Astronium truncatum
Early Eocene
Green River Formation – Parachute Creek Member
Rio Blanco County, CO USA.

Big 28mm flower on 54mm matrix

Astronium is a plant genus in the Family Anacardiaceae which includes a variety of modern trees such as mango, cashew, pistachio, and pepper as well as poison ivy and poison oak.  Fossil flowers referred to Astronium date back to at least the Early Eocene.

This specimen represents one of the earliest occurrences of the genus.