"Sterculia" coloradensis Leaf | Green River Formation

Nicely preserved "Sterculia"coloradensis leaf from the order Malvales

Green River Formation

In Stone Fossils Private Quarry 

Measures approx: 3.5" x 3" Matrix measures approx: 7.5"x 6.5"

Trilobed leaves that were once thought to represent the Chocolate group of the Mallow family have traditionally been identified as "Sterculia" coloradensis, but inclusion of this species in the extant genus Sterculia (and the family Malvaceae) is probably inaccurate (S. Manchester, pers. comm., 2010). This species is a common component of the FBM flora as well as in other Green River Formation localities. Today the order Malvales has about 6,000 species grouped within nine families. Most species inhabit tropical or subtropical regions, where they are widely distributed. They also have a limited distribution in temperate regions. -The Lost World of Fossil Lake, Lance Grande