Description

Quercus sp.
Seed
Miocene
Succor Creek Flora
Succor Creek, Idaho, USA

22mm acorn on 54mm matrix.

Quercus is the genus for oak trees.  The earliest confidently-known fossils are pollen from the Late Paleocene of Austria, but by the Middle Eocene, it had spread to elsewhere in Europe, North America, and Asia.  Oaks originated in tropical forests but they continued to thrive while other trees retreated to lower latitudes as climates became drier and cooler across the Oligocene and Miocene.  Many modern species may have appeared around the time this seed was buried.