The Vergol locality (Montbrun-les-Bains, South-East France), a candidate section for the Valanginian GSSP (Global Stratotype Section and Point), was studied in detail ammonites calcareous nannofossils. A bed-by-bed sampling quantitative approach were carried out on this expanded succession presenting continuous record of calcareous-marl alternations covering uppermost Berriasian lowermost Valan...

The Ammonoidea is a group of extinct cephalopods ideal to study evolution through deep time. The evolution of the planispiral shell and complexly folded septa in ammonoids has been thought to have increased the functional surface area of the chambers permitting enhanced metabolic functions such as: chamber emptying, rate of mineralization and increased growth rates throughout ontogeny. Using na...

The study of septal patterns in ammonoids has been centered on functional and/or constructional issues. Complexly fluted septa have been considered as complementary structures that reinforce the ammonite shell, their frilled sutures possibly manifesting the demand for strength. Ammonitic sutures display features that denote typical fractal behavior, since they can present very long perimeters r...

Jurassic and Lower Cretaceous successions of the Manin Unit Central Western Carpathians are exposed in Butkov Quarry Middle Vah Region, Slovakia. A significant part macrofauna belonging to neocomitid ammonites, formerly classified under genus Teschenites Thieuloy, 1971, occurs deposits spanning Valanginian/Hauterivian boundary. The original definition was accompanied by uncertainties taxonomic ...