Nouvelle description d’<i>Halecopsis insignis</i> de l’Éocène marin de l’Europe et les relations de ce taxon avec les Gonorynchiformes (Teleostei, Ostariophysi)
New description of dagger Halecopsis insignis from marine Eocene of Europe and relationships of this taxa with the Gonorynchiformes (Teleostei, Ostariophysi).The osteology of dagger Halecopsis insignis from the marine Eocene of Europe is briefly revised. The frontals are elongated and narrow at the preorbital level. The skull is latero-parietal. The mesethmoid is small and longer than broad. The lateral ethmoids are reduced. The pleurosphenoids are small and there is no orbitosphenoid. The lower jaw is short and the quadrate and the ventral branch of the preopercle very long. There are only four infraorbitals, all possessing a well developed membranodermic component. The supratemporal is strongly reduced. The extrascapular sensory commissure is enclosed in the parietals and passes also in a thin groove on the supraoccipital. The osteological characters allow to confirm that H. insignis belongs to the suborder Gonorynchoidei and to propose that it is phylogenetically lying between the family dagger Apulichthyidae, where the lateral ethmoid remains large, and the other families of this suborder, in which the membranodermic component of the infraorbitals is already lost
