Paleobiota of the Yixian Formation

The Yixian Formation (simplified Chinese: 义县组; traditional Chinese: 義縣組; pinyin: Yìxiàn zǔ) is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans about 1.6 million years during the early Cretaceous period (Barremian-Aptian stage). It is known for its fossils, listed below.

The Yixian Formation is divided into the following subunits: (ages from Zhong et al., 2021 unless otherwise noted)

Upper Yixian (124.1 Ma) ("Jingangshan Bed") ("Dawangzhangzi Bed")
Upper Lava Unit
Jianshangou Unit (125.46 Ma)
Lower Lava Unit
Lujiatun Unit (125.76–125.68 Ma)

Sauropods

Genus	Species	County	Member	Material	Notes	Images
Dongbeititan	D. dongi	Beipiao	Jianshangou Bed	Partial postcrania	A basal titanosauriform	Euhelopus
cf. Euhelopus	cf. E. sp.		Lujiatun Bed	Isolated teeth	A basal titanosauriform
Liaoningotitan	L. sinensis			nearly complete skeleton	A basal titanosauriform
Ruixinia	R. zhangi	Beipiao		A partial articulated skeleton	A somphospondylan titanosauriform
Sauropoda spp.			Lujiatun & Jianshangou Beds	Isolated vertebrae and teeth	One or more species of sauropods, possibly titanosaurs, have been recovered from the Yixian Formation, though most remain undescribed

Ornithischians

The dinosaurs listed below were compiled in a survey by Xu and Norell in 2006, unless otherwise noted.

Genus	Species	County	Member	Material	Notes	Images
Bolong	B. yixianensis		Jianshangou Bed		An ornithopod	Jeholosaurus Liaoceratops Liaoningosaurus Psittacosaurus
Changmiania	C. liaoningensis		Lujiatun Bed	Two nearly complete skeletons	A basal ornithopod that may have dug burrows
Jeholosaurus	J. shangyuanensis	Beipiao	Lujiatun Bed	"Skull with associated vertebrae and hindlimb, skull with cervical vertebrae."	An ornithopod
Jinzhousaurus	J. yangi	Yixian	Dawangzhangzi Bed	"Nearly complete skull and skeleton."	An ornithopod
Liaoceratops	L. yanzigouensis	Beipiao	Lujiatun Bed	"[Two] nearly complete skulls, juvenile to adult."	A ceratopsian
Liaoningosaurus	L. paradoxus	Yixian	Dawangzhangzi Bed	"Partial skull [and] skeleton."	A small ankylosaur
Psittacosaurus	P. lujiatunensis	Beipiao	Lujiatun & Jianshangou Beds	Thousands of specimens in the Lujiatun Bed, somewhat less common in the Jianshangou Bed	A ceratopsian

Theropods

The dinosaurs listed below were compiled in a survey by Xu and Norell in 2006, unless otherwise noted.

