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 node name
Pterygota     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations
Wolfe et al. 2016
  node minimum age
319.9 Ma
The insect beds where this species was located are near Xiaheyan Village in the Qilianshan Mountains, Zhongwei County, Ningxia Huizu Autonomous Region, northwest China (Zhang et al., 2013). The insect fossil deposits are within the uppermost unit of the upper Tupo Formation (synonyms Hongtuwa or Zhongwei Formation). The presence of the ammonoids Reticuloceras reticulatum, Gastrioceras listeri and Gastrioceras montgomeryense and conodonts Declingnathodus noduliferous and Neognathodus symmetricus indicate a Namurian B/Cage (Xie et al., 2004; Yang, 1987; Yang et al., 1988; Zhang et al., 2013).The (late) Namurian-(early) Westphalian boundary is defined by the earliest occurrence of the goniatite G. subcrenatum (Waters and Davies, 2006), but lacks a precise isotopic date. Pointon et al. (2012) estimated an age of c. 319.9Ma for the base of the Westphalian (top of the Namurian, only slightly younger than the Marsdenian) based on Milankovitch cycles of sedimentation, giving a minimum age for Xiaheyan fossils.
  node maximum age
521 Ma
A soft maximum age is obtained from the oldest mandibulate, Y. dianensis, which was recovered from the Yu'anshan Formation at Xiaotan section, Yongshan, Yunnan Province, attributed to the Eoredlichia–Wutingaspis Biozone (Zhang et al., 2007). Chinese Cambrian stratigraphy has been revised substantially and the Eoredlichia –Wutingaspis Biozone is no longer recognized (Peng, 2003, 2009). However, Eoredlichia is known to co-occur with Hupeidiscus, which is diagnostic of the Hupeidiscus-Sinodiscus Biozone, which is formally recognized as the second biozone of the Nangaoan Stage of the Qiandongian Series of the Cambrian of China (Peng and Babcock,2008). The Nangaoan is the proposed third stage of the Cambrian System for the International Geologic Timescale (Peng et al., 2012a).Thus, a soft maximum constraint can be established on the age of the lower boundary of the Nangaoan, which has been dated to 521 Ma (Peng et al., 2012a; Peng and Babcock, 2008).
 primary fossil used to date this node 
BGR 9216
Delitzschala bitterfeldensis, Brauckmann and Schneider, 1996
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Bore WISABAW 1315
     Stratum: Sandersdorf Formation
     Geological age: Carboniferous, Paleozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
D. bitterfeldensis is considered a member of the family Spilapteridae, in the clade Palaeodictyopterida (Brauckmann and Schneider, 1996). Morphological characters supporting this relationship include the concave anterior wing margin and deeply bifurcate MA vein ending with two long branches (Brauckmann and Schneider, 1996; Li et al.,2013b). Other fossils of Spilapteridae have also preserved the distinctive colour patterns and long cerci observed in D. bitterfeldensis (Li et al.,2013b). Palaeodictyoptera have previously assumed to be related to extant Palaeoptera as they share the inability to fold their wings over the abdomen (a character observed in D. bitterfeldensis). However, a recent morphological phylogenetic analysis controversially recognized Palaeodictyopterida as the fossil sister group of Neoptera (Sroka et al.,2015). In this evolutionary scenario, palaeopterous wings are presumably a symplesiomorphy. Nonetheless, the position of Palaeodictyoptera suggested by Sroka et al. (2015) remains within crown Pterygota.
  phylogenetic reference(s)
Brauckmann C., Schneider J. 1996. Ein unter-karbonisches Insekt aus dem Raum Bitterfeld/Delitzsch (Pterygota, Arnsbergium, Deutschland). N. Jb. Geol. Paläont. (Monatsh.) 17–30.
Li Y., Ren D., Pecharová M., Prokop J., 2013. A new palaeodictyopterid (Insecta: Palaeodictyoptera: Spilapteridae) from the Upper Carboniferous of China supports a close relationship between insect faunas of Quilianshian (northern China) and Laurussia. Alcheringa 37, 487–495.
Sroka P., Staniczek A.H., Bechly G., 2015. Revision of the giant pterygote insect Bojophlebia prokopi Kukalová-Peck, 1985 (Hydropalaeoptera: Bojophlebiidae) from the Carboniferous of the Czech Republic, with the first cladistic analysis of fossil palaeopterous insects. J. Syst. Palaeontol. 13, 963–982.
 tree image (click image for full size) 
tree image
Figure 17 from Wolfe et al. (2016).