New Species of DuckBilled Dinosaur Identified

first_imgStay on target Scientists Uncover New Evidence of Asteroid That Killed DinosaursEgg Fossils Provide Glimpse Into Prehistoric Parenting The most complete skull of a duck-billed dinosaur discovered in Big Bend National Park turns out to be a new genus and species.Aquilarhinus palimentus, named for its beaked nose and wide lower jaw, is described in a paper published this week by the Journal of Systematic Palaeontology.Texas Tech University professor Tom Lehman was a lowly Master’s student conducting research on rock layers at Rattle Snake Mountain in the 1980s when he found badly weathered bones.Some stuck together (and therefore impossible to study), the fossils were thought to be distinctive of the hadrosaurid Gryposaurus.It wasn’t until a recent analysis, though, that scientists realized the specimen was even older than either of the two major groups of duck-billed dinosaurs.The dentary of Aquilarhinus, showing the unusual upturned end of the mandible (via Albert Prieto-Marquez)“This new animal is one of the more primitive hadrosaurids known, and can therefore help us to understand how and why the ornamentation on their heads evolved, as well as where the group initially evolved and migrated from,” according to lead study author Albert Prieto-Márquez, from the Institut Català de Paleontologia Miquel Crusafont, near Barcelona.“Its existence adds another piece of evidence to the growing hypothesis, still up in the air, that the group began in the southeastern area of the US,” he added.Herbivorous duck-billed dinosaurs, also known as hadrosaurids, all had similar-looking snouts: The front of the jaws met in a U-shape to support a cupped beak used for cropping plants.Sure, some beaks were broader than others, but there was no evidence of a significantly different shape, and therefore different feeding style—until Aquilarhinus came along.Illustration of Aquilarhinus palimentus (via ICRA Art)Unlike its later counterparts, the primordial creature’s lower jaws met in a “peculiar” W-shape, creating a wide, flattened scoop, useful for shovelling through loose, wet sediment and scooping loosely rooted aquatic plants.The outsider doesn’t fit with the preeminent Saurolophidae group of duck-billed dinos, though both sported bony cranial crests of varying shapes and sizes.This discovery supports the hypothesis that all crests derived from a common ancestor with a simple humped nose.More on Massive Dinosaur Skeleton Would Look Great In Your FoyerConstruction Workers Unearth Dinosaur Fossils in Denver SuburbFossil Discovery Offers Glimpse Into ‘Dinosaur-Killer’ Impactlast_img read more