Presence of the foraminifer Chapmanina gassinensis Silvestri, 1931, in the Eocene (Lutetian) of the Grignon "falunière" (Yvelines, Paris Basin). The genus Chapmanina, its species and world distribution

Chapmanina gassinensis (foraminifer) has been observed as it seems for the first time in the Lutetian of the “falunière” of Grignon (Yvelines, southwestern Paris Basin). It is widespread in the Eocene of western Europe, also present in the Tethysian domain l.s. and even across the Atlantic. In the Oligocene, it becomes very rare and has been only found in some places of Mediterranean Europe and disappears in the Miocene. The Paris Basin seems to be its northernmost occurrence.