Avialans

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	Member	Material	Notes	Images
Abitusavis	A. lii		"Nearly complete skeleton."		Changchengornis Confuciusornis sanctus Eogranivora Hongshanornis Liaoningornis Liaoxiornis Shanweiniao Yixianosaurus
Archaeorhynchus	A. spathula	Dawangzhangzi Bed		An early, advanced short-tailed bird (ornithuran)
Changchengornis	C. hengdaoziensis	Jianshangou Bed	"Nearly complete skeleton."	A confuciusornithid
Confuciusornis	C. chuonzhous			Junior synonym of Confuciusornis sanctus
	C. dui	Jianshangou Bed	"[Two] skeletons."
	C. feducciai	Jianshangou Bed
	C. sanctus	Jianshangou and Dawangzhangzi Beds	"Hundreds of complete skeletons."	A primitive short-tailed bird (pygostylian), also present in the Jiufotang Formation
	C. suniae			Junior synonym of Confuciusornis sanctus
Dalingheornis	D. liweii	Dawangzhangzi Bed		An Enantiornithine
Eoenantiornis	E. buhleri	Jianshangou Bed	"Nearly complete skeleton."	An entantiornithine
Eogranivora	E. edentulata	Dawangzhangzi Bed	"nearly complete skeleton with skull"	An ornithuromorph
Iteravis	I. huchzermeyeri			An ornithuromorph
Jinzhouornis	J. yixianensis	Jianshangou Bed		A pygostylian, a junior synonym of Confuciusornis sanctus
Jinzhouornis	J. zhangjiyingia	Jianshangou Bed		Junior synonym of C. sanctus
Jixiangornis	J. orientalis	Jianshangou Bed		A basal avialan, also present in the Jiufotang Formation
Hongshanornis	H. longicresta	Jianshangou and Dawangzhangzi Beds	4 specimens	An ornithuromorph
Jibeinia	J. luahera			Previously regarded as Yixian, horizon reassigned to the Huajiying Formation by Jin et al., 2008.
Liaoningornis	L. longidigitris	Lujiatun Bed	"Partial skeleton."	An enantiornithine.
Liaoxiornis	L. delicatus	Dawangzhangzi Bed		Considered a nomen dubium because the name is based on remains of a hatchling entantiornithine and cannot be confidently matched with the adult form.
Lingyuanornis	L. parvus	Dawangzhangzi Bed		Junior objective synonym of Liaoxiornis delicatus, a nomen dubium.
Longicrusavis	L. houi	Dawangzhangzi Bed		An ornithuromorph
Longirostravis	L. hani	bed unknown		An enantiornithine
Protopteryx	P. fengningensis			Previously regarded as Yixian, horizon reassigned to the Huajiying Formation by Jin et al., 2008.
Mirusavis	M. parvus		Partial skeleton.	An immature female enantiornithine preserved with medullary bone tissue.
Shanweiniao	S. cooperorum	Dawangzhangzi Bed		An enantiornithine.
Vescornis	V. hebeiensis			Previously regarded as Yixian, horizon reassigned to the Huajiying Formation by Jin et al., 2008.
Yixianosaurus	Y. longimanus	Dawangzhangzi Bed		An anchiornithid
Zhongornis	Z. haoae	Dawangzhangzi Bed		A primitive avialan with a short but non-pygostylian tail

Dromaeosaurs and troodontids

Genus	Species	County	Member	Material	Notes	Images
Changyuraptor	C. yangi	Jianchang		A complete articulated specimen with extensive feathering.	A dromaeosaurid	Changyuraptor Daliansaurus Graciliraptor Jianianhualong Liaoningvenator Mei Sinornithosaurus millenii Sinovenator Sinusonasus Tianyuraptor Zhenyuanlong Zhongjianosaurus
Daliansaurus	D. liaoningensis	Beipiao	Lujiatun Bed	A very complete specimen.	A troodontid
Graciliraptor	G. lujiatunensis	Beipiao	Lujiatun Bed	An incomplete specimen.	A dromaeosaurid
Jianianhualong	J. tengi	Beipiao	Dawangzhangzi Bed	A very complete specimen with feather impressions.	A troodontid
Liaoningvenator	L. curriei	Beipiao		A very complete specimen.	A troodontid
Mei	M. long	Beipiao	Lujiatun Bed		A small troodontid fossilized in a sleeping position
Sinornithosaurus	S. haoiana	Yixian	Dawangzhangzi Bed		Might be a junior synonym of Sinornithosaurus millenii.
Sinornithosaurus	S. millenii	Beipiao	Jianshangou Bed	Three specimens with skulls and postcrania, two with preserved feathers. Feathered integument is also preserved.	A dromaeosaurid, the first ever found with feather impressions.
Sinovenator	S. changii	Beipiao	Lujiatun Bed	Three specimens with partial skulls and postcrania. Hundreds of additional specimens known but undescribed.	A troodontid
Sinusonasus	S. magnodens	Beipiao	Lujiatun Bed		A troodontid
Tianyuraptor	T. ostromi	Lingyuan	Dawangzhangzi Bed		A dromaeosaurid
Zhenyuanlong	Z. suni	Jianchang		One nearly complete skeleton with preserved feathers, including long tail feathers and large wing feathers.	A dromaeosaurid
Zhongjianosaurus	Z. yangi	Lingyuan		A partial skeleton including an arm, both legs, vertebrae, ribs and most of the tail.	A microraptorian dromaeosaurid with very long legs.
Undescribed deinonychosaur/possible troodontid			Dawangzhangzi Bed	One specimen with feather imprints	A possible troodontid.
Undescribed troodontid	Specimen CAGS-IG01-004		Lujiatun Bed	Skull and partial skeleton	A troodontid similar to Mei.
Unnamed dromaeosaurid	Specimen NGMC 91	Lingyuan	Dawangzhangzi Bed	Complete specimen with feather imprints	A juvenile dromaeosaurid that may be a specimen of Sinornithosaurus millenii. Informally nicknamed "Dave".

