Where: Liaoning, China (41.6° N, 120.8° E: paleocoordinates 44.1° N, 122.9° E)
• coordinate estimated from map
• outcrop-level geographic resolution
When: Yixian Formation (Jehol Group), Late/Upper Barremian (130.0 - 125.5 Ma)
• The Yixian Formation can be subdivided into five units, in ascending order, Lujiatun unit, Lower Lava, Jianshangou unit, Upper Lava, Dawangzhangzi unit, Jingangshan unit, and Huanghuashan unit. Most of the Jehol fossils from the Yixian Formation are preserved in four beds, that is, the Lujiatun bed (recalculated age is 124.0 ± 1.0/1.3 Ma, He et al., 2006), the Jianshangou bed (125.43 ± 0.50/0.88 Ma, Swisher et al., 1999), the Dawangzhangzi bed, and Jinggangshan bed (~122 Ma, Smith et al., 1995).U-Pb dating suggests that the Huangbanjigou section ranges from 124.9 ± 1.7 Ma to 122.8 ± 1.6 Ma (Yang et al., 2007). Chang et al. (2017) obtained Ar/Ar ages of 125.8 ± 1.0 Ma and 126.0 ± 0.8 Ma from the Lujiatun Unit, the lowest part of the Yixian Formation, below the lacustrine shales.
•He et al. (2004) reported a 40Ar/39Ar age of 120.3 ± 0.7 Ma for a tuff layer in the lower part of the Jiufotang Formation, and Chang et al. (2009) obtained a 40Ar/39Ar age of 122.1 ± 0.3 Ma for a tuff layer from the lowermost part of the Jiufotang Formation. Yu et al. (2021) dated an ash bed just above the Yixian/Jiufotang formation boundary to 122.0 ± 0.9 Ma and three tuff beds from the Xiaotaizi section to 118.9 ± 0.8 Ma, 118.8 ± 0.6 Ma, and 118.6 ± 1.1 Ma. These ages suggest that the Jiufotang Formation in Jianchang Basin was deposited at ca. 122.0–118.9 Ma.
•Olierrok et al. (2019) used a selection of U-Pb and 40Ar-39Ar geochronology to place the Barremian–Aptian boundary (the base of the Chron M0r) between 123.8 and 121.8 Ma. The GTS 2020 uses an age of 121.4 Ma for the base of the Aptian, and multiproxy orbital tuning gives an age of 120.2 Ma for the Barremian-Aptian boundary (Leandro et al., 2022). Therefore, the Yixian Formation should be entirely Late Barremian, with the Jiufotang Formation deposited in the Early Aptian (or latest Barremian at its base).
• group of beds-level stratigraphic resolution
Environment/lithology: lacustrine - large; lithified, tuffaceous mudstone
Size classes: macrofossils, mesofossils
Preservation: adpression
Collection methods: Repository: Geological Museum of China, Beijing
Primary reference: D. Ren. 1995. Insecta. In D. Ren, L.W. Lu, Z.G. Guo, S.A. Ji (eds.), Faunae and stratigraphy of Jurassic-Cretaceous in Beijing and the adjacent areas 47-121 [M. Clapham/M. Clapham]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 138436: authorized by Matthew Clapham, entered by Matthew Clapham on 18.01.2013, edited by Jered Karr
Creative Commons license: CC BY (attribution)
Taxonomic list
Insecta | |
"Alleremonomus xingi n. gen. n. sp." = Alleremonomus xingi7, "Alleremonomus liaoningensis n. sp." = Alleremonomus xingi7, Lepteremochaetus lithoecius n. gen. n. sp.5
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"Pauromyia oresbia n. gen. n. sp." = Sharasargus oresbius5, "Allomyia ruderalis n. gen. n. sp." = Sinallomyia ruderalis5, "Helempis yixianensis n. gen. n. sp." = Ovisargus (Helempis) yixianensis5, "Helempis eucalla n. sp." = Ovisargus eucalla5
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Protempis minuta n. sp.5
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Eopangonius pletus n. gen. n. sp.5
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Palaepangonius eupterus n. gen. n. sp.5
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Florinemestrius pulcherrimus n. gen. n. sp.5, Protonemestrius jurassicus n. sp.5, Protonemestrius beipiaoensis n. sp.5
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"Liaocossus beipiaoensis n. gen. n. sp." = Ilerdocossus beipiaoensis10, "Liaocossus exiguus n. gen. n. sp." = Ilerdocossus exiguus10, "Liaocossus hui n. gen. n. sp." = Ilerdocossus hui10, Miracossus ingentius n. gen. n. sp.10
"Liaocossus beipiaoensis n. gen. n. sp." = Ilerdocossus beipiaoensis10 Ren et al. 1998 true bug LB97101
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"Anthoscytina aphthosa n. sp." = Stellularis aphthosa11 Ren et al. 1998 froghopper LB97202, 97201, 97203-97205, 97207-97216
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Lapicixius decorus n. gen. n. sp.11
Lapicixius decorus n. gen. n. sp.11 Ren et al. 1998 planthopper LB97152(3), 97150(1), 97154, 97155(6), 97157, 97158(9), 97160, 97161(2), 97163, 97164
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Liaonemobius tanae n. gen. n. sp.6
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Nipponoblatta acerba n. sp.
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Sibirobittacus atalus n. sp.3, Megabittacus colosseus n. gen. n. sp.3, Megabittacus beipiaoensis n. sp.3
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Orthophlebia liaoningensis n. sp.3
Orthophlebia liaoningensis n. sp.3 Ren 1997 scorpionfly LB95055(6), 95057, 95058, 95059, 95060, 95061
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Baissoptera liaoningensis n. sp.2
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"Alloraphidia obliquivenatica n. sp." = Stenoraphidia obliquivenatica2, "Liaoraphidia fornicata n. gen. n. sp." = Siboptera fornicata2, "Archeraphidia polyphlebia n. sp." = Mesoraphidia polyphlebia2, "Archeraphidia shangyuanensis n. sp." = Mesoraphidia shangyuanensis2, "Alloraphidia longistigmosa n. sp." = Mesoraphidia longistigmosa2
"Alloraphidia obliquivenatica n. sp." = Stenoraphidia obliquivenatica2 Ren 1994 snakefly Sh006, 005, 007, 008, 009, 010, 011
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Mesascalaphus yangi n. gen. n. sp.
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"Lembochrysa miniscula n. gen. n. sp." = Mesypochrysa miniscula9, "Lembochrysa polyneura n. sp." = Mesypochrysa polyneura9
"Lembochrysa miniscula n. gen. n. sp." = Mesypochrysa miniscula9 Ren and Guo 1996 green lacewing LB95010
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Lasiosmylus newi n. gen. n. sp.9
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"Kalligramma liaoningensis n. sp." = Kalligramma liaoningense9, Sophogramma eucalla n. sp.9, Sophogramma plecophlebia n. sp.9, Sophogramma papilionacea n. gen. n. sp.9
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Choromyrmeleon othneius n. gen. n. sp.9
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Oloberotha sinica n. gen. n. sp.9
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Chrysogomphus beipiaoensis n. gen. n. sp.1
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Mesocordulia boreala n. gen. n. sp.8
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Liogomphus yixianensis n. gen. n. sp.8
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Rudiaeschna limnobia n. gen. n. sp.8
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Aeschnidium heishankowensis | |
"Sinaeschnidia cancellosa n. sp." = Aeschnidium heishankowensis
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