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 node name
Neoptera     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations
Wolfe et al. 2016
  node minimum age
319.9 Ma
P. straeleni was discovered in Charbonnage de Monceau-Fontaine, Charleroi Coal Basin, Belgium (Brauckmann et al., 1994). The specimen was likely found in latest Marsdenian strata about 3m below the base of the Yeadonian (discussed by Brauckmann et al., 1994). The fossil bearing deposits are assigned to the late Namurian B (Marsdenian) based on the Bilinguites superbilinguis R2c2 subzone of goniatite ammonoid stratigraphy (Brauckmann et al., 1994). 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. 319.9 Ma 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 P. straeleni.
  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 
IRScNB a9885
Protoprosbole straeleni, Laurentiaux, 1952
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Charbonnage de Monceau-Fontaine
     Stratum: Charleroi Coal Basin,
     Geological age: Carboniferous, Paleozoic

  phylogenetic justification
The original description of P. straeleni as a member of Hemiptera by Laurentiaux (1952) has been rejected several times (Hennig, 1981; Nel et al., 2012b; Shcherbakov, 1995). Nel et al. (2012b) summarize the phylogenetic position of P. straeleni as being within Paraneoptera (a clade unsupported by recent molecular studies, but comprising Psocodea and Condylognatha). The cua-cup contact with CuP and the flexion or nodal line following the course of RA are both similar to those observed in extant Hemiptera (Nel et al., 2012b). However, the presence of three veins in the anal area is argued as a hemipteran autapomorphy that is lacking in P. straeleni (Nel et al., 2012b). Conservatively, this fossil species can be thus assigned to the stem group of Condylognatha, and thus crown Eumetabola and Neoptera.
  phylogenetic reference(s)
Nel, A., Prokop, J., Nel, P., Grandcolas, P., Huang, D.-Y., Roques, P., Guilbert, E., Dostál, O., Szwedo, J., 2012b. Traits and evolution of wing venation pattern in paraneopteran insects. J. Morphol. 273, 480–506
 tree image (click image for full size) 
tree image
Figure 19 from Wolfe et al. (2016).