A new species of freshwater Testudinoidea is described from the fossil locality of Le Quesnoy (Oise, France; Argiles à Lignites du Soissonnais, Lower Eocene, Ypresian, MP7). This taxon is the oldest representative of Ptychogasteridae known from Europe. This species is compared to the American representatives of the genus Echmatemys Hay, 1906, to three Ptychogasteridae from the Geiseltal Formation (Eocene, Germany; Geiselemys ptychogastroides [Hummel, 1935], “Geoemyda” saxonica Hummel, 1935 and Hummelemys ambigua Hervet, 2004b), and to representatives of the Ptychogaster complex and to Clemmydopsis Boda, 1927. The phylogenetic relationships of this new taxon and of the other European Ptychogasteridae are studied.