Other theropods

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
Beipiaosaurus	B. inexpectus	Beipiao	Jianshangou Bed	"Incomplete skeleton with integument."	A therizinosaur	Beipiaosaurus Caudipteryx zoui Dilong Incisivosaurus Jianchangosaurus Protarchaeopteryx Shenzhousaurus Sinocalliopteryx Sinosauropteryx prima Yutyrannus
Caudipteryx	C. dongi	Beipiao	Jianshangou Bed	"[One] partial postcranium with feather imprints."	Oviraptorosaurs
	C. zoui	Beipiao	Jianshangou Bed	Common, only over a small region
	C. sp.
Dilong	D. paradoxus	Beipiao	Lujiatun & Jianshangou Bed	Rare	A tyrannosauroid
Grallator			lower Jianshangou Bed		Footprints belonging to the Grallator form taxon, belonging to a small theropod. Of known Yixian theropods, the footprints most closely match Caudipteryx.
Hexing	H. qingyi	Beipiao	Lujiatun		A primitive ornithomimosaur
Huaxiagnathus	H. orientalis	Beipiao	Jianshangou Bed		A compsognathid
Incisivosaurus	I. gauthieri	Beipiao	Lujiatun Bed	"[One] skull [and a] partial cervical."	An oviraptorosaur
Jianchangosaurus	J. yixianensis	Jianchang		A nearly complete juvenile specimen with feather impressions.	A therizinosaur
Ningyuansaurus	N. wangi			Complete skeleton with feather impressions.	An oviraptorosaur
Protarchaeopteryx	P. robusta	Beipiao	Jianshangou Bed	"Nearly complete skull and skeleton, at least [two] individuals."	A possible relative of Incisivosaurus
Raptorex	R. kriegsteini				A tyrannosaurid, probably from higher Mongolian strata.
Scansoriopteryx	S. heilmanni				Initially reported from the Dawangzhangzi Bed, probably from the Daohugou Beds instead.
Shenzhousaurus	S. orientalis	Beipiao	Lujiatun Bed	"Articulated skull and incomplete skeleton."	A primitive ornithomimosaur
Similicaudipteryx	S. yixianensis			Two specimens	An oviraptorosaur, also present in the Jiufotang Formation
Sinocalliopteryx	S. gigas	Beipiao	Jianshangou Bed		A large compsognathid
Sinosauropteryx	S. prima	Beipiao & Lingyuan	Jianshangou & Dawangzhangzi Beds	Four nearly complete specimens	A compsognathid. The first non-avian dinosaur found with feather impressions.
Sinosauropteryx	S.? sp.	Beipiao	Jianshangou Bed	One specimen (GMV 2124) with partial skull, postcrania, and preserved feathers	An unnamed coelurosaur originally described as a specimen of Sinosauropteryx, later found to be a new genus and species.
Xingtianosaurus	X. ganqi	Liaoning	Dakangpu Bed	One nearly complete specimen (IVPP V13390), minus the head	An oviraptorosaur
Yutyrannus	Y. huali		Unknown	Three nearly complete skeletons of various ages	A large tyrannosauroid
Unnamed theropod	Not yet described	Yixian	Lujiatun Bed	Partial post-cranial skeleton	A possible carnosaur

Pterosaurs

The pterosaurs listed below were compiled in a survey by Wang and Zhou in 2006, unless otherwise noted.

Genus	Species	County	Member	Material	Notes	Images
Beipiaopterus	B. chenianus		Jianshangou Bed		A ctenochasmatid	Feilongus Gladocephaloideus Haopterus Moganopterus Ningchengopterus
Boreopterus	B. cuiae		Jianshangou Bed		A boreopterid
Cathayopterus	C. grabaui		Dawangzhangzi Bed		A ctenochasmatid
Elanodactylus	E. prolatus		Jianshangou Bed		A ctenochasmatid
Eopteranodon	E. lii	Beipiao			A tapejarid
Eopteranodon	E. yixianensis	Beipiao			A tapejarid
Eosipterus	E. yangi		Jianshangou Bed		A ctenochasmatid
Gegepterus	G. changae		Jianshangou Bed		A ctenochasmatid
Gladocephaloideus	G. jingangshanensis		Jianshangou Bed		A ctenochasmatid
Haopterus	H. gracilis		Jianshangou Bed		An ornithocheirid
Luchibang	L. xingzhe			One nearly complete articulated skeleton (ELDM 1000)	An istiodactylid, the most complete known
Moganopterus	M. zhuiana		Lujiatun bed?		A ctenochasmatid
Ningchengopterus	N. liuae		Jianshangou or Dawangzhangzi bed		A pterodactyloid
Nurhachius	N. sp.		Jingangshan Member	An incomplete specimen	An istiodactylid
Pterofiltrus	P. qiui		Jianshangou Bed		A ctenochasmatid
Zhenyuanopterus	Z. longirostris		Jianshangou Bed		A boreopterid. May be adult form of Boreopterus.

