Paleoochna tiffneyigen. et sp. nov. (Ochnaceae) from the Late Paleocene Almont/Beicegel Creek Flora, North Dakota, USA

Abstract

Premise of research. Paleoochna tiffneyi gen. et sp. nov. is described from late Paleocene fossil fruits from Almont (Morton County) and Beicegel Creek (McKenzie County), North Dakota. On the basis of distinctive anatomical and morphological features, these fruits demonstrate strong taxonomic affinities to Ochna and other members of the family Ochnaceae but are distinct at the generic level.Methodology. Fossil fruits were studied with a combination of transmitted and reflected light microscopy from fractured surfaces and with scanning electron microscopy. Extant fruits were sectioned by freehand sectioning with a razor blade and studied with reflected and transmitted light microscopy.Pivotal results. The study documents the first known occurrence of Ochnaceae fruits in the fossil record. They occur as late Paleocene specimens from the Williston Basin of the Western Interior of North America. Specimens are anatomically preserved and provide critical morphological details of systematic value. Like many of t...