Denaea Pruvost, 1922

Ginter, Michał, Duffin, Christopher J., Dean, Mark T. & Korn, Dieter, 2015, Late Viséan pelagic chondrichthyans from northern Europe, Acta Palaeontologica Polonica 60 (4), pp. 899-922 : 908-909

Genus Denaea Pruvost, 1922

Type species: Denaea fournieri Pruvost, 1922 , early Viséan , Denée, Belgium .

Remarks.—Since the establishment of the name Denaea ( D. fournieri ) by Pruvost (1922) for the articulated specimens of sharks from the Viséan of Denée, Belgium, several tooth-based species from all over the world have been attributed to this genus. These are as follows: Denaea meccaensis Williams, 1985 , D. decora Ivanov, 1999 , D. wangi Wang, Jin, and Wang, 2004 , D. saltsmani Ginter and Hansen, 2010 , and D. williamsi Ginter and Hansen, 2010 . D. meccaensis and D. decora were subsequently removed to Stethacanthulus Zangerl, 1990 , based on the shared very special form of base. All of the species that remain in Denaea are characterised by cladodont crowns possessing delicate cusps and thin bases with rather weakly developed articulation devices.

It appears, however, that the teeth of two articulated falcatids from the Serpukhovian of Bear Gulch in Montana, USA ( Damocles and Falcatus ) closely examined by MG in 2003, are very similar to those of Denaea . One might even say that the five-cusped teeth of D. fournieri and the teeth of those falcatids are indistinguishable when seen from the labial side (which in most cases is the only visible surface of the tooth exposed on the matrix surface). Because the teeth of D. fournieri are poorly preserved and appear to be natural casts of original elements, they cannot be extracted chemically and observed from all sides. The teeth of Falcatus and Damocles have not, so far, been extracted from the enclosing matrix either, but in this case such a possibility, although technically challenging because of the small size of the teeth, probably exists. This being the case, it is difficult to determine which of the tooth-based putative species of Denaea or other Denaea -like isolated shark teeth really belong to this genus and which, perhaps, represent Falcatus or Damocles . There are several other taxonomic problems concerning Denaea , but they will be discussed in the sections dedicated to particular species.