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  1. Paul R.

    Fossil Leaf ID Needed

    Looking to ID this Green River fossil leaf if anyone has an ideas?
  2. Back in about 1992 or 93and for many years later and still to this day I took the whole family fossil hunting. I always made it a priority to take the family on a fossil vacation. I use to do 7 out of state trips for fossil hunting every year with one of those for the family and always in the last week of june or first week of July. Always had to wait for the kids to get out of school. Used to do trips that last up to 3 weeks. Ha! Now a 4 or 5 day trip is about all I can do. The misses doesn't go with me nowadays but I cant help it, I need to get out even if I cant do much because of this stroke. Ive gone on 2 fossil hunting trips already this year and still have 2 more to go. One to the Fox Hills Formation in South Dakota for more of those super nice and high quality ammonites and then my last one to Washington to get more crab concretions and to aquire more of those rare and most beautiful agitized Aturia!!! I used to keep everything but nowadays I only want quality and to grow the collection. Trimmin down some fish slabs Abssolutely LOVE this place!!! This creek changed paleo history!!! Was told that there would be a dusting of snow and a bit chilly. It got down to -12 degrees and got 4 inches of snow that buried everything!!! and yeah, we camped in that weather. I didnt see it then but now I can see that I was one of the tuffest dudes alive!!!! This was after the -12 degree night and I had to trim all the fish slabs. once in the truck with the heater on my fingers and toes were numb and then came that god awfull stinging when they thawed out. Lots of pain but came home with lots of fish! This is back when I thought split fish were cool. Not so anymore. Just too spoiled now but sure had a heck of alot of fun back in the day!
  3. Well,, it was just a couple of weeks ago when I was out on a fishing trip to the Green River Formation. We were invited back to the almost unknown 'Phareodus' layers!!! Very tuff layers for sure. We had to use special chisles for these layers along with the normal thin shims used for the 18 inch layers. We didnt end up with very many Phare's, only 2 but the boys did get some purty good B-Grade Phare's!!! What we did find was quite a few small diplo's and small Mio's in some very very nice high quality preservation. The one thing was,,, just how many small good preservation Mio's does one see? These are almost rare. What struck me also was the difference in the layers here! From one layer to the next can be completely different! Some of it was super nasty rock and had travertine on it. You find a fish in this travertine you simply toss it aside. That hurt! When the sun went away we had to go dig the 'mini' layers. The mini layers are very much like the split fish layers but you can get some really good hard layers there and you can also find some big fish there too along with the 1000's of little Knightia's. But the sun came back and again we dug the Phare layer. The boys also did some night fishing with lights in the famous 18 inch layers but only lasted about 3 hours. Still, some nice little prisci's for their efforts. It was also very cold! First morning was 32 dgrees. Tons of wind too and the second day destroyed out tent!!!!! Im gettin old and can do without the cold and wind, but for those of who know, after almost 14 months with this stroke I was for the first time able to actually do some work and for some hours. Quite happy to say the least about that!!! and even though I payed for that the next day, for me, it was Fantastic. And today, just one day after getting back I was able to unload almost all the fish, get them squared up with a square and pencil and now having a very deserved whisky and writing this! Wooooooooop Woooooooop!!!! I will pay for this tomorrow but I dont care. Ive always love getting out and fossil hunting and camping and its now finally gettting a tad bit easier. Here is my little set up before it got desroyed the next day!!! Here is a large Phareodus with some of the head missing from the 'mini' layers. The very first rock my middle son lifted. This fish is upside down. Had to build a wind block so we could have a fire for cooking baked taters with onion garlic and a slice of bacon. Makes for one heck of a baked tater!!! and some New Yorks too!!! The boys working the famous 18 inch layer. You can see in the lower left of this photo the small pad of the unknown Phareodus layer. Here is a small but very high quality Mioplosis from one of the 'Phareodus' layers! Im super excited to get these!!! To say the least!!! This fish, Diplomystus is one of the most awesome ive seen. Just fatter than a pig!!! Sad to have the tail end missing!!! This fish came from the 'mini' layers. If this had a tail I would have paid some serious moneys for it!!! Just check out the anal fin!!!
  4. Fossil-Hound

    Muddy Wyoming Fish

    FYI @Ptychodus04 @Kittenmittens @mamlambo @Fossilis Willis @Malcolmt @DevonianDigger Well managed to get out last Friday to dig up some Green River fish from the split fish layers. These layers aren't nice and hard like the 18 inch, nor are the rarer fish as obtainable (they don't preserve as well), but you can still find some pretty cool stuff. A family next to me found a foot long Phareodus in perfect condition with a dark red color (forgot to take a picture of that). I don't think they realize just how lucky they are because those are not easy to find. The night before it rained a ton so I had a hard time getting to the quarry. The oily lime based rock wouldn't split properly until about noon but I hauled some decent Knightia's out. These aren't your prized, rare, fish but they are still a blast to dig up. Pulled out about fifty and worked all day. With all the mud and rain I seriously didn't think anyone would show up but Friday was very busy. About fifty in total came. The morning was tough. Lots of muddy rock to split and it just didn't want to split evenly. Everything would crumble on me. As you can see in the picture below things were muddy and wet. This Knightia has some pretty nice curves. Another curvaceous fossil. I'm in love. The split fish come in their varieties. Usually I only keep the ones that are completely filled in then put a sealant over them. This one looks alright considering it's a bit patchy. This one will be fun to prepare with my new CP9361 and some very careful handling of the scribe. This is one of my A grade Knightia's from the trip. Great color. The tail can be teased out a bit more. I really like how the vertebrae pop out in a 3D manner. Keep on fossiling!
  5. Jeff Browning

    ?? Bone or just interesting rock?

