A fossil animal can be known for decades while one of its most distinctive features remains missing. The giraffid originally named Palaeotragus tungurensis in 1936 was represented by teeth, jaws and a partial skull from Inner Mongolia. But its ossicones—the head appendages so informative in the giraffe family—were unknown.
A nearly complete isolated ossicone collected in 2011 changed that comparison. Xiaoming Wang, Nikos Solounias, Su-kuan Hou, Lu Li and Yukimitsu Tomida described it in a 2025 PLOS ONE paper. They proposed a new genus, Qilin, for the previously named species and placed it within a group of early giraffine relatives called Bohlinini.
The study’s interest lies in how one well-preserved bone can sharpen a classification—and in the specific association that still needs a better fossil to confirm.
A shape preserved from several directions
The ossicone came from the Tunggur Formation. Correlation with a neighbouring dated rock sequence placed the relevant deposits roughly between 11.7 and 12.8 million years ago. That age depends on the geological correlation; it is not a direct date obtained from the ossicone itself.
The researchers used laser scanning to produce an accurate surface model and microCT to inspect the interior. Virtual cross-sections let them follow changes in shape along the shaft without cutting the fossil.
Several features stood out. Viewed from the side, the shaft was unusually upright. Its rounded tip expanded slightly above a narrower region, while the base carried a broad, plate-like flange with bumpy secondary growth. Cross-sections changed from more rounded near the top to more flattened towards the base.
Those details distinguished the specimen from a generic “horn.” Position, curvature, surface growth and the relation between shaft and base are separate anatomical clues. Their combination is what makes a fossil useful for comparing evolutionary relationships.
Was the flange part of one ossicone or a second one?
Some extinct giraffids carried two pairs of ossicones, and closely placed appendages could become fused at their bases. The broad flange therefore raised a concrete question: was this one ossicone with additional growth, or a large and small appendage joined together?
Wang and colleagues favoured the first interpretation. They considered the flange more plate-like than the rounded or conical form expected of a separate small ossicone. They did not find a clear boundary separating it from the main shaft.
The comparison was not conclusive. The bone had detached from its skull, leaving its precise orientation unresolved. Even whether it belonged on the left or right side could not be settled securely. The paper discussed alternative interpretations and treated the single-pair reconstruction as the preferred hypothesis.
Its underside also suggested a young individual whose ossicone had not yet fused to the skull. A juvenile’s anatomy can differ from an adult’s, so interpreting the unusual basal growth requires both developmental and evolutionary comparisons.
A new name depended on combining old and new evidence
The researchers compared the ossicone with previously collected dental and limb material assigned to the Tunggur animal. Certain folds on the upper premolars bent strongly inward, resembling those of Bohlinia. Referred limb material also showed an elongated, slender form and a groove that helped place it within the proposed group.
Together with the new ossicone, those features supported removing the animal from Palaeotragus and giving it the genus name Qilin. The name applies to a newly distinguished genus, not a claim that the species itself had never been described.
The crucial condition is that the isolated elements belong to the same kind of animal. More than one giraffid may be represented in the older Tunggur collections, and the new ossicone was not attached to a skull carrying diagnostic teeth. The authors acknowledged that uncertainty while arguing that its shape fitted Qilin better than the alternative.
The resulting hypothesis is more useful because the uncertain step can be stated precisely. A skull preserving both the ossicone attachment and the relevant teeth would test the proposed association directly.
The neck is still missing
The authors placed Qilin near early members of a broader giraffine history that includes living giraffes. They did not recover its cervical vertebrae. A relatively long neck was inferred from limb proportions and relationships, not demonstrated by an assembled fossil neck.
That is a meaningful contrast with Danowitz and colleagues’ study of Samotherium, where a nearly complete cervical series allowed individual neck features to be compared with giraffe and okapi. The Qilin study can speak in greater detail about headgear than about the neck beneath it.
For readers following giraffe neck evolution, the distinction prevents a reconstruction from becoming stronger evidence than the bones available. The new ossicone adds an important part of the animal, while leaving others open.
The next decisive discovery need not be another spectacular isolated appendage. Associated skull, tooth and limb material would connect the existing clues; cervical vertebrae would independently test the proposed neck proportions. Wang and colleagues made those missing connections easier to define by documenting the ossicone in enough detail to compare, reconstruct and question it.
Sources
Xiaoming Wang, Nikos Solounias, Su-kuan Hou, Lu Li, Yukimitsu Tomida (2025). A new giraffe ossicone from Wolf Camp, Tunggur Formation, Inner Mongolia suggests a new genus in Bohlinini (Artiodactyla, Giraffidae). PLOS One. DOI: 10.1371/journal.pone.0328405. Read the full paper.