Misc. reptiles

Choristoderans

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	Member	Material	Notes	Images
Hyphalosaurus	H. lingyuanensis	Dawangzhangzi Bed			Hyphalosaurus baitaigouensis Monjurosuchus splendens
Hyphalosaurus	H. baitaigouensis	Jingangshan Bed	Thousands of specimens
Monjurosuchus	M. splendens	Dawangzhangzi Bed
Sinohydrosaurus	S. lingyuanensis	Dawangzhangzi Bed		Junior synonym of Hyphalosaurus lingyuanensis

Lizards

Genus	Species	Member	Notes	Images
Dalinghosaurus	D. longidigitus	Jianshangou Bed	A lizard related to shinisaurs	Dalinghosaurus Xianglong
Liushusaurus	L. acanthocaudata	Jianshangou or Dawangzhangzi bed	A lizard related to geckos and skinks
Xianglong	X. zhaoi	Jianshangou Bed	A gliding lizard related to chameleons and dragon lizards
Yabeinosaurus	Y. tenuis	Dawangzhangzi & Jingangshan Beds	A lizard related to geckos and skinks

Turtles

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	Member	Notes	Images
Manchurochelys	M. liaoxiensis	Jianshangou Bed	Reclassified as Ordosemys liaoxiensis	Ordosemys
Manchurochelys	M. manchoukuoensis	Jingangshan Bed
Ordosemys	O. liaoxiensis	Jianshangou Bed

Mammals

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.

The mammals listed below were compiled in a survey by Meng and colleagues in 2006, unless otherwise noted.

Genus	Species	County	Member	Notes	Images
Acristatherium	A. yanensis	Beipiao	Lujiatun Bed	A eutherian	Eomaia Gobiconodon zofiae Jeholodens Repenomamus robustus Yanoconodon
Akidolestes	A. cifellii	Lingyuan	Dawangzhangzi Bed	A spalacotheriid "symmetrodont"
Ambolestes	A. zhoui	Nincheng	Jianshangou Bed	A eutherian
Chaoyangodens	C. lii	Lingyuan	Dawangzhangzi Bed	A eutriconodont
Eomaia	E. scansoria	Lingyuan	Dawangzhangzi Bed	A tribosphenidan, possibly a eutherian or stem-therian
Gobiconodon	G. zofiae	Beipiao	Lujiatun Bed	A gobiconodont
Gobiconodon	G. luoianus		Lujiatun Bed	A gobiconodont; junior synonym of G. zofiae
Jeholodens	J. jenkinsi	Chaoyang	Jianshangou Bed	A eutriconodont
Juchilestes	J. liaoningensis	Beipiao	Lujiatun Bed	An amphidontid
Jueconodon	J. cheni			A eutriconodont
Maotherium	M. sinensis	Chaoyang	Jianshangou Bed	A zhangeotheriid "symmetrodont"
Maotherium	M. asiaticus	Beipiao	Lujiatun Bed	A zhangeotheriid "symmetrodont"
Meemannodon	M. lujiatunensis	Beipiao	Lujiatun Bed	A gobiconodont
Origolestes	O. lii			A zhangeotheriid "symmetrodont"
Repenomamus	R. giganticus	Beipiao	Lujiatun Bed	A gobiconodont
Repenomamus	R. robustus	Beipiao	Lujiatun Bed	A large gobiconodont, which ate small dinosaurs
Sinobaatar	S. lingyuanensis	Lingyuan	Jianshangou and Dawangzhangzi Beds	A multituberculate
Sinodelphys	S. szalayi	Lingyuan	Dawangzhangzi Bed	A therian, initially interpreted as a metatherian and later reinterpreted as a eutherian
Yanoconodon	Y. allini	Fengning		A eutricondodont
Zhangheotherium	Z. quinquecuspidens	Chaoyang	Jianshangou Bed	A zhangeotheriid "symmetrodont"

