I collected these on Saturday in western Colorado. They are from the Eocene Green River Formation. Here is a link that tells a bit more about them. My guess Diptera.
http://www.coloradomtn.edu/campus_rfl/staff_rfl/kohls/eocene.html
Locarion: From I-70 in western Colorado take the Rifle exit and go 19.5 miles north on Rt 13 toward Meeker. At a deserted truck stop(red buildings) go west on Piceance Creek Rd(left). Go 1.9 miles and you will see a good sized area to turn off, This is where I found them. There are a lot of places to collect on the right side of the road- go a bit further and you can see lots of outcrops but difficult to park(BLM land). I have see other groups collect here.
These are difficult to find. I spent 2 hours splitting shale before I found these two. Notice the delicate winged membranes preserved. Also a lot of plant material. The last photo is of a delicate leaf.
You will be splitting the lt brown Green River shale. The gray shale is devoid of fossils. Recommend hand lens. eye protection and a rock hammer. A good chisel is a must for splitting the shale. A lot of hard work but insects are always rare finds.
George
http://www.coloradomtn.edu/campus_rfl/staff_rfl/kohls/eocene.html
Locarion: From I-70 in western Colorado take the Rifle exit and go 19.5 miles north on Rt 13 toward Meeker. At a deserted truck stop(red buildings) go west on Piceance Creek Rd(left). Go 1.9 miles and you will see a good sized area to turn off, This is where I found them. There are a lot of places to collect on the right side of the road- go a bit further and you can see lots of outcrops but difficult to park(BLM land). I have see other groups collect here.
These are difficult to find. I spent 2 hours splitting shale before I found these two. Notice the delicate winged membranes preserved. Also a lot of plant material. The last photo is of a delicate leaf.
You will be splitting the lt brown Green River shale. The gray shale is devoid of fossils. Recommend hand lens. eye protection and a rock hammer. A good chisel is a must for splitting the shale. A lot of hard work but insects are always rare finds.
George
