Palm fruits from the Oligocene of west coastal Peru

Two species of palms are recognized based on new collections and re-examination of carpological remains from the Oligocene of Belen, Peru: Palmocarpon bravoi Berry emend. and P. dicellaformis (Berry) comb. nov. Reflected light investigations were supplemented by micro-CT scan imagery and physical sectioning to reveal internal structure. Both species possess cylindrical peg-like protrusions on the locule casts representing germination pores of the pyrene wall. P. bravoi fruits are unilocular and relatively elongate, 12 mm long, with sub-basal pores, while those of P. dicellaformis are trilocular and 9-12 mm long with subequatorial pores. Prior identification of the trilocular fruits as capsules of Matayba (Sapindaceae) is dismissed based on the presence of germination pores. Affinities of both species are inferred to lie with the Cocosoid palms particularly close to extant Attaleinae (P. bravoi) and Bactridinae (P. dicelliformis). The Belen fruits are the best-documented occurrence of fossil Cocoseae in South America and are evidence of the group's presence before the aridification of the Pacific coast of Peru.