A new genus and species of stegosaur from the Middle Jurassic period has been identified from fossilized posterior skulls discovered in the Middle Atlas Mountains, south of Fez, Morocco.
Tireosaurus atlasix lived in North Africa during the middle Jurassic period, about 165 million years ago.
This species is closely related to Dakentrulus members of the clade Dacenturinae within the Tyreophoran dinosaur family Stegosauridae.
Dr. Mostafa Oukas of Casablanca’s Universidad Hassan II and his colleagues said, “Thireophora is a diverse clade of herbivorous ornithischians consisting of stegosaurs, sclerosaurs, and basal types.”
“Thyleophorans have an extensive fossil record spanning from the Early Jurassic to the Late Cretaceous and are best known from well-preserved specimens from Laurasia.”
“In contrast, fossil remains are poorly known in Gondwana, and most of them are partial,” the researchers added.
“In Africa, thyreophorans may have been present since the Early Middle Jurassic.”
“Stegosaur body fossils have been recorded from the Middle Jurassic of Morocco, the Late Jurassic of Tanzania, and the Early Cretaceous of South Africa.”
“African ankylosaurs are represented by Spicomerus afar from Morocco during the Middle Jurassic period.”
divided partial skeleton Tireosaurus atlasix found in gray marl. El Mars III formation is located in the northern part of the Bourafa region near Bourmane, in the Atlas region of central Morocco.
“In 2021, during a geological mapping mission south of Bourmane, we discovered a new site rich in dinosaur remains in the El Mars III Formation,” the paleontologists said.
“This site, named Bourafa North, is located north of the Bourafa quarry.”
“This material was collected during several consecutive field trips and consists of the posterior skull of a stegosaur, including dorsal vertebrae and ribs, limb bones, and skin armor.”
According to the team: Tireosaurus atlasix had a strange asymmetrical skin armor, unique among stegosaurs.
“Dermal armor is Tireosaurus atlasix “It is composed of up to 4 cm (1.6 in) thick bone oval to subrectangular shaped osteoderms,” the researchers said.
“The asymmetrical texture of the sides, with one side roughly decorated with small holes and strands of fibers and the other with a distinct cross-hatch pattern, is unlike anything previously observed in other stegosaurs and sclerosaurs. It’s clearly different.”
“The bone histology of these osteoderms is reminiscent of the histology of stegosaur tail spines.”
“These osteoderms are interpreted to have been placed in a lying position on the animal’s body, rather than in an upright position.”
Tireosaurus atlasix was estimated to be over 6 meters (19.7 feet) long.
“The axial features indicate that this specimen belongs to a medium- to large-sized stegosaur,” the scientists said.
“The holotype corresponds to an adult individual that has not yet reached its maximum body size.”
discovery of Tireosaurus atlasix is important in understanding the evolutionary history of stegosaurs and other thyreophora dinosaurs.
“Recent discoveries are adraticrit and Tireosaurus atlasix “We provide insight into the early evolution of stegosaurs during the Middle Jurassic of Africa,” the authors concluded.
of findings appear in the diary Gondwana research.
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Omar Zafati other. 2024. A new stegosaur dinosaur (Ornithischian: Thyreophora) with prominent cutaneous armor that lived during the Middle Jurassic period of North Africa. Gondwana research 131: 344-362; doi: 10.1016/j.gr.2024.03.009
Source: www.sci.news
