Prenoceratops, (meaning 'bent or prone-horned face' and derived from Greek prene-/πρηνη- meaning 'bent forwards' or 'prone', cerat-/κερατ- meaning 'horn' and -ops/ωψ meaning 'face') is a genus of herbivorous ceratopsian dinosaur from the Late Cretaceous Period. It was a relatively small dinosaur, reaching 1.3 m (4.3 ft) in length and 20 kg (44 lb) in body mass.[1] Its fossils have been found in the upper Two Medicine Formation in the present-day U.S. state of Montana, in Campanian age rock layers that have been dated to 74.3 million years ago.[2] Fossils were also found in the Oldman Formation in the modern day Canadian province of Alberta, dating to around 77 million years ago.[3][4]
Prenoceratops was first discovered on a Blackfeet reservation in Pondera County, Montana in layers coming from the Campanian Two Medicine Formation.[5] The locality at which Prenoceratops was found was filled with many disassociated fossil elements of many individuals, known as a bonebed, though only the skull material has been described as of 2022.[2][5] The holotype was one of the few associated specimens, including a surrangular fused with an articular, the specimen is designated as TCM 2003.1.1. Prenoceratops was later described by Brenda J. Chinnery in 2004, though the taxon has been little noticed since.[5] It is unusual in that it is the only basal neoceratopsian known from a bonebed and the sheer number of elements.[2][5]
An isolated right frontal from the Oldman Formation of southern Alberta, Canada was described in 2010 and ascribed to Prenoceratops as P. sp.[3] The fossil was found near a fossilized nesting site of Hypacrosaurus.[3]
Prenoceratops belonged to the Ceratopsia (which name is derived from Ancient Greek, meaning 'horned face'), a group of herbivorous dinosaurs with parrot-like beaks, which thrived in North America and Asia during the Cretaceous Period. It is closely related to Leptoceratops, which it antedates by several million years. It is characterized by a lower, more sloping head than that of Leptoceratops.
Prenoceratops, like all ceratopsians, was a herbivore. During the Cretaceous, flowering plants were "geographically limited on the landscape", and so it is likely that this dinosaur fed on the predominant plants of the era: ferns, cycads and conifers. It would have used its sharp ceratopsian beak to bite off the leaves or needles.