Adult morphologies of Pusozia quenstedti (Parona & Bonarelli, 1897) (Ammonoidea, Desmoceratidae) in the Albian of the South-East of France. Taxonomic implications

Abstract

Several adult specimens belonging to the genus Puzosia Bayle, 1878, were collected in the Albian of Lieuche (Alpes-Maritimes, France). Comparison with material from the condensed Albian levels of La Balme de Rencurel (Isère, France), in particular those described and figured by Jacob (1908), has highlighted a morphological link between the adult forms from Lieuche and the incomplete specimens from the condensed levels of the Lower-Middle Albian of south-eastern France and to identify them as Puzosia quenstedti (Parona & Bonarelli, 1897). These new details on the ontogenetic development of this species also allow new perspectives in the taxonomic treatment of Albian Puzosia species. A modified diagnosis of Puzosia quenstedti is proposed. The presence of Douvilleiceras sp. juv. aff. D. mammillatum (Schlotheim, 1813) in superimposed overlying levels allows assignation of a Lower Albian (Douvilleiceras mammillatum Superzone) to a basal Middle Albian age (Hoplites dentatus Zone).