Amphibians

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	Notes	Images
Callobatrachus	C. sanyanensis	Sihetun	Jianshangou Bed	Junior synonym of Liaobatrachus	Liaobatrachus
Laccotriton	L. subsolanus	Paozhanggou	Fengshan Bed	A urodelan
Liaobatrachus	L. grabaui	Sihetun	Jianshangou Bed	A spadefoot toad
Liaobatrachus	L. zhaoi	Beipiao & Heitizigou	Lujiatun Bed & Jianshangou Bed	A spadefoot toad
Mesophryne	M. beipiaoensis	Beipiao & Heitizigou	Lujiatun Bed & Jianshangou Bed	Junior synonym of Liaobatrachus
Sinerpeton	S. fengshanensis	Paozhanggou	Fengshan Bed	A urodelan

Fish

Genus	Species	Member	Abundance	Notes	Images
Hybodontoidea indet.	Family, genus and species indeterminate			An elasmobranch known from a single dorsal fin spine	Lycoptera Mesomyzon Protopsephurus Sinamia
Lycoptera	L. davidi	Jianshangou & Dawangzhangzi Beds	Also present in the Jiufotang Formation & Huajiying Formation	An osteoglossiform
	L. muroii	Jingangshan Bed
	L. sinensis	Jianshangou Bed
Mesomyzon	M. mengae			A lamprey
Peipiaosteus	P. pani	Jianshangou & Dawangzhangzi Bed	Also present in the Jiufotang Formation	A peipiaosteid fish related to sturgeons
Protopsephurus	P. liui	Dawangzhangzi Bed	Also present in the Jiufotang & Huajiying Formations	A paddlefish
Sinamia	S. zdanskyi	Jianshangou Bed		A bowfin
Yanosteus	Y. longidorsalis		Also present in the Huajiying Formation	A peipiaosteid

Invertebrate fauna of the Yixian Formation

The invertebrate species listed below follow a survey by Chen and colleagues published in 2005, unless otherwise noted.

Arachnids

The arachnid species listed below follow a catalogue compiled by Dunlop, Penney and Jekel in 2010, unless otherwise noted.

Genus	Species	Notes
?Araneus	A.? aethus	Orb-weaver spiders
	A.? beipiaoensis
	A.? liaoxiensis
	A.? reheensis
Cretaraneus	C. liaoningensis	A nephiline spider
?Gnaphosa	G.? liaoningensis	A ground spider
?Theridion	T.? atalus	A tangle web spider

Beetles (Coleoptera)

Genus	Species	County	Notes
Anoixis	A. complanus		A desmatin click beetle
Apoclion	A. antennatus		Desmatin click beetles
	A. clavatus
	A. dolini
Coptoclava	C. longipoda		A beetle
Desmatinus	D. cognatus		A desmatin click beetle
Fortiseode	F. pervalimand		An eodromeine trachypachid beetle
Glaresis	G. orthochilus		A laresid scarab beetle
Hydrophilopsia	H. gracilis		Hydrophiloid water scavenger beetles
	H. hydraenoides
	H. shatrovskiyi
Lasiosyne	L. integera	Huangbanjigou Village, Liaoning Province, northeastern China.	A lasiosynid beetle.
Lasiosyne	L. parva	Huangbanjigou Village, Liaoning Province, northeastern China.	A lasiosynid beetle.
Liaoximordella	L. hongi		A mordellid beetle
Mirimordella	M. gracilicruralis		A mordellid beetle
Oxyporus	O. yixianus		An oxyporine rove beetle
Paradesmatus	P. dilatatus		A desmati click beetle
Parageotrupes	P. incanus		A Geotrupine scarab beetle
Sinocupes	S. validus		A beetle
Sinosperchopsis	S. silinae		A hydrophiloid water scavenger beetle
Sinoxytelus	S. breviventer		Oxyteline rove beetles
	S. euglypheus
	S. longisetosus

