Icacinaceae fossil fruits from three sites of the Paris Basin (early Eocene, France): local diversity and global biogeographic implications

The Icacinaceae family have an important fossil record, mainly in the Paleogene of North America and Europe. The importance of this family in the Paleogene of the Paris Basin has been investigated recently based on two assemblages, Le Quesnoy (Houdancourt) and Rivecourt (Oise), and here we treat the Icacinaceae from three additional early Eocene sites. The Passy site reveals the presence of a new species, Iodes passiciensis Del Rio & De Franceschi, sp. nov., unique in having 25-29 areoles with no freely ending ridgelets, small pores, and rounded ridges. Two other species described previously from the Paleocene of Rivecourt were also recorded. The Grès de Belleu site also includes the first occurrence of a Palaeophytocrene Reid & Chandler in the Paris Basin and an Iodes Blume specimen without precise assignment. Lastly, in the Prémontré site only one endocarp locule cast belonging to Icacinicaryites Pigg, Manchester & DeVore was recorded and described. Using data from all five sites, the diversity of Icacinaceae in the Paris Basin is discussed and biogeographic scenarios are developed.