comment on this calibration


 node name
Anura     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Benton et al. 2015
  node minimum age
165.3 Ma
The Forest Marble Formation has long been assigned to the Late Bathonian, dated as 166.5-166.1 Ma ± 1.2 Ma (Gradstein et al., 2012, pp. 765, 777), so giving an age of 165.3 Ma as the minimum constraint.
  node maximum age
201.5 Ma
The soft maximum constraint can be set as equivalent to the base of the Jurassic, allowing for finds of various stem anurans and other small tetrapods from several continents, but as yet no crown taxa, and so 201.3 Ma ± 0.2 Ma, so 201.5 Ma.
 primary fossil used to date this node 
NHMUK R11700
Eodiscoglossus oxoniensis , Evans et al., 1990
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Forest Marble Formation
     Geological age: Bathonian, Middle Jurassic, Jurassic, Mesozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
Eodiscoglossus is identified as a member of crown Discoglossidae on the basis of two apomorphies in combination, the possession of opisthocoelous vertebrae together with an ilium bearing a dorsal crest (Evans et al., 1990; Ruta and Coates, 2007).
  phylogenetic reference(s)
Ruta M., and Coates M.I. 2007. Dates, nodes and character conflict: addressing the lissamphibian origin problem. Journal of Systematic Palaeontology, 5:69–122.
Evans, S.E., Milner, A.R., and Mussett, F. 1990. A discoglossid frog (Amphibia: Anura) from the Middle Jurassic of England. Palaeontology, 33:299-311.
 tree image (click image for full size) 
tree image
Figure 7 from Benton et al. (2015).