Crustaceans

Genus	Species	County	Member	Notes
Chenops	C. oblongus			Notostracans
Chenops	C. yixianensis			Notostracans
Cricoidoscelosus	C. aethus			Junior synonym of Palaeocambarus
Cypridea	C. (Cypridea) liaoningensis		Jianshangou Bed	Ostracods
	C. (C.) sihetunensis		Jianshangou Bed
	C. (C.) veridica arguta		Jingangshan Bed
	C. (C.) sp.		Jianshangou Bed
	C. (Ulwellia) beipiaoensis	Beipiao	Jianshangou Bed
Damonella	D. formosa		Jianshangou Bed	An ostracod
Darwinula	D. leguminella		Jianshangou Bed	An ostracod
Diestheria	D. jeholensis		Jianshangou Bed	Clam shrimps
	D. yixianensis		Dawangzhangzi Bed
	D.? sp.		Jianshangou Bed
Eosestheria	E. jingangshanensis		Jingangshan Bed	Clam shrimps
	E. lingyuanensis		Dawangzhangzi Bed
	E. aff. middendorfii		Jingangshan Bed
	E. ovata		Jianshangou Bed
	E. sihetunensis		Jianshangou Bed
Eosestheriopsis	E. gujialingensis		Jianshangou Bed	A clam shrimp
Jeholops	J. hongi			A notostracan
Liaoningogriphus	L. quadripartitus		Jianshangou and Dawangzhangzi beds	A shrimp
Lycopterocypris	L. infantilis		Jianshangou Bed	An ostracod
Mantelliana	M. sp.		Jianshangou Bed	An ostracod
"Mongolarachne"	"M." chaoyangensis		Dawangzhangzi Beds	Junior synonym of Palaeocambarus
Mongolianella	M. cf. palmosa		Jianshangou Bed	An ostracod
Palaeocambarus	P. licenti			A crayfish
Rhinocyrpis	R. jurassica		Jianshangou Bed	An ostracod
Timiriasevia	T. jianshangouensis		Jianshangou Bed	An ostracod
?Yanjiestheria	Y.? beipiaoensis	Beipiao	Jianshangou Bed	A clam shrimp
Yanshania	Y. dabeigouensis		Jianshangou Bed	An ostracod

Dragonflies (Odonata)

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.

The dragonfly species listed below follow a review compiled by Zhang, Ren and Panf in 2008, unless otherwise noted.

Genus	Species	County	Member	Abundance	Notes	Images
Abrohemeroscopus	A. mengi				A dragonfly	Sinaeschnidia sp.
Aeschnidium	A. heishankowense				Reclassified as Sinaeschnidia heishankowense
Aeschnidium	A. sp.				Reclassified as Sinaeschnidia heishankowense
Archaeogomphus	A. labius			Nymphs	Reclassified as Yixiangomphus labius, which is a junior synonym of Sinaeschnidia cancellosa
Bellabrunetia	B. catherinae				A dragonfly
Chrysogomphus	C. beipiaoensis				A dragonfly
Dissurus	D. liaoyuanensis			Poorly preserved nymph	Reclassified as Sinaeschnidia cf. cancellosa
Dracontaeschnidium	D. orientale				A dragonfly
Hebeiaeschnidia	H. fengningensis				A dragonfly
Huaxiagomphus	H. taushanensis				A dragonfly
Liogomphus	L. yixianensis				A dragonfly
Mesocordulia	M. boreala				A corduliid dragonfly
Palaeogomphus	P. labius				A dragonfly, reclassified as of Yixiangomphus labius, which is a junior synonym of Sinaeschnidia cancellosa
Parapetala	P. liaoningensis				A dragonfly
Parapetala	P. yixianensis		Jianshangou Unit
Protoliupanshania	P. wangi		Jianshangou Unit		A liupanshaniid dragonfly
Pseudocymatophlebia	P. bisecta	Ningcheng County		A well-preserved specimen.	An aktassiid dragonfly
Pseudoliupanshania	P. magnanicellula		Jianshangou Unit
Pseudosamarura	P. largina			One specimen, nymph	Reclassified as Sinaeschnidia cf. cancellosa
Rudiaeschna	R. limnobia				An aeshnid dragonfly
Sinaeschnidia	S. heishankowense		Jianshangou & Dawangzhangzi Beds	Adults and nymphs
	S. cancellosa				Junior synonym of S. heishankowense
	S. sp.			Indeterminate nymph specimens	Some nymph specimens have been given their own genera and species though probably belong so S. heishankowense but too poorly preserved to be certain
Sinogomphus	S. taoshanensis				A dragonfly
Sinojagoria	S. imperfecta				A dragonfly
Sopholibellula	S. amoena				Dragonflies
Sopholibellula	S. eleganti				Dragonflies
Stylaeschnidium	S. rarum				A dragonfly
Telmaeshna	T. paradoxica	Beipiao			A dragonfly
Turanophlebia	T. liaoningensis	Beipiao	Jianshangou Unit		A tarsophlebiid dragonfly.
Yixiangomphus	Y. labius			Nymphs	Junior synonym of Sinaeschnidia cancellosa

Flies (Diptera)

Genus	Species	Member	Notes
Alleremonmus	A. xingi	Jianshangou Bed	A brachyceran fly
Atalosciophila	A. yanensis		A mycetophilid gnat
Chironomaptera	C. gregaria		A phantom midge
Gigantoberis	G. liaoningensis		A soldier fly
Lichnoplecia	L. kovalevi		A protopleciid fly
Palaepangonius	P. eupterus		A horse-fly
Protapiocera	P. megista		An asiloid fly
Protempis	P. minuta		A brachyceran fly
Protonemestrius	P. jurassicus		A tangle-veined fly

