Green River Formation Cricket and Cranefly Insect Fossils

Description: The Green River Formation deposits of Wyoming, Colorado, and Utah are best known for their immaculately-preserved fish, but other examples are known as well, as this specimen attests. This is an example of association plaque of a pair of craneflies, and a very detailed cricket. The cricket is most likely Pronemobius sp, possibly P. smithii, and shows that there has been little change in these insects over the past 45 million years or so. The presence of an ovipositor shows this one to be a female. The craneflies are members of the Limoniidae, a family typically smaller than the Tipulidae. This is a fine association plaque sure to become a prized addition to any Green River fossil collection.