2.9" Rhus Viburnoides Leaf Poison Oak 66-56 Mil Yrs Old Paleocene Raton FM Colorado

Rhus viburnoides refers to a fossil species of plant that is closely related to modern poison oak. These fossil discoveries provide crucial evidence for understanding the evolutionary history and ancient distribution of the Toxicodendron genus, which includes poison ivy, poison oak, and poison sumac. The identification of Rhus viburnoides as a fossil species within this group is based on detailed morphological comparisons of fossilized leaves, fruits, and sometimes wood with their modern counterparts.

Fossil evidence of Rhus viburnoides indicates that plants with the characteristic allergenic urushiol compounds, which cause contact dermatitis in humans, have existed for millions of years. The presence of these fossils in various geological strata, particularly from the Cenozoic Era, helps scientists reconstruct past climates and ecosystems. For instance, the discovery of Rhus viburnoides in specific ancient environments suggests conditions that were conducive to its growth, such as temperate or subtropical climates.