Wasps (Hymenoptera)

Genus	Species	County	Member	Notes
Abropelecinus	A. annulatus	Beipiao		An iscopinine pelecinid
Angaridyela	A. robusta		Jianshangou Bed	A sawfly
Azygopelecinus	A. clavatus	Beipiao		An iscopinine pelecinid
Chengdeserphus	C. petidatus			A proctotrupid wasp
Cretevania	C. exquisita	Beipiao		Hatchet wasps
	C. pristine		Jianshangou bed
	C. vesca
Hoplitolyda	H. duolunica			The largest known sawfly ever
Liaotoma	L. linearis			A xyelotomid woodwasp
Manlaya	M. flexuosus			An aulacid woodwasp
Procretevania	P. exquisita			Reclassified as Cretevania spp.
	P. pristine
	P. vesca
Rudisiricius	R. belli			Praesiricid sawflies
	R. celsus
	R. crassinodus
Scolichneumon	S. rectivenius			An ichneumonoid wasp
Sinopelecinus	S. viriosus			A pelecinid
Tanychora	T. exquisita		Jianshangou Bed	An ichneumon wasp

Other insects

Genus	Species	County	Member	Notes	Images
Abrigramma	A. calophleba			A kalligrammatid lacewing
Alloraphidia	A. bliquivenatica			Snakeflies
Alloraphidia	A. longistigmasa		Jianshangou Bed	Snakeflies
Archeraphidia	A. shangyuanensis			A snakefly
Baissopterus	B. liaoningensis			A snakefly
Caenoephemera	C. shangyuanensis		Jianshangou Bed	A mayfly
Caloraphidia	C. glossophylla			A snakefly
Choromyrmeleon	C. othneius			An antlion
Circulaboilus	C. aureus			A grig
Cretophasmomima	C. melanogramma			A stick insect	Cretophasmomima, a stick insect
?Ephemeropsis	?E. trisetalis		Jianshangou and Jingangshan beds	A mayfly. Chinese specimens probably represent species of Epicharmeropsis
Epicharmeropsis	E. hexavenulosus	Pingquan		Mayflies
Epicharmeropsis	E. quadrivenulosus	Beipiao	Jianshangou Bed	Mayflies
Hagiphasma	H. paradoxa		Jianshangou Bed	A stick insect
Ilerdocossus	I. beipiaoensis			Palaeontinid hemipterans
	I. exiguus
	I. exquisitus
	I. fengningensis
	I. hui
	I. pingquanensis
Ithigramma	I. multinervia			Kalligrammatid lacewings
Kalligramma	K. liaoningensis		Jianshangou Bed	Kalligrammatid lacewings
Karatavoblatta	K. formosa			A cockroach
Liaoaphidia	L. fornicata			A snakefly
Liaonemobius	L. tanae			A sword-tail cricket
Longicellochrysa	L. yixiana			A mesochrysopid lacewing
Mesascalaphus	M. yangi			An owlfly
Mesolygaeus	M. laiyangensis			A water bug
Metabittacus	M. colosseus		Jianshangou Bed	A scorpionfly
Miracossus	M. gongi			Palaeontinid hemipterans
Miracossus	M. ingentius			Palaeontinid hemipterans
Nipponoblatta	N. acerba		Jianshangou Bed	A cockroach
Oloberotha	O. sinica			A beaded lacewing
Oregramma	O. aureolosa			Kalligrammatid lacewings
Oregramma	O. illecebrosa			Kalligrammatid lacewings
Pseudopulex	P. magnus			Stem-fleas
Pseudopulex	P. tanlan			Stem-fleas
Renphasma	R. sinica			A stick insect
Saurophthirus	S. exquisitus			Stem-fleas
Saurophthirus	S. laevigatus			Stem-fleas
Sinochresmoda	S. magnicornia			A chresmodid water-skiing insect
Sinosharaperla	S. zhaoi	Beipiao		A stonefly
Sinoviparosiphum	S. lini			An aphid
Sophogramma	S. lii		Jianshangou Bed	Kalligrammatid lacewings
Sophogramma	S. pingquanica			Kalligrammatid lacewings
Tetraphelerus	T. laetus			A moth
Tyrannopsylla	T. beipiaoensis			A stem-flea
Varicapitatus	V. sinuolatus	"Huangbanjigou, Chaomidian Village, Beipiao City."		A hemipteran
Unnamed Vitimotauliidae	Unnamed			A caddisfly pupa, likely belonging to the Vitimotauliidae

