Eocene Ginkgo leaf fossils from the Pacific Northwest

Middle Eocene lacustrine deposits in south-central British Columbia and north-central Washington state preserve two types of Ginkgo leaves. A morphotype characterized by deeply divided multiple lobes is herein described as Ginkgo dissecta sp.nov. Leaves that are either undivided or shallowly divided into bilobate symmetry are indistinguishable from foliage of extant Ginkgo biloba Linnaeus. These fossils contradict the widely held belief that only a single Ginkgo species, Ginkgo adiantoides (Unger) Heer, inhabited Cenozoic forests.Key words: British Columbia, Eocene, fossil, Ginkgo adiantoides, Ginkgo biloba, Ginkgo dissecta, McAbee, Republic, Tertiary, Washington.