Paleontologists from the Fundación Conjunto Palaeontológico de Teruel-Dinopolis have published new findings in the scientific journal vertebrate zoology Description of an extraordinary stegosaur skull discovered in Riodeva (Teruel, Spain). The fossil, which comes from a plated dinosaur that lived about 150 million years ago, is also helping researchers propose a new explanation for how stegosaurs evolved and spread around the world.
Stegosaurs were plant-eating dinosaurs that walked on four legs and are known for the rows of plates and spikes running from their neck to tail. The newly studied fossil was uncovered during excavations led by the Fundación Dinopolis at the “Estan de Colón” site within the Villar del Arzobispo Formation, which dates to the Late Jurassic period.
Researchers identified the sample as Decentrurus armatusOne of Europe’s most iconic stegosaurs. This fossil is considered to be the best-preserved stegosaur skull ever discovered in Europe, which is a remarkable achievement as dinosaur skulls are extremely fragile and rarely remain intact for millions of years.
Sergio Sánchez Fenollosa, researcher at Fundación Dinopolis and co-author of the study, said: “The detailed study of this extraordinary fossil has allowed us to reveal previously unknown aspects of the anatomy. Decentrurus armatusThe quintessential European stegosaur, which will mark 150 years since its first description in 2025. Due to the extreme fragility of the bones of dinosaur skulls, they are rarely preserved. This discovery is key to understanding how stegosaurian skulls evolved.
“In addition, along with the anatomical studies, we have also proposed a new hypothesis that redefines the evolutionary relationships of stegosaurs worldwide. As a result of this work, we have formalized the definition of a new group called Neostegosauria.”
New dinosaur evolution hypothesis
Researchers say that Neostegosauria includes medium and large stegosaur species that lived on several continents during various periods of the Jurassic and early Cretaceous. According to the study, members of this group lived in what is now Africa and Europe during the Middle and Late Jurassic, North America during the Late Jurassic, and Asia during the Late Jurassic and Early Cretaceous.
The team believes this new classification could reshape the way scientists understand the evolutionary history and global distribution of plated dinosaurs.
Fossil site still making important discoveries
Alberto Cobos, managing director of Fundación Dinopolis and co-author of the research, emphasized the wider significance of the discovery: “This double achievement – the study of an extraordinary fossil and the proposal of a new evolutionary hypothesis – establishes this research as a global reference in stegosaurian studies.
“This fossil site of Riodeva remains the subject of research and still contains many relevant fossils, including more postcranial elements from a single adult specimen and, in particular, juvenile individuals, a particularly rare combination in this type of dinosaur. These discoveries are rapidly adding to the paleontological heritage of the province of Teruel, making it one of the prestigious regions for understanding the evolution of life on Earth.”
Scientists say the Riodeva fossil site continues to yield valuable material, including additional bones of the same adult dinosaur and rare juvenile remains. Discoveries like these are helping to establish Teruel as one of the most important places in the world to study prehistoric life and the evolution of dinosaurs.
published in study vertebrate zoology
Research has revealed vertebrate zoology Under the title “New insights into the phylogeny and skull evolution of stegosaurian dinosaurs: an extraordinary cranium from the European Late Jurassic (Dinosauria: Stegosauria).” The paper was written by paleontologists Sergio Sanchez Fenollosa and Alberto Cobos of the Fundación Dinopolis.
The project was supported by the Fundación Dinopolis, which is affiliated with the Medio Ambiente y Turismo Department of the Gobierno de Aragón. It is also part of the activities of the Research Group E04-23R FOCONTUR, funded by the Gobierno de Aragón through the Department of Amplio, Ciência y Universidades.
Additional support came from the Unidad de Paleontologia de Teruel, funded by the Gobierno de España through the Ministry of Ciência, Innovación y Universidades. Excavation work at the site also received support through the project Los Yacimientos Paleontologicos de la Provincia de Teruel como Factor de Desarrollo Territorial (IV)Jointly funded by the Gobierno de España and the Gobierno de Aragón through the Teruel Investment Fund through the Department of Presidencia, Economía y Justicia.