Molluscs

Genus	Species	Member	Notes
Amplovalvata	A. sp.	Jianshangou Bed	A gastropod
Arguniella	A. lingyuanensis	Jianshangou Bed	A bivalve, also present in the Jiufotang and Fuxin Formations
Arguniella	A. yanshanensis	Jianshangou Bed	A bivalve, also present in the Jiufotang Formation
Bithynia	B. haizhouensis	Jingangshan Bed	A gastropod
Corbicula	C. anderssoni	Jianshangou Bed	Reclassified as Sphaerium anderssoni
Corbicula	C. jeholense	Jianshangou Bed	Reclassified as Sphaerium jeholense
Gyraulus	G. sp.	Jianshangou Bed	A ramshorn snail
Probaicalia	P. vitimensis	Jianshangou Bed	A gastropod
Ptychastylus	P. harpaeformis	Jianshangou Bed	Gastropods
Ptychastylus	P. cf. phillipi	Jianshangou Bed	Gastropods
Sphaerium	S. anderssoni	Jianshangou Bed	A fingernail clam, also present in the Jiufotang Formation
	S. jeholense		Junior synonym of S. anderssoni
	S. selenginense		Junior synonym of S. anderssoni
?Viviparus	V.? cf. matsumotoi	Jingangshan Bed	A snail

Flora of the Yixian Formation

Conifers

The coniferous trees and shrubs listed below were compiled in a survey by Wang and colleagues in 2006, unless otherwise noted.

Genus	Species	Member	Notes
Brachyphyllum			A cypress-like conifer
Cephalotaxopsis			A yew
Cunninghamia			A cypress
Elatides			A cypress
Elatocladus	E. leptophyllus		Conifers of uncertain classification
Elatocladus	E. manchurica		Conifers of uncertain classification
Liaoningocladus	L. boii	Jingangshan Bed	A conifer of uncertain classification
Pagiophyllum			A cypress-like conifer
Pityocladus			A pine
Pityolepis	P. sp.		A pine
Pityophyllum	P. cf. lindstroemi		A pine
Pityostrobus			A pine
Podozamites	P. lanceolatus		A conifer of uncertain classification
Schizolepis	S. jeholensis
?Sequoia	S.? jeholensis
Taxus			A yew
Torreya			A yew
Yanliaoia	Y. sinensis

Ferns

Genus	Species	Notes
Cladophlebis	C. spp.
Coniopteris	C. sp.
Onychiopsis	O. elongata	Junior synonym of O. psilotoides
Onychiopsis	O. psilotoides
?Ruffordia	R.? sp.

Flowering plants

Genus	Species	County	Member	Notes	Images
Archaefructus	A. eoflora		Jianshangou Bed	A primitive, aquatic angiosperm	Archaefructus
	A. liaoningensis		Jianshangou Bed
	A. sinensisis		Dawangzhangzi Bed
Callianthus	C. dilae	Liaoning		A plant with true flowers
?Davallia	D.? niehhutzuensis
Erenia	E. stenoptera	Liaoning		Actually a specimen of Callianthus
Leefructus	L. mirus			A eudicot
Liaoxia	L. chenii
?Potamogeton	P.? jeholensis
Ranunculus	R. jeholensis			Junior synonym of Potamogeton jeholensis
Sinocarpus	S. decussatus			A primitive eudicot

Ginkgos

Genus	Species	County	Member	Abundance	Notes	Images
Baiera	B. cf. gracilis
Baiera	B. orientalis
Czekanowskia	C. rigida
Ginkgo	G. apodes
Ginkgoites	G. sibiricus
Leptostrobus	L. sp.
?Nageiopsis	N.? sp.
Phoenicopsis	P. cf. augustifolia
Solenites	S. sp.
Sphenobaiera	S. longifola

Other plants

Genus	Species	County	Member	Notes
Chaoyangia	C. liangii			A gnetale gymnosperm
Chaoyangicarpus	C. liangii			Junior synonym of Chaoyangia liangii
Ephedra	E. sp.			A gymnosperm
Equisetum	E. sp.			A horsetail
Eragrosites	E. changii			A grass-like gnetale gymnosperm
Siphonospermum	S. simplex	Beipiao	Jianshangou Bed	A gnetale gymnosperm
Tyrmia	T. sp.			A cycad