Paleontologists discovered dinosaur skull fragments within the Upper Jurassic Villard Alzobispo layer in Teruel, Spain, and confidently identified them as belonging to the species Centegosaurus dacentrurus armatus.
Skull of dacentrurus armatus from the Villard Alzobispo Formation in Teruel, Spain. Image credit: S. Sánchez-Fenollosa & A. Cobos, doi: 10.3897/vz.75.e146618.
The name Stegosauria was first introduced in 1877, with the initial reference to dacentrurus armatus occurring two years later.
Stegosauria constitutes a small clade of theropod dinosaurs, featuring iconic and recognizable representatives such as the genus Stegosaurus.
These dinosaurs were characterized by two rows of bony skin (plates and spines), extending principally from the neck to the tail’s edge.
Stegosaur fossils date from the Middle Jurassic through the Late Cretaceous, and they are generally represented by a limited number of partial skeletons worldwide.
Skull remains of stegosaurs are often fragmentary and infrequently found in the fossil record.
Nearly half of today’s scientifically recognized stegosaur species lack preserved skull material.
A recent study by Fundación Dinópolis paleontologists Sergio Sánchez Fenollosa and Alberto Cobos focused on the skull of dacentrurus armatus, a type of stegosaurus that roamed Europe approximately 150 million years ago.
Life reconstruction of dacentrurus armatus. Image credit: Sci.News.
“A comprehensive study of this extraordinary fossil has revealed anatomical features previously unknown in dacentrurus armatus, a typical European stegosaurus,” noted Dr. Sanchez Fenollosa.
“Dinosaur skulls are seldom preserved due to their extreme fragility.”
“This discovery is crucial for understanding the evolution of stegosaur skulls.”
Additionally, alongside detailed anatomical studies, we proposed a new hypothesis that redefines evolutionary relationships among stegosaurs worldwide.”
“This research has established a new grouping termed Neostegosauria.”
According to the team, Neostegosauria includes moderate to large stegosaur species that existed in Africa and Europe during the Middle to Late Jurassic, as well as Late Jurassic and Late Cretaceous Asia.
“This dual outcome represents both a remarkable fossil study and the proposal of new evolutionary theories, positioning our work as a key reference in stegosaur research,” remarked Dr. Cobos.
“The fossil site at Riodeva remains a subject of ongoing research and holds many related fossils, including additional postcranial elements from the same adult specimen, particularly rare combinations of this dinosaur type.”
“These findings are significantly enhancing the paleontological heritage of Teruel, making it a central region for understanding life’s evolution on Earth.”
The team’s research paper was published in the journal Vertebrate Zoology on May 26, 2025.
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S. Sánchez-Fenollosa & A. Cobos. 2025. New insights into the phylogeny and skull evolution of the stegosaur dinosaur: an extraordinary skull from the late Jurassic (Dinosaur: Stegosauria) in Europe. Vertebrate Zoology 75:165-189; doi:10.3897/vz.75.e146618
Source: www.sci.news
