ParadeshayesitesParadeshayesites is an extinct genus of cephalopod belonging to the Ammonite subclass.Biostratigraphic significanceThe International [Commission on Stratigraphy] has assigned the First [Appearance Datum] of Paradeshayesites oglanlensis as the List of [Global Boundary Stratotype Sections and Points#List|defining biological marker] for the start of the Aptian Stage of the Cretaceous, ~125.0 million years ago.