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 node name
Penicillata     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations
Wolfe et al. 2016
  node minimum age
129.41 Ma
E. jezzinensis was discovered in amber from the Jouar Ess-Souss locality,in the Jezzine area, South Lebanon (Azar et al., 2010). Previous work suggested a Neocomian (Valanginian-Hauterivian) age for the Jezzine area (Azar et al., 2010). However, Lebanese stratigraphy has recently been revised; the Jouar Ess-Souss locality is now recognized as part of the lowermost interval of the Grès du Liban (Maksoud et al., in press). The lower interval lies below a shale layer bearing the echinoid fossil Heteraster oblongus, and below a pisolitic interval bearing charyophyte fossils (Maksoud et al., in press). The charyophyte layer is associated to the Cruciata-Paucibracteatus Zone of Martín-Closas et al.(2009) in the late Barremian-early Aptian, but this layer is also older than the Banc de Mrejatt subunit within Lebanon, thus Jezzine amber is older than the Ba2 layer in Fig. 6 of Maksoud et al. (in press). Jezzine amber is therefore no younger than early Barremian. The upper boundary of the early Barremian is proposed to be the first appearance of the ammonite Ancyloceras vandenheckii (Ogg et al., 2012a).Cyclostratigraphy dates the A. vandenheckii Zone beginning at 129.41Ma (Ogg et al., 2012a), providing a minimum age for Jezzine Lebanese amber 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 
MNHNFr JS 231/1
Electroxenus jezzinensis, Nguyen Duy-Jacquemin and Azar, 2004
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Jouar Ess-Souss
     Geological age: Cretaceous, Mesozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
Cretaceous amber penicillates are readily assigned to two of the three extant families, Polyxenidae and Synxenidae (Nguyen Duy-Jacquemin and Azar, 2004; classification of Penicillata following Short in Enghoff et al., 2015). E. jezzinensis preserves diagnostic characters of Polyxenidae such as lateral extensions of the gnathochilarial palps. Membership in an extant family indicates status as crown Penicillata.
  phylogenetic reference(s)
Nguyen Duy-Jacquemin, M.N., Azar, D., 2004. The oldest records of Polyxenida (Myriapoda, Diplopoda): new discoveries from the Cretaceous ambers of Lebanon and France. Geodiversitas 26, 631–641
 tree image (click image for full size) 
tree image
Figure 8 from Wolfe et al. (2016).