Jiufotang Formation

The Jiufotang Formation (Chinese: 九佛堂组; pinyin: jiǔfótáng zǔ) is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms (see Jehol Biota). 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.^[2] Fossils of Microraptor and Jeholornis are from the Jiufotang.^[3]

Jiufotang Formation
Stratigraphic range: Aptian ~122–118.9 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Jehol Group
Sub-units	Shangheshou & Meileyingzi Beds
Underlies	Fuxin & Shahai Formations
Overlies	Yixian Formation
Lithology
Primary	Mudstone
Other	Sandstone
Location
Coordinates	41.2°N 119.4°E / 41.2; 119.4
Approximate paleocoordinates	44.4°N 119.5°E / 44.4; 119.5
Region	Liaoning
Country	China
Type section
Named for	Jiufotang, Pingfangzi, Liaoning
Named by	Ryuji Endo
Year defined	1934[1]
Jiufotang Formation (China) Show map of China Jiufotang Formation (Liaoning) Show map of Liaoning

Fossil content

Choristoderans

Genus	Species	County	Member	Abundance	Notes
Philydrosaurus	P. proseilus				Monjurosuchid
Ikechosaurus	I. pijiagouensis				Simoedosaurid
Liaoxisaurus	L. chaoyangensis				Simoedosaurid
Hyphalosaurus	H. baitaigouensis[4]				Hyphalosaurid

Fish

Genus	Species	County	Member	Notes	Images
Caeruleum	C. miraculum[5]	Weichang		A lamprey
	C. gracilis[6]	Weichang		A lamprey
Hebeimyzon[7]	H. weichangensis	Weichang		A lamprey
Jinanichthys	J. longicephalus			An osteoglossomorph
Lycoptera	L. davidi			An osteoglossomorph
Peipiaosteus	P. pani			A fish related to sturgeons
Protopsephurus	P. liui			A paddlefish
Sinamia	S. zdanskyi			An amiiform

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[8]			Partial skeleton	A eutherian
Fossiomanus	F. sinensis[9]			A nearly complete skeleton	A tritylodontid cynodont, likely the youngest known non-mammalian synapsid
Liaoconodon	L. hui[10]			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

Genus	Species	Locality	County	Member	Material	Notes	Images
Chuanqilong[11]	C. chaoyangensis[11]		Liaoning		A nearly complete skeleton missing only the distal portion of the caudal series.	A basal ankylosaurid, sister taxon to Liaoningosaurus.[11]	Liaoningosaurus paradoxus Psittacosaurus meileyingensis Psittacosaurus mongoliensis
Liaoningosaurus[12]	L. paradoxus[12]	Baicaigou locality	Liaoning		A nearly complete, articulated skeleton	A basal ankylosaurid.
Psittacosaurus	P. meileyingensis			Meileyingzi Bed	"[Four] individuals, [two] complete skulls."[13]	A ceratopsian.
	P. mongoliensis			Shangheshou and Meileyingzi Beds

Pterosaurs

Genus	Species	County	Member	Material	Notes	Images
Chaoyangopterus	C. zhangi				A chaoyangopterid[14]	Feilongus Liaoningopterus Meilifeilong Nemicolopterus Nurhachius Sinopterus and Huaxiadraco Vesperopterylus
Eoazhdarcho	E. liaoxiensis				A chaoyangopterid[14]
Feilongus	F. youngi		Jianshangou Bed		A boreopterid
Forfexopterus	F. jeholensis				A ctenochasmatid
Gladocephaloideus	G. jingangshanensis		Jingangshan Bed		A ctenochasmatid
Guidraco	G. venator				A pteranodontoid[15]
Hongshanopterus	H. lacustris				An istiodactylid
Huaxiadraco	H. corollatus			Multiple specimens	A tapejarid[16]
"Huaxiapterus"	"H." benxiensis				A tapejarid; synonymized with Huaxiadraco in 2023
Ikrandraco	I. avatar				A pteranodontoid[15]
Jidapterus	J. edentus				A chaoyangopterid[14]
Liaoningopterus	L. gui				A pteranodontoid[15]
Liaoxipterus	L. brachyognathus				An istiodactylid[14]
Linlongopterus	L. jennyae				A pteranodontoid[15]
Meilifeilong	M. youhao	Jianchang		A nearly complete skeleton and a partial skull	A chaoyangopterid[17]
Nemicolopterus	N. crypticus				A tapejaromorph; previously and still occasionally thought to be a tapejarid. Most likely a juvenile, hence small size.
Nurhachius	N. ignaciobritoi				An istiodactylid[14]
Pangupterus	P. liui				A pterodactyloid
Shenzhoupterus	S. chaoyangensis				A chaoyangopterid
	S. sanyainus				A chaoyangopterid[18]
Sinopterus	S. dongi				A tapejarid[14]
	S. jii				Previously known as Huxiapterus jii
Vesperopterylus	V. lamadongensis				An anurognathid

Saurischians

Skeletal^[19] and dental^[20] remains are known, the latter was assigned to an indeterminate titanosauriform.

