A Paleocene occurrence of cornelian cherries Cornus subg. Cornus in the land-mammal site of Berru (Paris Basin, France)

Abstract

Cornus subgenus Cornus, also called cornelian cherries, is a relatively ancient clade of dogwoods with a complex biogeographic history. Their fossil record attests to a distribution in North America during the Late Cretaceous and Paleocene, whereas the earliest fossil record in Europe is dated as early as the Eocene. Here, we describe a new occurrence of cornelian cherries based on permineralized endocarps from the late Paleocene (ca. 58 Ma) land-mammal locality of Berru, in Northwest France. The 48 studied specimens possess characteristic cornelian cherry endocarp morphology with locules associated with a dorsal germination valve, no central vascularization, and the presence of numerous secretory cavities in the endocarp wall. In addition, the presence of (three)-four locules and a large apical depression strongly suggest affinities with the early Eocene species Cornus multilocularis from the London Clay Formation. This new occurrence expands the stratigraphic range of the species by approximately four to six million years and is the first unequivocal evidence of cornelian cherries in Europe during the Paleocene. The biogeographical history of cornelian cherries remains complex to explore because of its ancient distribution in the Cretaceous and a geographically and stratigraphically patchy Cenozoic record.