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The Green River Formation is one of the most well-known fossil sites in the world, occupying present-day Colorado, Utah and Wyoming. This Lagerstätte has been noted for its well-preserved fish fossils, as well as numerous invertebrates, plants, and sometimes even reptiles and birds. Green River fossils are Eocene-aged, at 53.5 to 48.5 million years old. Thankfully, not only are Green River fossils attractive, they also remain affordable to the casual collector. Allow me to present my humble collection. Crocodile tooth Borealosuchus sp. Southwest Wyoming Water bird tracks (possibly sandpipers or plovers) Presbyorniformipes feduccii Vernal, Utah Bird feather Aves indet. Southwest Wyoming Crane flies & Mosquitoes Pronophlebia rediviva & Culex sp. Parachute Creek Member; Douglas Pass, Colorado

Hi. Good afternoon to everyone! In one lot, the seller is selling these two fossil fish. Please, then I have two questions: 01 - Any makeup or paint here? It's real? 02 - Which one is Knightia eocaena and which one is Knightia alta? Or are the two of a specie? Thanks for all the comments! Fish 01 Fish 02

I just received this multi fish plate in the mail yesterday. It was a bargain from our favorite auction site. Not quite sure if it is a plate of Gosiutichthys parvus, or Knightia eocaena. The description listed them as small Knightia sp. (eocaena, most likely), but I know many of the Green River fish on the auction site are mis-identified. The individual fish look like Gosiutichthys to me. The largest one on the plate is about 2.25 inches. They seem to have the upward mouth gape, and the dorsal fins appear to me to be a bit more anterior of the center of the fish. I haven't gone as far as counting the fin rays yet, but am able to if necessary, (which is looking more likely ). Any thougths appreciated.

I have difficulties to find out what this small fish (1.8" or 4,5cm) from the Eocene GRF is. A baby Priscacara or Cockerellites? Or is it a Hypsiprisca hypsacantha? Or one of these so far (?) undescribed Priscacara species? The tail fin seems to be very, very slightly forked (almost round) and the Praeoperculum bears some spines. So I would guess Hypsiprisca hypsacantha, but I am not sure. Who can help? Thanks Thomas

Anyone know of some good papers or books for identifying the species on GRF leaves? Mainly looking for leaf info, but insect info is welcome too. Nathan

The Trip That Nearly Didn't Start (Lengthy image-intensive trip report follows) Tammy and I had planned a fossil hunting trip to Wyoming for the third week of September to redeem our day of digging (splitting rock) at the Green River Formation quarry that @sseth had earlier so generously offered up as a prize on an auction to benefit TFF. We had our airfares, a rental car reserved, and a series of hotels booked across the state ready for a monumental fossil hunting trip. The one small problem was the not so small storm named Hurricane Irma that tore through the northern Caribbean and had its sights set on the Florida and being wider than the peninsula, no Floridian was going to miss the effects of this storm. Earlier in the week the forecast had the centerline of the cone of probability for the track of the storm hitting Miami and traveling up the eastern coast where Boca Raton sat squarely in the cross-hairs. I guess that if you are going to be in the path of some major destruction it is better to be the target early in the week rather that toward the end when the storm is at our doorstep. Thankfully (for us, but not so for those in the Lower Keys and Southwest Florida), the storm's turn to the north was delayed and though we were now on the stronger NE quadrant of the storm, the eye was significantly far away to the west that we escaped the strongest of winds. The storm unleashed squadrons of tornadoes and micro-bursts which had us ducking into our safe room for cover. During the storm unidirectional winds first blew from the east and then from the south as the storm passed us to the west but the tornadic winds were something else as the trees started whipping around in all directions quite violently. Luckily for us, the house survived with no structural damage. The newer more sturdy pool cage that replaced the original one that Wilma had crumpled and stuffed into the pool back in 2005 (shockingly) did not even lose a single screen panel. The damage on our property was limited to toppled trees and broken limbs and branches. We lost power even before the eye wall had made first landfall in the Florida Keys. As soon as it was safe to go outside, we started the portable generator and ran extension cords throughout the house to keep refrigerator, freezer and a box fan and a few lights powered. We've cooked on our outdoor grill and Coleman camp stove in previous power outages caused by the rash of hurricanes in 2004/05 and so we were well prepared and never at risk of starvation (we actually ate rather well). While Wilma had run over the house in late October, 2005 when the temperatures had cooled somewhat from the hot muggy Florida summer, we were not so lucky this time. Outdoor temps in the low 90's were soon matched by the 88 degrees inside which made sleeping difficult (even with a fan). We spent the days cutting up the downed foliage and stacking it into many piles along the street in back of the house as well as a towering mount in the cul-de-sac in front (which is still growing in size to this day and is due to be cleared by FEMA sometime in the next 2-3 weeks). Taking frequent breaks inside to lay down on the floor in front of the fan to avoid all-out heat exhaustion, both Tammy and I worked to clear the property as much as we could and monitor the progress of power restoration in our county. Over 70% of homes and businesses were left in the dark after Irma but Florida Power & Light had learned a few things after performing poorly in the 2004/05 hurricane seasons. They had staged a bunch of replacement parts and crews fresh from working in Houston were in the state working to get the grid back online. We couldn't leave on our trip unless we got power back and we watched the percentage of customers without power slowly but steadily decrease until one evening our power flickered and within a few minutes was restored for good. I had been waiting till the last possible minute to cancel my plans and try to get refunds for the reservations we'd made for this trip. I was tired of a week of hot sweaty yard work clearing debris and I was ready for some cooler Wyoming temps.

