| Diet | Herbivore |
| Height | Unknown - estimated 4-6m |
| Length | Unknown - estimated 15-20m |
| Weight | 10 tonnes |
| Environment | Land |
| Era | Cretaceous |
| Period | Early Cretaceous |
| Type | Sauropod |
| Location | China And Possibly South Korea |
Chiayusaurus is one of the more mysterious sauropod dinosaurs, known only from fragmentary teeth discovered in China and possibly South Korea. This obscure dinosaur lived during the Early to Late Cretaceous period, between approximately 149 and 84 million years ago. The name originally appeared as Chiayüsaurus in scientific literature, but was later corrected to Chiayusaurus as the International Code of Zoological Nomenclature doesn't permit special characters in scientific names.
As a sauropod, Chiayusaurus would have been a massive, long-necked herbivore that walked on four legs. Like other members of this group, it would have used its elongated neck to reach vegetation at various heights, from ground-level ferns to tall conifer trees. The teeth that have been found suggest it was well-adapted for processing plant material, though the exact feeding strategy remains unclear due to the limited fossil evidence.
Two species were originally named for this genus, but only the type species C. lacustris is still considered potentially valid by most palaeontologists. The fragmentary nature of the remains makes it extremely difficult to determine Chiayusaurus's exact relationships to other sauropods or to provide detailed information about its anatomy and behaviour.
The discovery of Chiayusaurus teeth in both China and possibly South Korea suggests this sauropod may have had a relatively wide geographical range across East Asia during the Cretaceous period, though more complete remains would be needed to confirm this distribution.
Known only from teeth, so distinguishing features are largely unknown. The teeth appear to be typical of sauropod dinosaurs, adapted for processing plant material, but lack diagnostic features that would clearly separate Chiayusaurus from other sauropods.
Behaviour can only be inferred from its classification as a sauropod. Chiayusaurus would likely have been a slow-moving browser, using its presumably long neck to feed on vegetation at various heights. Like other sauropods, it may have lived in herds for protection from predators.
Chiayusaurus was first described by Yang Zhongjian (C.C. Young) in 1949. The original fossils were discovered at Jiayu County, Hubei Province, China.
