Manchester, Steven R. , Dillhoff, Richard M. .
Fagus (Fagaceae) fruits and foilage from the Middle Eocene of Pacific Northwestern North America.
Fruits and leaves from the Middle Eocene of McAbee, British Columbia and Republic, Washington provide an earlier record for the genus Fagus than previously accepted for this member of the Fagaceae. The fruits consist of pedicellate spiny 4-valved cupules, and trigonal nuts. The leaves are borne alternately on the twigs, and are ovate to elliptic with craspedodromous secondary veins and simple teeth distributed one per secondary vein. The shale preserving these megafossils also contains dispersed pollen with morphology and ornamentation diagnostic of Fagus. Previously, the oldest Fagus occurrences confirmed by fruits were early Oligocene (ca 32 MA). The recognition of Middle Eocene (ca 50 MA) representatives helps to reduce the disparity between molecular evidence favoring Fagus as a primitive genus within Fagaceae, and fossil evidence, which indicated older occurrences of Castanea and Quercus than Fagus.
1 - University of Florida, Department of Natural History, Florida Museum of Natural History, P.O. Box 117800, Gainesville, Florida, 32611-7800, USA
2 - Evolving Earth Foundation, PO Box 2090, Issaquah, Washington, 98027
Presentation Type: Paper
Location: Maybird (Cliff Lodge)
Date: Monday, August 2nd, 2004
Time: 10:45 AM