Enantiornithines

Genus	Species	County	Member	Material	Notes	Images
Alethoalaornis	A. agitornis[21]				An enantiornithean	Brevirostruavis Cuspirostrisornis Longipteryx Rapaxavis Sinornis Yuanchuavis
Boluochia	B. zhengi			"Partial skull [and] partial postcranium."[22]	A longipterygid
Brevirostruavis	B. macrohyoideus			"an extremely elongate bony hyoid element (only slightly shorter than the skull), combined with a short cranial rostrum."[23]	An enantiornithine
Cathayornis	C. aberransis				An enantiornithine
	C. caudatus				Nomen dubium[24]
	C. yandica			"Partial skeleton."[22]	An enantiornithean
Cuspirostrisornis	C. houi				A possible avisaurid
Dapingfangornis	D. sentisorhinus				An enantiornithean
Eocathayornis	E. walkeri			"Partial skeleton."[22]	An enantiornithean
Gracilornis	G. jiufotangensis				An enantiornithean
Imparavis[25]	I. attenboroughi	Jianchang		An articulated, nearly complete specimen
Huoshanornis	H. huji				An enantiornithean
Largirostrornis	L. sexdentoris				An enantiornithean
Longchengornis	L. sanyanensis				An enantiornithean
Longipteryx	L. chaoyangensis				A longipterygid
Musivavis	M. amabilis			"A nearly complete and articulated skeleton preserved in a single slab."[26]	An euenantiornithean
Rapaxavis	R. pani				A longipterygid
Shangyang	S. graciles				An enantiornithean
Sinornis	S. santensis			"Partial skull [and] many nearly complete postcranial skeletons."[27]	An enantiornithean
Xiangornis	X. shenmi				An enantiornithean
Yuanchuavis	Y. kompsosoura				An pengornithid

Euornithines

Genus	Species	County	Member	Material	Notes	Images
Aberratiodontus	A. wui				Junior synonym of Yanornis martini[28]	Gansus zheni Shuilingornis angelai Piscivoravis lii Yanornis martini Yixianornis grabaui
Chaoyangia	C. beishanensis			"Partial skeleton."[27]	A basal euornithean
Gansus[29]	G. zheni			Multiple complete, articulated skeletons	A basal euornithean
Jianchangornis	J. microdonta	Jianchang			A basal euornithean
Mengciusornis	M. dentatus				A schizoourid
Parahongshanornis[30]	P. chaoyangensis				A hongshanornithid
Piscivoravis	P. lii				An ornithuromorph
Schizooura	S. lii	Jianchang			A schizoourid with long, forked tail feathers
Similiyanornis	S. brevipectus				An ornithuromorph
Shuilingornis[31]	S. angelai				A gansuid
Songlingornis	S. linghensis				An ornithuromorph
Yanornis	Y. martini				An ornithuromorph
Yixianornis	Y. grabaui			A near complete skeleton	An ornithuromorph
Zhongjianornis	Z. yangi			A complete skeleton	A basal euornithean[32]

Non-ornithothoracean theropods

A large theropod tooth representing a distinct taxon from Sinotyrannus is known.^[20]

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Genus	Species	County	Member	Material	Notes	Images
Chongmingia[33]	C. zhengi			A partial skeleton with preserved soft tissues	A jinguofortisid avialan	Confuciusornis sanctus Jeholornis prima Microraptor gui Sinotyrannus kazuoensis Wulong bohaiensis
Confuciusornis	C. sanctus				A primitive short-tailed avialan (pygostylian). Also present in the Yixian Formation
	C. jianchangensis	Liaoning
Cratonavis[34]	C. zhui	Jianchang		A complete skeleton with preserved feathers	A jinguofortisid avialan
Dalianraptor	D. cuhe				Nomen dubium, named from a forged artificially assembled specimen.
Jeholornis[3]	J. prima[3]				A jeholornithiform avialan, also present in the Yixian Formation[35]
	J. palmapenis[36]				A jeholornithiform avialan
Kompsornis	K. longicaudatus			"Nearly complete specimen".[37]	A jeholornithiform avialan
Microraptor	M. gui		Shangheshou Bed	Extremely common[19]	Could be synonym of Microraptor zhaoianus
	M. zhaoianus		Shangheshou Bed[19]	"At least [three] partial semiarticulated postcrania and several skulls."[38] Feathered integument is also preserved.[38]	A dromaeosaurid.
Neimengornis	N. rectusmim				A jeholornithiform avialan
Omnivoropteryx	O. sinousaorum				An omnivoropterygiform avialan
Sapeornis	S. angustis			"Nearly complete skeleton without skull."[39]	An omnivoropterygiform, a primitive short-tailed avialan
	S. chaoyangensis
Shenshiornis	Shenshiornis primita[40]				An omnivoropterygiform avialan
Similicaudipteryx	S. yixianensis				An oviraptorosaur
Sinotyrannus[41]	S. kazuoensis[41]				A tyrannosauroid[41]
Wulong[42]	W. bohaiensis[42]	Chaoyang, Liaoning[42]		Complete articulated skeleton (D2933).[42]	A dromaeosaurid

Crustaceans

Genus	Species	County	Member	Material	Notes	Images
Eosestheria	Eosestheria middendorfii[43]				A clam shrimp

Plants

Genus	Species	County	Member	Material	Notes	Images
Czekanowskia	C. rigida[44]				A member of Czekanowskiales, Dominant
Ginkgo	G. digitata[44]				A member of Ginkgoales
Elatocladus	E. pinnatus[44]				Conifer foliage
Pityolepis	P. ovatus[44]				Conifer cone
Leptostrobus	L. sinensis[44]				A member of Czekanowksiales, occasionally misspelled "Leptosthrobus"
Baiera	B. valida[44]				A member of Ginkgoales
	B. cf. gracilis[44]
Ginkgoites	G. trancata[44]				A member of Ginkgoales, dominant
	G. trancatus[44]
Podozamites	P. sp.[43]				Conifer foliage
Sphenopteris	S. sp.[43]				Seed plant foliage

See also

• Yixian Formation
• List of dinosaur-bearing rock formations