Eocene Green River Celtis P-PCM-16-039

Celtis mccoshii
Green River Formation
Parachute Creek Member
Middle Eocene
Uintah County, Utah

This is an excellent example of this uncommon fossil leaf.  It is a complete leaf with rachis.  C. mccoshii is most similar to the foliage of the living species C. sinensis from China where it is widely distributed in temperate to subtropical floras. The living species shows all gradations from dentate to nearly entire leaves, and from incipient to complete acrodromy in common with the fossil leaves. This genus is one of the rarer fossils in the Eocene flora and was probably not abundant near the Eocene lakes.