Pulaosaurus qinglong

We're admittedly getting to Pulaosaurus qinglong a bit after announcement and description, but what's a few weeks after 160 million years? "Hypsil"-type dinosaurs are always going to be welcome here, and this one also has potential gut contents, albeit left for a later date, so let's extend a welcome and have a look after the jump break.

Genus and Species: Pulaosaurus qinglong. "Pulao" is a type of small dragon in Chinese mythology noted for making loud noises, and its use here refers to the dinosaur possibly producing bird-like noises. "Qinglong" is the county in Hebei Province where the type specimen was found (Yang et al. 2025). This gives us something like "Pulao lizard from Qinglong".

Citation: Yang, Y., J. L. King, and Xu X. 2025. A new neornithischian dinosaur from the Upper Jurassic Tiaojishan Formation of northern China. PeerJ 13:e19664. doi: http://doi.org/10.7717/peerj.19664

Geography and Stratigraphy: P. qinglong comes from rocks of the lower Upper Jurassic Tiaojishan Formation (Oxfordian) in southern Shimen Gou, Qinglong County, Hebei, China (Yang et al. 2025).

Holotype: The type and only known specimen is IVPP V30936 (Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China). It is a largely complete and articulated specimen, although a bit smooshed around the skull and shoulders. Based on the size of the eye socket and the presence of unfused sutures in the neck and back vertebrae, the type individual was likely immature (Yang et al. 2025).

If you know your "hypsil"-type dinosaurs, you'll know the basic form without looking; for all their charms, this kind of dinosaur had a particular shape and stuck to it through thick and thin. There's a triangular skull, a few premaxillary teeth at the tip of the snout (five per side in this case), a short neck, a long tail, ossified tendons (confined to the back rather than the tail in this case; maybe they just hadn't ossified yet), a shortish arm with five not particularly long fingers, tibia longer than femur, and functionally tridactyl feet. It's your basic small herbivorous bipedal ornithischian dinosaur, built for speed. A phylogenetic analysis found P. qinglong at the base of Neornithischia, with neighbors such as Agilisaurus louderbacki and Hexinlusaurus multidens (Yang et al. 2025), which is about where one would expect it to show up.

But go ahead and look anyway; it's a quality specimen. Figure 1 in Yang et al. (2025). CC BY 4.0.

P. qinglong is unusual in preserving structural elements of the throat, including arytenoids and possible ceratobranchials. For a bit of background, the hyolaryngeal apparatus of an archosaur consists of nine or more not especially large or robust elements that are largely cartilaginous and are not anchored to any other hard structures. They are involved with functions such as supporting the tongue, swallowing, breathing, and vocalizing. Just to increase the challenge of identification, humans get by with just one element in the throat, the hyoid bone. Between the poor preservation potential and unfamiliarity, it's not surprising that we don't have a great record for these elements in classic dinosaurs. Ceratobranchials turn up from time to time, but the other elements have only be identified in a handful of finds. P. qinglong's holotype represents the second instance of an ossified laryngeal apparatus, akin to a bird (the other being in Pinacosaurus grangeri [Yoshida et al. 2023]). Yang et al. (2025) interpret this as evidence of widely distributed bony hyolaryngeal apparatuses in dinosaurs. One may ask where the elements are in other dinosaurs if this is true. Yang et al. note the potential difficulty in preservation, and also suggest that some records of certatobranchials may be misidentified examples of the other elements. They also note that the arytenoids of P. qinglong are relatively longer than those in Pinacosaurus, suggesting their new species had better vocal capabilities (and suggesting the genus name).

The preserved hyolarygeal elements of P. qinglong; Figure 5 in Yang et al. (2025). Abbreviations are: "ap, arytenoid process; c, ceratobranchial; lw, laterodorsal wings of the arytenoids; mw, mediodorsal wings of the arytenoids." CC BY 4.0.

There are also small impressions of varying ovoid or elliptical shape, 3 to 8 mm (0.1 to 0.3 in) in diameter, found in the body cavity. Yang et al. interpreted them as potential gut contents, possibly seeds, but left them to be more fully described at a later date (so I suppose we'll have another post on P. qinglong in the future).

Termination of digestion? Stuff that just happened to be here? Or something else? Tune in later to find out! "P-Pebbles; I-Impressions of possible plant seeds." Figure 16 in Yang et al. (2025). CC BY 4.0.

References

Yang, Y., J. L. King, and Xu X. 2025. A new neornithischian dinosaur from the Upper Jurassic Tiaojishan Formation of northern China. PeerJ 13: e19664. doi: http://doi.org/10.7717/peerj.19664

Yoshida, J., Y. Kobayashi, and M. A. Norell. 2023. An ankylosaur larynx provides insights for bird-like vocalization in non-avian dinosaurs. Communications Biology 6(1): 152. doi: https://doi.org/10.1038/s42003-023-04513-x