About Heyuannia (formerly Ajancingenia)
*According to the latest research, the skull of this exhibited specimen belongs to a different genus (Conchoraptor).
Did you know a dinosaur that used to be listed in encyclopedias under the names "Ingenia" or "Ajancingenia"? In fact, this dinosaur has had a strange fate, with its name changing many times over the course of its research history.
When it was first discovered in the Gobi Desert of Mongolia in 1981, it was named "Ingenia" after the discovery site. However, it was later discovered that this name was already being used as the name of a nematode (a small parasitic worm). Because there is a rule that a scientific name for a living organism must be unique in the world, the dinosaur's name Ingenia became invalid.
Then, in 2013, a new name, "Ajancingenia (meaning traveler)", was proposed. However, the paper proposing this name contained major research misconduct, such as using other researchers' data without permission and tracing and flipping their illustrations, drawing fierce criticism from researchers around the world.
Finally, in 2018, an investigation by a Canadian research team proved that this dinosaur is a very close relative (the same genus) to "Heyuannia," a dinosaur discovered in China. Currently, it has been integrated into the scientific name "Heyuannia yanshini," resolving the long-standing confusion over its name.
| Period | Scientific Name (Genus) | History and Reasons for Name Change |
|---|---|---|
| 1981 - | Ingenia | Named after the discovery site, but later invalidated because the name was already preoccupied by an existing nematode genus. |
| 2013 - | Ajancingenia | Proposed as a replacement name, but faced severe criticism due to research misconduct in the published paper, including the unauthorized use of data and traced figures. |
| 2018 - Present | Heyuannia | Latest research proved it belongs to the same genus as Heyuannia discovered in China, integrating it as Heyuannia yanshini. |
| Scientific Name (Genus) | Heyuannia |
| Meaning of Name |
"Of Heyuan (discovery site in China)" *Old name Ajancingenia means "traveler" |
| Classification | Saurischia, Theropoda, Oviraptorosauria, Oviraptoridae, Heyuanniinae |
| Total Length | About 1.4 - 1.5m |
| Weight | About 20kg |
| Diet | Omnivorous (hard plant roots, shellfish, insects, eggs of other species, etc.) |
| Period | Late Cretaceous (about 72.1 to 70 million years ago) |
| Sub-classification / Species Name | Heyuannia yanshini |
| Old Classification / Species Name | Ajancingenia yanshini / Ingenia yanshini |
| Paper of Name Integration | Funston, G.F., et al. 2018. "Oviraptorosaur anatomy, diversity and ecology in the Nemegt Basin" |
[Latest Research] The Truth About the "Chimera Specimen" Revealed
For many years, it has been depicted in dinosaur encyclopedias and museums with "a small crest on its head, or a round skull without a crest." However, a shocking fact that shook the paleontological world was revealed in a recent paper published by an American research team in 2025.
The "full body skeleton with a skull" that had been considered the standard for this dinosaur for the past 40 years was actually a "chimera specimen" made by artificially attaching the fossil of another dinosaur.
Specifically, the skull of "Conchoraptor," a completely different dinosaur that lived in the same area, was forcibly attached to the body and limb bones of Heyuannia yanshini.
What is a chimera specimen?
Named after the "Chimera," a monster from Greek mythology with the head of a lion, the body of a goat, and the tail of a snake, it refers to a specimen in which fossils of multiple different organisms are mixed and assembled into one. In addition to intentional forgery, there are cases where different fossils are found close together at an excavation site and mistakenly assembled thinking they are the same species.
With this discovery, the latest and correct information is that "a definitive complete skull of Heyuannia yanshini has not been found yet." It is hoped that a real skull will be discovered in the Gobi Desert in the future.
Characteristics and Ecology of Heyuannia
*The shape of the head is based on the theory at the time (chimera specimen).
Heyuannia yanshini had a bird-like appearance with its entire body covered in feathers. Mongolia at the time was a semi-arid region with vast sand dunes. To survive in such a harsh environment, they underwent a very unique evolution.
Its most striking feature is its extremely short and very robust forelimbs (arms). In particular, the claw on its first digit (thumb) was more than twice the size of its second digit (index finger), and the bone was thick and powerful.
While other dinosaurs living in the same era and place had thin arms, it is thought that Heyuannia yanshini used these strong arms and huge claws to dig through dry, hard soil to find nutritious roots (tubers) and insects underground, or to hold down and break open shells and eggs of other dinosaurs to eat.
In addition, an examination of their tail skeleton revealed that they had developed muscles to powerfully pull their hind legs. It is speculated that they had strong leg power, while simultaneously spreading their magnificent fan-shaped tail feathers to use them for communication (display behavior) with their peers.
Blue-green Eggs and Dinosaur "Parenting"
There was also a major discovery regarding the color of eggshells from fossils of their relatives (genus Heyuannia). As a result of analyzing the components left in the fossil shells using state-of-the-art technology, it was found that their eggs were a vivid "blue-green" like those of modern robins and emus.
What the color of the eggs tells us
When eggs are completely buried in the soil, like those of crocodiles and turtles, there is no point in coloring them. Being blue-green is definitive evidence that they did not bury their eggs in the soil, but laid them in an "open nest" on the ground. The color is thought to have served as camouflage to blend in with surrounding vegetation.
Furthermore, fossils have also been found showing the parent dinosaur sitting in the middle of eggs beautifully arranged in a ring, spreading its feathers to warm and protect the eggs from predators (incubating). The behavior of birds warming eggs and raising their young had already begun in the "age of dinosaurs" long before birds learned to fly.
Let's Go See Heyuannia yanshini (formerly Ajancingenia)
Fossils of Heyuannia yanshini (formerly Ajancingenia, Ingenia) can be seen at the following museum.
However, please note that the exhibits may have changed. Please check the latest information yourself.
Institute of Paleontology, Mongolian Academy of Sciences (Ulaanbaatar, Mongolia)
Fossil parts available: Real fossils, full body reconstructed skeleton
Highlights: This facility can be said to be the "home base" of Heyuannia yanshini. It houses and exhibits many precious real fossils excavated from the Gobi Desert, including the holotype specimen (the standard specimen defining the species). It boasts one of the world's leading oviraptorid collections.
Heyuannia yanshini was formerly known as "Ingenia" or "Ajancingenia." In many museums, both the old and new names are listed together, or they may be exhibited under the old name, so please look for the old name as well when visiting.
Fossil Gallery
