comment on this calibration

Clupeocephala

 node name
Clupeocephala     Look for this name in NCBI   Wikipedia   Animal Diversity Web
 
  recommended citations
http://palaeo-electronica.org/content/fc-1 Benton et al. 2015
 
  node minimum age
150.94 Ma
The Zandt Member of the Solnhofen Formation is constrained to the Lithacoceras eigeltingense Horizon of the Lithacoceras riedense Subzone of the Hybonoticeras hybonotum Ammonite Zone (Schweigert, 2007), indicating an earliest Tithonian age. The interpolated age estimate for the top of the Hybonoticeras hybonotum Zone is 150.94 Ma (Ogg et al., 2012a), which represents a minimum time of origin for crown Cluepocephala.
 
  node maximum age
235 Ma
A probable maximum bound on the origin of crown Clupeocephala can only be defined arbitrarily. Immediate outgroups to this clade either appear marginally later (Otocephala; see node 32) or earlier (Elopomorpha; see node 30) in the fossil record. This more-or-less simultaneous appearance of highly divergent crown teleost lineages suggests a major gap in the early history of the clade. Crown teleosts are completely absent from older marine Lagerstätten of Triassic-Middle Jurassic age, including the Zorzino Limestone (Norian; Tintori; 1998), the Posidonia Shale (Toarcian; Hauff and Hauff, 1981; Röhl et al., 2001), the Blue Lias (Sinemurian-Hettangian; Page, 2010; Forey et al., 2010), and the Oxford Clay (Callovian-Oxfordian; Hudson and Martill, 1991; Martill, 1991). However, these assemblages all yield a diversity of species that belong to the teleost stem lineage. The oldest fossils that can be recognized as stem teleosts predate these spectacular faunas, and include specimens assigned to Prohalecites from the Calcare di Perledo-Varenna and Meride Kalk in northern Italy (Tintori, 1990; Arratia and Tintori, 1999; Arratia, 2013). These horizons are interpreted as latest Ladininan in age on the basis of palynomorphs (Arratia and Tintori, 1999). Prohalecites or any other stem teleosts are completely absent from the roughly coeval Lagerstätte of Besano-Monte San Giorgio (Tintori, 1998), which otherwise yields a rich fauna of marine fishes. We therefore take the base of the Ladinian, dated approximately as 242 Ma, as an estimated maximum bound for the origin of crown Clupeocephala.
 
 primary fossil used to date this node 
 
JM SOS 2473
Leptolepides haerteisi, Arratia, 1997
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Zandt, Bavaria
     Stratum: Solnhofen Formation
     Geological age: Jurassic, Mesozoic
 
 

 
  phylogenetic justification
Leptolepides haerteisi is placed in an extinct radiation of Jurassic-Cretaceous teleosts (Orthogonikleithridae) that is resolved as the sister group of Salmonoidei plus Esocoidei in a maximum-parsimony analysis of 135 morphological characters (Arratia, 1997). Because this and subsequent analyses (e.g., Arratia, 1999, 2000; Arratia and Tischlinger, 2010) only include representatives of a single crown euteleost lineage, it is impossible to determine whether Leptolepides and other orthogonikleithrids fall within the euteleost crown or are instead stem members of the clade. Regardless of its precise placement with respect to extant euteleosts, Leptolepides haerteisi provides a minimum age for the divergence between Otocephala and Euteleostei.
 
  phylogenetic reference(s)
Arratia, G. 2000. Remarkable teleostean fishes from the Late Jurassic of southern Germany and their phylogenetic relationships. Mitteilungen aus dem Museum für Naturkunde in Berlin, Geowissenschaftliche, Reihe 3:137-179.
Arratia, G. 1997. Basal teleosts and teleostean phylogeny. Palaeo Ichthyologica, 7:1-168.
Arratia, G. and Tischlinger, H. 2010. The first record of Late Jurassic crossognathiform fishes from Europe and their phylogenetic importance for teleostean phylogeny. Fossil Record, 13:317-341.
 
 tree image (click image for full size) 
tree image
Figure 5 from Benton et al. (2014).
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