Discover the most talked about and latest scientific content & concepts.

Concept: Cretaceous



Concepts: Continent, Pacific Ocean, Cretaceous, Antarctica, Sauropoda, Dinosaur, Titanosaur, Macronaria



Concepts: Extinction, Cretaceous, Dinosaur, Extinction event, Triassic, Jurassic, Archosaur, Norian



Concepts: Predation, Crypsis, Reptile, Mammal, Cretaceous, Dinosaur, Carnivore, Ankylosauria



Concepts: Nutrition, Extinction, Cretaceous, Fossil, Paleontology, Dinosaur, Carnivore, Late Cretaceous


This study reports on a new ceratopsid, Spiclypeus shipporum gen et sp. nov., from the lower Coal Ridge Member of the Judith River Formation in Montana, USA, which dates to ~76 Ma (upper Campanian). The species is distinguished by rugose dorsal contacts on the premaxillae for the nasals, laterally projecting postorbital horncores, fully fused and anteriorly curled P1 and P2 epiparietals, and a posterodorsally projecting P3 epiparietal. The holotype specimen is also notable for its pathological left squamosal and humerus, which show varied signs of osteomyelitis and osteoarthritis. Although the postorbital horncores of Spiclypeus closely resemble those of the contemporaneous ‘Ceratops’, the horncores of both genera are nevertheless indistinguishable from those of some other horned dinosaurs, including Albertaceratops and Kosmoceratops; ‘Ceratops’ is therefore maintained as a nomen dubium. Cladistic analysis recovers Spiclypeus as the sister taxon to the clade Vagaceratops + Kosmoceratops, and appears transitional in the morphology of its epiparietals. The discovery of Spiclypeus adds to the poorly known dinosaur fauna of the Judith River Formation, and suggests faunal turnover within the formation.

Concepts: Cladistics, Clade, Cretaceous, Dinosaur, Taxon, Linnaean taxonomy, Ceratopsidae, Nomen dubium


Pterosaurs were the first vertebrates to evolve powered flight and the largest animals to ever take wing. The pterosaurs persisted for over 150 million years before disappearing at the end of the Cretaceous, but the patterns of and processes driving their extinction remain unclear. Only a single family, Azhdarchidae, is definitively known from the late Maastrichtian, suggesting a gradual decline in diversity in the Late Cretaceous, with the Cretaceous-Paleogene (K-Pg) extinction eliminating a few late-surviving species. However, this apparent pattern may simply reflect poor sampling of fossils. Here, we describe a diverse pterosaur assemblage from the late Maastrichtian of Morocco that includes not only Azhdarchidae but the youngest known Pteranodontidae and Nyctosauridae. With 3 families and at least 7 species present, the assemblage represents the most diverse known Late Cretaceous pterosaur assemblage and dramatically increases the diversity of Maastrichtian pterosaurs. At least 3 families-Pteranodontidae, Nyctosauridae, and Azhdarchidae-persisted into the late Maastrichtian. Late Maastrichtian pterosaurs show increased niche occupation relative to earlier, Santonian-Campanian faunas and successfully outcompeted birds at large sizes. These patterns suggest an abrupt mass extinction of pterosaurs at the K-Pg boundary.

Concepts: Mammal, Cretaceous, Pterosaur, Pterodactyloidea, Dinosaur, Cretaceous–Tertiary extinction event, Late Cretaceous, Pteranodon



Concepts: Bird, Cretaceous, Dinosaur, Saurischia, Theropoda, Ceratosauria, Late Cretaceous, Carnosauria



Concepts: United States, Phylogenetics, Cladistics, North America, Cretaceous, Fossil, Dinosaur, Ceratopsidae



Concepts: Skull, Cretaceous, Dinosaur, Saurischia, Theropoda, Maniraptora, Oviraptorosauria, Oviraptoridae



Concepts: Europe, Pelvis, Acetabulum, Cretaceous, Pterosaur, Pterodactyloidea, Western Europe, Ilium