Jiufotang Formation
The Jiufotang Formation is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms. It is a member of the Jehol group. The exact age of the Jiufotang has been debated for years, with estimates ranging from the Late Jurassic to the Early Cretaceous. New uranium-lead dates reveal the formation is deposited in the Aptian stage of the Early Cretaceous. Fossils of Microraptor and Jeholornis are from the Jiufotang.
Fossil content
Choristoderans
Fish
Mammaliamorphs
Several mammaliamorph specimens have been found from the Jiufotang, but only a few have been formally described and named.| Genus | Species | County | Member | Material | Notes |
| Cokotherium | C. jiufotangensis | Partial skeleton | A eutherian | ||
| Fossiomanus | F. sinensis | A nearly complete skeleton | A tritylodontid cynodont, likely the youngest known non-mammalian synapsid | ||
| Liaoconodon | L. hui | A nearly complete skeleton | A eutriconodont | ||
| Unnamed mammal | Unnamed | Partial remains including a foot and fragments of the skull | A mammal similar to Eomaia and Sinodelphys from the Yixian Formation. Found as stomach contents of Microraptor zhaoianus. |
Ornithischians
Pterosaurs
Saurischians
Skeletal and dental remains are known, the latter was assigned to an indeterminate titanosauriform.Enantiornithines
Euornithines
Non-ornithothoracean theropods
A large theropod tooth representing a distinct taxon from Sinotyrannus is known.| Genus | Species | County | Member | Material | Notes | Images |
| Chongmingia | C. zhengi | A partial skeleton with preserved soft tissues | A jinguofortisid avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | ||
Confuciusornis | C. sanctus | A primitive short-tailed avialan. Also present in the Yixian Formation | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Confuciusornis | C. jianchangensis | Liaoning | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
| Cratonavis | C. zhui | Jianchang | A complete skeleton with preserved feathers | A jinguofortisid avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |
Dalianraptor | D. cuhe | Nomen dubium, named from a forged artificially assembled specimen. | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Jeholornis | J. prima | A jeholornithiform avialan, also present in the Yixian Formation | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Jeholornis | J. palmapenis | A jeholornithiform avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Kompsornis | K. longicaudatus | "Nearly complete specimen". | A jeholornithiform avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | ||
Microraptor | M. gui | Shangheshou Bed | Extremely common | Could be synonym of Microraptor zhaoianus | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |
Microraptor | M. zhaoianus | Shangheshou Bed | "At least partial semiarticulated postcrania and several skulls." Feathered integument is also preserved. | A dromaeosaurid. | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |
Neimengornis | N. rectusmim | A jeholornithiform avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Omnivoropteryx | O. sinousaorum | An omnivoropterygiform avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Sapeornis | S. angustis | "Nearly complete skeleton without skull." | An omnivoropterygiform, a primitive short-tailed avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | ||
Sapeornis | S. chaoyangensis | An omnivoropterygiform, a primitive short-tailed avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Shenshiornis | Shenshiornis primita | An omnivoropterygiform avialan | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Similicaudipteryx | S. yixianensis | An oviraptorosaur | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
Sinotyrannus | S. kazuoensis | A tyrannosauroid | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis | |||
| Wulong | W. bohaiensis | Chaoyang, Liaoning | Complete articulated skeleton. | A dromaeosaurid | Image:Confuciusornis sanctus mmartyniuk.png|thumb|center|Confuciusornis sanctus Image:Jeholornis mmartyniuk wiki.jpg|thumb|center|Jeholornis prima Image:Sinotyrannus.png|thumb|center|Sinotyrannus kazuoensis |