comment on this calibration

Oryzias – Cichlidae

 node name
Oryzias – Cichlidae     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Benton et al. 2015
  node minimum age
49.11 Ma
The age of the fish-bearing horizons of the ‘Calcari nummulitici’ at Bolca can be tightly constrained on the basis of biostratigraphy. Medizza (1975) assigned these deposits to the Discoaster sublodensis Zone (NP 14) on the basis of calcareous nannoplankton, while the larger foraminifera reported by Papazzoni and Trevisani (2006) place the unit within SBZ 11. NP 14 and SBZ 11 overlap narrowly in the late Ypresian, and the age of the fish beds at Bolca can be approximately correlated with the base of NP 14, which is dated as 49.11 Ma (Anthonissen and Ogg, 2012). We accept this date as a fossil-based minimum for the last common ancestor of Atherinomorpha and Cichlidae.
  node maximum age
130.8 Ma
Given that the anatomy of Rhamphexocoetus suggests that this genus occupies a relatively nested position within crown Atherinomorpha, is it probable that the minimum age for the Atherinomorpha – Cichlidae divergence given here is a substantial underestimate. We therefore suggest the use of a generous soft maximum bound. Percomorphs, and acanthomorphs more generally, are unknown from a series of fish faunas of mid-late Early Cretaceous age that represent a range of depositional settings from fully marine to lacustrine: the Gault Clay of England (Albian; Gale and Owen, 2010; Forey and Longbottom, 2010; Nolf, 2010), Helgoland in Germany (Aptian; Taverne, 1981b), the Crato Formation of Brazil (Martill, 1993; early interpretations of Araripichthys as a lampridiform have been decisively rejected by Patterson, 1993a and Maisey and Moody, 2001), and the Coquiero Seco Formation of Brazil (Gallo and Cohelo, 2008). The oldest of these deposits, the Coquiero Seco Formation of Brazil, yields the oldest putative representative of Eurypterygii, (the clade containing Aulopiformes, Myctophiformes, and Acanthomorpha), and provides the basis for our estimated maximum age divergence between Tetraodontiformes and Ovalentaria. The Barremian is dated to approximately 130.8-126.3 Ma (Ogg et al., 2012b); we derive our soft maximum from the oldest limit.
 primary fossil used to date this node 
MGUP 8866
Rhamphexocoetus volans, Bannikov et al. 1985
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Bolca
     Stratum: 'Calcari nummulitici’
     Geological age: Eocene, Paleogene, Cenozoic

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  phylogenetic justification
Rhamphexocoetus has not been included in a formal cladistic analysis. However, it presents a series of characters that are interpreted as synapomorphies of successively more restrictive clades within Atherinomorpha. Rhamphexocoetus can be placed within Beloniformes on the basis of its caudal fin (Rosen and Parenti, 1981), which has an expanded ventral lobe that contains more principal fin-rays than the dorsal lobe (Bannikov et al., 1985). The position of this genus can be further restricted to Exocetoidei, based on the presence of a greatly enlongated dentary (Rosen and Parenti, 1981). This feature is apparent at some point of the life history of most beloniforms, and is retained in adults as a ‘halfbeak’ condition comparable to that of Rhamphexocoetus in species traditionally assigned to Hemiramphidae, which appears to be paraphyletic (Lovejoy et al., 2004). Among exocetoids, enlarged pectoral and pelvic fins of the kind found in Rhamphexocoetus are characteristic of Exocetidae (flying fishes).
  phylogenetic reference(s)
Rosen, D.E. and Parenti, L.R. 1981. Relationships of Oryzias and the groups of atherinomorph fishes. American Museum Novitates, 2719:1-25.
 tree image (click image for full size) 
tree image
Figure 6 from Benton et al. (2014).