comment on this calibration


 node name
Cavilabiata     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Kohli et al., 2016
  node minimum age
168 Ma
The Daohugou-Biota, resting on the Jiulongshan Formation, has been dated with SHRIMP U-Pb zircon age of 168-152 Ma, giving a minimum age for Jiulongshan Formation of 168 Ma (Liu et al., 2006). There is debate about the age of the Jiulongshan Formation, as radioisotopic studies have not been congruent (Liu et al., 2012). However, because the Daohugou Formation overlies the Jiulonshan formation, we can conservatively use the age range of the former to provide a minimum age as 168 Ma for the calibrating fossil.
  node maximum age
None specified
 primary fossil used to date this node 
NIGP 148312
Juralibellula ningchengensis, Huang and Nel, 2007
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Daohugou village
     Geological age: Jurassic, Mesozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
he phylogenetic relationship of this fossil with Aeshnidae and hence Anisoptera is strongly supported by many wing venational synapomorphies (Bechly et al., 2001; Nel and Huang, 2009). These include: the presence of Rsp1 vein, RP1 and RP2 basally parallel up to the pterostigma, and RP3/4 and MA undulating.
  phylogenetic reference(s)
chly, G., Nel, A., Martínez-Declòs, X., Jarzembowski, E.A., Coram, R., Martill, D., Fleck, G., Escuillié, F., Wisshak, M.M., and Maisch, M. 2001. A revision and phylogenetic study of Mesozoic Aeshnoptera, with description of numerous new taxa (Insecta: Odonata: Anisoptera). Neue Paläontologische Abhandlungen, 4:1-219.
Nel, A. and Huang, D. 2009. First Chinese Cymatophlebiidae from the Middle Jurassic of Inner Mongolia (Odonata: Anisoptera: Aeshnoptera). Palaeodiversity, 2:199-204.
 tree image (click image for full size) 
tree image
Figure 3 from Kohli et al. (2016).