Thought I would share this here as well as in Blake's post. You can stop by the Coliseum show in Denver and see it in person at (FossildudeCo ) Blake's booth. @FossilDudeCO Icaronycteris Index, found at our American Fossil quarry in August, 2017! Icaronycteris Index is one of the oldest bat species on the planet. It lived some 51 million years ago in the Eocene epoch in Wyoming. Icaronycteris was a primitive bat, emerging very early in the age of mammals. Modern bats have only a single claw on their first digit, but Icaronycteris also had another one on the second digit. Icaronycteris also lacked a uropatagium, the flap of skin in between the legs of modern bats that also includes the tail. It has a long tail, a carryover in its evolution from a land dwelling mammal. Icaronycteris also had a less rigid skeletal structure. Finally even though Icaronycteris was an insectivore, it had a full set of teeth that were relatively unspecialized beyond the basic mammalian form. Later bats would develop more specialized teeth that were also fewer in number than Icaronycteris had. It was discovered in our quarry in August 2017 and has been prepped to perfection under the microscope. It has a great deal of soft tissue preservation including muscle and membrane on the right wing, tendons, and even cartilage connecting the sternum to the ribs. It is an amazing specimen, right down to the claws on its feet. Enjoy Seth

Hi all, I saw this Diplomystus online for sale. I was surprised by the prize: 20$! But then I started to get a little suspicious. Though most fakes are mosasaurs and keichousaurs, I heard that fossil fish from the Green River formation are often re-painted so that they look more splendid. Though I am pretty sure that this specimen here was originally 100% real, I think that it might have been painted on. Is my suspicion right, or is this one 100% natural? Here is the info they gave: What do you think? Thanks, Max

Hi everyone! I am totally new at collecting fossils. My family and I went to a place south of Vernal and dug in the Green River Formation and found several leaves and insects. My question is do I need to put something over them to protect them? I have read about duco cement for bones, but I didn't read anything for leaves. I am assuming that the insects found in the same formation would be preserved the same way. I included pictures of some of the insects we found. Any advice will be greatly appreciated! Anthony

I just couldn't resist purchasing this Knightia, from the Green River Formation in Wyoming from a local craigslist seller. Yes I do troll craigslist a lot looking for all the coolest gadgetry. Well the lady I bought it from said it was gifted to her and that she had no clue what it was and didn't want it. She sold it to me for $10. I plan on taking a trip to the Green River Formation but just in case I don't make it out I decided to get this 7" beauty.

Here are copies of images that Kris posted in the "Auction prep" topic. The slab he is prepping contains this large plant fragment. I have scanned Grande's text looking for a match, but have had no success. Does anyone have a clue as to a possible donor of the fragment? Also check out Kris' interesting prep series on this Notogoneus specimen.