comment on this calibration


Lineage (NCBI): This node has no ancestors.
 node name
Apodidae     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Ksepka and Clarke, 2015
  node minimum age
51 Ma
NHMUK A5430 was collected from Bed R6 of the Røsnæs Clay Formation of Ølst, Denmark (Harrison, 1984). Bed R6 is the uppermost division of the Røsnæs Clay Formation, and is overlain by Bed L1 of the Lillebælt Clay Formation (Heilmann-Clausen et al. 1985). Magnetostratigraphic work (Heilmann-Clausen et al., 2010) demonstrates that Bed L2 of the Lillebælt Clay spans part of Chron 22r, which constrains the age of the base of the Lillebælt Clay to >49Ma. Thiede et al. (1980) assigned the upper calcareous beds of the Røsnæs Clay Formation, including R5 and R6 to nannoplankton biozones NP11 and NP12. Biostratigraphy supports correlation of the Røsnæs Clay Formation to the European mammal reference biozone MP8 (Mlíkovsky, 1996), which suggests an age >50Ma (Gradstein et al., 2004). A conservative minimum age of 51Ma is proposed, based specifically on the estimated age of the upper boundary of NP12, which is dated to 51Ma (Gradstein et al. 2012).
  node maximum age
0 Ma
None specified
 primary fossil used to date this node 
Scaniacypselus wardi, Harrison, 1984
Location relative to the calibrated node: Stem

[show fossil details]
     Locality: Ølst
     Stratum: Bed R6 of the Røsnæs Clay Formation
     Geological age: Eocene, Paleogene, Cenozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
Phylogenetic analysis of morphological data (Mayr, 2003, 2005c) and combined morphological and molecular data (Ksepka et al., 2013) places Scaniacypselus wardi closer to Apodidae than to Hemiprocnidae.
  phylogenetic reference(s)
Mayr, G. 2003. Phylogeny of early Tertiary swifts and hummingbirds (Aves: Apodiformes). Auk, 120:145-151.
Ksepka, D.T., Clarke, J.A., Nesbitt, S.J., Kulpe, F. and Grande, L. 2013. Fossil evidence of wing shape in a stem relative of swifts and hummingbirds (Aves, Pan-Apodiformes). Proceedings of the Royal Society B, 280: 20130580.
 tree image (click image for full size) 
tree image
Figure 7 from Ksepka and Clarke (2014): Phylogenetic tree showing position of Scaniacypselus wardi, illustrating the divergence calibrated by NHMUK A5430.