Palaeontology, taxonomic revision and variability of some species of the genus Gassendiceras Bert et al., 2006 (Ammonitina, Upper Barremian) from southeastern France
Authors
Didier Bert
Laboratoire du Groupe de recherche en Paléobiologie et biostratigraphie des Ammonites (G.P.A),
Bois-Mésange, quartier St Joseph, F-04170 La Mure-Argens
Stephane Bersac
Laboratoire du Groupe de recherche en Paléobiologie et biostratigraphie des Ammonites (G.P.A),
Bois-Mésange, quartier St Joseph, F-04170 La Mure-Argens
Gerard Delanoy
Department of Earth Sciences, University of Nice-Sophia-Antipolis, Sciences Faculty,
28 avenue Valrose, F-06108 Nice Cedex 2
Leon Canut
Laboratoire du Groupe de recherche en Paléobiologie et biostratigraphie des Ammonites (G.P.A),
Bois-Mésange, quartier St Joseph, F-04170 La Mure-Argens
Keywords:
Ammonoidea, Gassendiceratinae, Upper Barremian, Southeastern France, Taxonomy, Intraspecific variability.
Abstract
Bed-by-bed sampling of twelve Barremian sections in southeastern France from pelagic basin (Vocontian Basin) to neritic platforms (Arc of Castellane, Arc of Nice and Provençal Domain) has enabled the collection of isochronous samples of the ammonite genus Gassendiceras. Three poorly known species of the Toxancyloceras vandenheckei Zone (Upper Barremian) are revised: G. alpinum, G. multicostatum and G. hoheneggeri; two new species are described (G. rebouleti nov. sp. and G. bosellii nov. sp.). The intraspecific variability of particular species was recognised. This variability is between slender peramorphic and robust paedomorphic extreme morphologies, with the presence of all intermediates.
