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Title: Neogene Corylopsis seeds from eastern Tennessee

A new fossil species ofCorylopsis(Hamamelidaceae),C. griseaQuirk & Hermsen sp. nov, based on seeds from the early Pliocene Gray Fossil Site (GFS), eastern Tennessee, USA, is described. The assignment of the seeds to Hamamelidaceae, subfamily Hamamelidoideae, is based on the overall size of the seeds, smooth testa, lack of a seed wing, and the presence of a terminal hilar scar. The assignment to the genusCorylopsisis based on seed size as well as the presence of a hilar facet, in addition to the hilar scar. AlthoughCorylopsispersists only in East Asia today, its fossil record indicates that the genus was widespread across the Northern Hemisphere in the past. Prior to its discovery at GFS,Corylopsiswas only known from the Paleogene in North America. The presence ofC. griseaat GFS extends the fossil record ofCorylopsisin North America to the Neogene and reinforces the interpretation of GFS as a forested refugium that provided a relatively moist, equable environment where subtropical to warm temperate plants could persist during a time of cooling and drying in the continental interior of North America. Its presence provides additional evidence for the biogeographic connection between the GFS paleoflora and the modern flora of eastern Asia.

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Journal of Systematics and Evolution
Page Range / eLocation ID:
p. 611-621
Medium: X
Sponsoring Org:
National Science Foundation
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