Stegosaurs, known for their distinctive plates and spikes, were herbivorous dinosaurs that roamed the Earth on four legs. A groundbreaking fossil, recently unearthed by Fundación Dinópolis at the "Están de Colón" site in the Villar del Arzobispo Formation, sheds new light on these fascinating creatures from the Late Jurassic period.
This specimen has been classified as Dacentrurus armatus, a prominent stegosaur species in Europe. It is hailed as the most well-preserved stegosaur skull ever found on the continent, a significant feat given the fragility of dinosaur skulls, which seldom endure intact over millions of years.
Sergio Sánchez Fenollosa, a researcher at Fundación Dinópolis and co-author of the study, remarked, "The meticulous examination of this exceptional fossil has unveiled previously unrecognized anatomical features of Dacentrurus armatus, marking 150 years since its initial description in 2025. The rarity of preserved dinosaur skulls makes this discovery pivotal for understanding the evolution of stegosaurian skulls."
In addition to anatomical insights, the research proposes a new evolutionary framework that redefines the relationships among stegosaurs globally. This has led to the establishment of a new group termed Neostegosauria.
Innovative Dinosaur Evolution Framework
The Neostegosauria group encompasses medium and large stegosaur species that thrived on multiple continents during various periods of the Jurassic and Early Cretaceous. The findings indicate that members of this group inhabited regions now known as Africa and Europe during the Middle and Late Jurassic, North America in the Late Jurassic, and parts of Asia in the Late Jurassic and Early Cretaceous.
The research team believes this new classification could significantly alter the scientific community's perception of the evolutionary history and geographical spread of plated dinosaurs.
Fossil Site Continues to Yield Significant Discoveries
Alberto Cobos, managing director of Fundación Dinópolis and co-author of the study, highlighted the broader implications of this find: "This dual achievement--both the study of a remarkable fossil and the introduction of a new evolutionary hypothesis--positions our research as a pivotal reference in stegosaur studies."
The Riodeva fossil site remains a treasure trove for paleontological research, with ongoing excavations revealing numerous relevant fossils, including additional bones from the same adult specimen and rare juvenile remains. Such discoveries enhance the paleontological legacy of Teruel, establishing it as a key region for understanding the evolution of life on our planet.
Published Insights in Vertebrate Zoology
The findings have been documented in 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 work was conducted by paleontologists Sergio Sánchez Fenollosa and Alberto Cobos from Fundación Dinópolis.
This project received support from various institutions, including the Dept. of Medio Ambiente y Turismo of the Gobierno de Aragón, and the Unidad de Paleontología de Teruel, funded by the Gobierno de España.