE) – Fossils discovered 35 years ago in Big Bend National Park have recently been identified as a new dinosaur species, Aquilarhinus palimentus.
This duckbill dinosaur is known for its aquiline nose and its wide lower jaw in the form of two juxtaposed trowels.
The fossil was discovered in the 1980s by Professor Tom Lehman of Texas Tech University. Bones have been severely altered and stuck together, making them impossible to study. Search in the
The 1990s revealed the presence of two arched nasal ridges considered to be distinctive of the genus Gryposaurus. At that time, the particular lower jaw was recognized, but it was only until a recent analysis that the researchers understood that the specimen was more primitive than Gryposaurus and all other saurolophid duckbill dinosaurs.
"This new animal is one of the most primitive hadrosaurids known, so it can help us understand how and why the ornamentation on the head has evolved, as well as the initial provenance of the group and its migration." explains Dr. Albert Prieto-, lead author. Márquez of the Institut Català de Paleontologia Miquel Crusafont, near Barcelona. "Its existence adds further evidence to the growing hypothesis, always in the air, that the band started in the southwestern United States."
The duckbilled dinosaurs, also called hadrosaurids, were the most common herbivorous dinosaurs in the late Mesozoic Era and all had a snout of similar appearance. The front of the jaws meet in a U-shape for
support a sectional beak used for growing plants. The beak of some species is wider than others, but there was no evidence of a significantly different form (and therefore probably of a different feeding style) until the discovery of Aquilarhinus. The lower jaws of Aquilarinus meet in a special W-shaped shape, creating a wide and flattened shovel. About 80 million years ago, this particular dinosaur would have shoveled
through wet, wet sediments to collect aquatic plants with loose roots from the tidal marshes of an ancient delta, where the Chihuahuan Desert is today.
The significance of this finding is that the jawbone and other characteristics of the specimen show that it does not correspond to the group of duckbill dinosaurs known as Saurolophidae.
This is more primitive than this group, suggesting that there may have been more primitive species than previously thought. The Saurophids had a cranial crest and the current specimen also had a bony crest, shaped like a hunchbacked nose. The discovery of a solid ridge outside the group confirms the hypothesis that both types of peaks evolved from a common ancestor.
These results have recently been published in the Journal of Systematic Paleontology and are available at http://www.tandfonline.com/10.1080/14772019.2019.1625078. The study was funded by the Ramon y Cajal program; the Ministry of Economy, Industry and Competitiveness of Spain; the CERCA program of the Generalitat de Catalunya; Texas Tech University; and the National Honor Society Sigma Xi scientist.
The work was done with permission from Big Bend National Park, as well as the Texas Vertebrate Paleontology Collections of the University of Texas at Austin, where the specimen is stored.
ILLUSTRATION BY ICRA ART
[ad_2]
Source link