Le dimorphisme chez Perisphinctes (Properisphinctes) cf. bernensis de Loriol (Oxfordien inférieur, région de Cracovie, Pologne)

Dimorphism in Perisphinctes (Properisphinctes) cf. bernensis de Loriol (Lower Oxfordian, vicinities of Krakow, Poland) . A sample of ammonites belonging to Perisphinctes (Properisphinctes) cf. bernensis de Loriol 1898 has been found in the Lower Oxfordian (Mariae Zone) in the vicinity of Krakow, South of Poland. Analysis of that population allows us to show that a dimorphism macroconch/microconch is present. This species, already known in Europe, quite only with nuclei, clarifies our knowledge of the Lower Oxfordian Perisphinctids.