2 Two Detailed Fossil March Fly Insect Green River FM Uintah County UT Eocene Age
Location: Uintah County, Utah
Weight: 1 Ounce
Dimensions: 2.1 Inches Long, 1.8 Inches Wide, 0.3 Inches Thick (Plate)
Insect One Dimensions: 0.4 Inches Long, 0.4 Inches Wide
Insect Two Dimensions: 0.4 Inches Long, 0.4 Inches Wide
The item pictured is the one you will receive.
50 million years old, Eocene age
March Fly Insect
Fossil Lake, which occupied approximately 930 square miles of southwestern Wyoming during the Eocene epoch 50 million years ago, represents an unparalleled paleontological resource. Of the original lacustrine system, roughly 500 square miles of sediment persist, with the central 230 square miles exhibiting exceptional fossil density across multiple depositional environments—deltas, beaches, springs, and both profundal and littoral zones. The lake's distinctive hydrochemistry inhibited microbial decomposition and scavenging, facilitating the gradual accumulation of finely laminated limestone strata that now contain the world's most abundant concentration of fossil fish. This geological archive preserves a comprehensive Paleogene freshwater ecosystem encompassing cyanobacteria, aquatic flora, arthropods, amphibians, reptiles, avifauna, and early mammals, including the earliest known pantolestid. The surrounding subtropical terrestrial biota is equally well-documented through rare fossils of equids, ophidians, saurians, chiropterans, and over 325 plant taxa. Systematic excavation since the 1870s has yielded thousands of exquisitely preserved specimens, establishing Fossil Lake as the preeminent record of early Cenozoic lacustrine paleoenvironments and their associated biotic communities.
