Corythoraptor

Discovery and Naming

Corythoraptor was described in 2017 by Chinese palaeontologist Lü Junchang and colleagues, based on a nearly complete adult skeleton discovered in the Late Cretaceous Nanxiong Formation near Ganzhou Railway Station in Jiangxi, South China. The specimen, now housed at the Jinzhou Palaeontological Museum, preserves the skull, lower jaw, and most of the body, making it one of the better-preserved oviraptorosaur fossils. The genus name refers to its prominent crest, while the species name honours American palaeontologist Louis L. Jacobs.

Physical Description

Size and Growth

The holotype specimen represents a young adult about 1.6 m long and weighing between 33 - 40 kg . Bone growth patterns indicate it was still maturing at the time of death, so fully grown individuals may have been closer to 2 m. Despite its light build, Corythoraptor's combination of a strong beak, agile frame, and distinctive crest would have made it a striking sight in its Late Cretaceous habitat.

Evidence of Feathers

Although no direct feather impressions have been found with Corythoraptor, strong evidence from related oviraptorosaurs such as Caudipteryx and Protarchaeopteryx suggests it was feathered. These relatives preserve well-developed feathers on the arms and tail, features likely used for both insulation and display. Many oviraptorosaurs also had a pygostyle-like structure at the tail tip, which in living birds supports a fan of feathers, and fossils show arm positions consistent with brooding eggs beneath feathered wings. Given these similarities, Corythoraptor almost certainly had a similar feather covering, with small wings and a tail fan.

Diet and Feeding Habits

The exact diet of Corythoraptor is unknown, but it was probably omnivorous. Jaw similarities to herbivores such as parrots and tortoises, along with the presence of gastroliths ("stomach stones") in close relatives, suggest that plant matter, including drought-tolerant vegetation, nuts, and seeds, was a significant part of its diet. These gastroliths would have helped grind up tough food, much like the gizzard of modern birds. While shellfish have been suggested as another food source, the beak does not seem well-suited for crushing hard shells, and such prey was likely rare in its arid environment. In the Nanxiong Formation, Corythoraptor lived alongside six other oviraptorosaurs, so it may have specialised in certain foods to avoid competition, a behaviour known as niche partitioning.

Egg Thieves?

When oviraptorids were first discovered, they were thought to be specialised egg thieves - hence their name, which means "egg thief lizard." This idea originated in the 1920s when a specimen of Oviraptor (an oviraptorid dinosaur from Mongolia) was found atop a nest of eggs believed to belong to Protoceratops (a small plant-eating dinosaur). Later discoveries in the 1990s, including fossils of Citipati (another oviraptorid) preserved in clear brooding positions and a Citipati embryo inside such eggs, showed that these nests belonged to the oviraptorids themselves. While they may have occasionally eaten eggs opportunistically, their beaks were better suited for shearing plant material than for crushing shells.

Environment

Corythoraptor lived in what is now the Nanxiong Formation of southern China, part of the fossil-rich "Ganzhou Dinosaurian Fauna." This area is notable for its exceptional diversity of oviraptorids, including Banji, Jiangxisaurus, Nankangia, Ganzhousaurus, Huanansaurus, and Tongtianlong. Other dinosaurs in the region included the long-necked Gannansaurus, the tyrannosaurid Qianzhousaurus, and the therizinosaurid Nanshiungosaurus. Fossil evidence suggests a lakeside environment, though the prevalence of drought-tolerant plants in oviraptorid diets indicates that the climate at the time may have been arid or semi-arid.

Is Corythoraptor Related to Other ‘Raptors'?

Despite its name, Corythoraptor was not especially close to the famous "raptors" like Velociraptor. Both belonged to the broader group of theropod dinosaurs, but Velociraptor was a dromaeosaur - a predatory, sickle-clawed hunter - while Corythoraptor was an oviraptorid, a mainly plant- and seed-eating group with toothless beaks and often elaborate head crests. The "raptor" part of Corythoraptor's name refers to its bird-like build and grasping claws, not a close family relationship with Velociraptor.