comment on this calibration


 node name
Palaeognathae     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Benton et al. 2015
  node minimum age
56.8 Ma
Lithornis celetius comes from the Fort Union Formation (early Tiffanian) of Montana and Wyoming, USA (Houde, 1988). The Tiffanian is equivalent to the middle to late Paleocene, and dated as 60.2-56.8 Ma (Secord, 2008).
  node maximum age
86.8 Ma
The soft maximum constraint is the same as for Neognathae (node 54), equivalent to the age of the Niobrara Chalk Formation, dated as Santonian (86.3–83.6 Ma ± 0.5 Myr), and so 86.8 Ma. Various flightless birds have been noted from the Maastrichtian, but none is convincingly palaeognath.
 primary fossil used to date this node 
USNM 290554
Lithornis celetius, Houde, 1988
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Fort Union Formation
     Geological age: Paleocene, Paleogene, Cenozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
Lithornis celetius is a member of clade Lithornithidae, which is in turn a member of the Palaeognathae, on the basis of numerous morphological apomorphies (Houde and Olson, 1981; Houde, 1988; Mayr, 2005; Leonard et al., 2005).
  phylogenetic reference(s)
Houde, P.W. 1988. Palaeognathous birds from the early Tertiary of the Northern Hemisphere. Publications of the Nuttall Ornithological Club, 22:1–148.
Leonard, L.M. Dyke, G.J., and Van Tuinen, M. 2005. A new specimen of the fossil palaeognath Lithornis from the Lower Eocene of Denmark. American Museum Novitates, 3491:1-11.
Houde, P.W. and Olson, S.L. 1981. Palaeognathous carinate birds from the Early Tertiary of North America. Science, 214:1236–1237.
Mayr, G. 2005. The Paleogene fossil record of birds in Europe. Biological Reviews, 80:515–542.
 tree image (click image for full size) 
tree image
Figure 9 from Benton et al. (2015).