Fruits of Icacinaceae Miers from the Palaeocene of the Paris Basin (Oise, France)

Abstract

ABSTRACTIcacinaceae Miers are a family of trees, shrubs, and lianas with a current pantropical distribution. The family is well known in the fossil record, especially from the Palaeogene of Europe and North America, with the modern genus Iodes being particularly well represented. Here, we describe five new species of Iodes based on fossil endocarps with horn-like protrusions from the late Palaeocene Rivecourt deposits (Oise, France). Moreover, we propose a new combination for Iodes israelii Soudry & Gregor, as Icacinicarytes israelii (Soudry & Gregor) Del Rio, Thomas & De Franceschi, because it lacks the diagnostic morphological and anatomical characters of the genus Iodes. The significance of papillae, which has been emphasised in the literature, is discussed in light of new data, and a more standardised system of terminology is proposed. Given that, among modern members of Iodes, horn-like protrusions are only known from Asian species; the fossils described here suggest an affinity between the late Palaeocene flora of Europe and the modern flora of Asia. Finally, this study represents the first detailed investigation of Icacinaceae from the Paris Basin, where palaeocarpology remains understudied.