Southwest Wyoming’s Green River Formation has preserved spectacular, detailed, and complete fish fossils from the Eocene Epoch of approximately 50 million years ago. Bibionids (March Flies and Lovebugs) have the most extensive fossil record of any dipteran (fly) family. Fossil bibionids are known from the Jurassic, while some forms from the early part of the Upper Cretaceous look like modern species. Bibionid flies are known among insect fossils from the Tertiary period. This beautiful framed piece of natural history contains a March Fly, displayed in an elegantly designed shadow box.