    Didn't pay much attention when I picked this up, just noticed it was interesting. It was a surface find and I guessed I would figure it out later. Any ideas? Found this somewhere south of Wamsutter, WY.
  6. oilshale

    Amphiplaga brachyptera COPE, 1877

    Amphiplaga is one of the rarer of the Green River fish fossils, making up some 1% of the total from Fossil Lake, its only known location. Amphiplaga belongs together with its close relative Erismatopterus to the family Percopsidae within the order Percopsiformes. Amphiplaga is best distinguished from Erismatopterus by its dorsal fin, which has three hard spines (the first one is very small) followed by 9 or 10 soft rays. Erismatopterus usually has two hard spines followed by 6 or 7 soft spines. Amphiplaga can reach up to 15cm with an average length of about 10cm while Erismatopterus does not exceed 12cm with an average length of about 5cm. The Order Percopsiformes is a small order of North American freshwater fishes that includes three families: Amblyopsidae (cavefishes); Aphredoderidae (pirate perches); and Percopsidae (trout-perches). Closely related to neither trout nor perch, trout-perches have characteristics of both the trout and perch families. They exhibit characters of the salmonids, such as an adipose fin, cycloid scales, and soft fin rays, as well as characters of the percids, such as dorsal and anal fin spines, and ctenoid scales. Trout-perch are generally silvery in appearance, often with a partially transparent appearance, and relatively large heads and eyes. They are small fish with weak fin spines, and an adipose fin similar to those of trouts. They feed on insects and small crustaceans. Fossil percopsids are only known from North America, the current home of the extant genus Percopsis References: E. D. Cope (1877) A contribution to the knowledge of the ichthyological fauna of the Green River shales. Bulletin of the United States Geological and Geographical Survey 3(4):807-819. Grande, L. (1984): PALEONTOLOGY OF THE GREEN RIVER FORMATION, WITH A REVIEW OF THE FISH FAUNA. THE GEOLOGICAL SURVEY OF WYOMING, BULLETIN 63,
  7. I am headed to Kemmerer with my son to look for fossils. I am aware of the quarries in Kemmerer and want to know if there is anything that we should not miss on our road trip or around the area. We have 5 days to explore. Thank you!
  8. Steveosaurus

    Fossils from the new guy

    I'm brand new to Fossil Forum, and can't afford the big splashy wall display fossils, so my "collection" is modest, but it's a start. I have three of these fern plates from St. Clair, PA, and two diplomystus fish fossils from the Green River formation in Wyoming.
  9. Hi all, I have been searching through posts in the forum about various types of abrasives, and I can't seem to find a comment anywhere where someone breaks down the pros/cons of the different forms of abrasive and their microns. Of course I realize everyone has their own preferences, I am just confused as to the objective benefits of what looks like the three main types of abrasives: dolomite, aluminum oxide, and just plain baking soda (besides the fact that baking soda is more delicate.) The Paasche Air Eraser comes with 240 micron aluminum oxide, but that seems to be a little extreme for fossil preparation, is there an appropriate time and place in which I could use that? What would be the max (or even a general range) micron of either dolomite or aluminum oxide that one would recommend I use for 1. Green River fish, 2. trilobites, 3. ammonites, or 4. just general fossil clean-up?
  10. Are these replica or genuine fossil? They look like the same.
  11. RCFossils

    Help With Green River Bird Leg

    I purchased a fossil collection several years ago that contained a beautifully preserved bird leg with some feathers preserved. It is was collected in the Green River Formation of Southwestern Wyoming. I know very little about fossil birds and am hoping someone on the Forum might be able to narrow the ID down to what family of bird it might be. Any Help will be greatly appreciated.
  12. I bought a small set of paints recently in a medium I had never used before, gouache. It's a lot like watercolor, but more opaque. I've always liked the look of watercolor but I've been more comfortable with acrylics. I thought I'd give the gouache paints a try, and I think I'm going to like them. Here's a Knightia I painted today, with an attached fossil Knightia. At least I think it's a Knightia. It's not preserved terribly well. I'm planning on painting some more knightia, probably a school of them, then a Diplomystus and maybe move on from there. It should be interesting.
  13. Fossil Claw

    crab ID

    Just curious. I keep seeing these hand mined boney crab fossils from the green river formation from Chinese sellers on an auction site. I have also seen them listed as from Madagascar. They don't look like green river fossils. Just wondering if they are real and where they actually come from.
  14. Fossil Claw

    First Green River fish prep

    I bought this 18 inch layer in March of 2016 from Blake. @FossilDudeCO Finally felt comfortable enough with the air scribe and micro air abrader to tackle it. looks like I might have found a bit of coprolite in there too. Needs a little bit more final clean up work but I am pretty happy with the way it turned out for my first one.
  15. Vaniman

    Fish IG.jpg

    From the album: Priscacara

    Vaniman <a href="http://www.yahoo.com">Vaniman</a>
  16. 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
  17. Hello everyone, A geologist friend of mine roped me into his love of all things ancient, so here I am new to the fossils, and new to the Fossil Forum. I received my first Green River fish slab yesterday and spent most of the day on and off working off the layers with dental scaler that I've used for in the past for Roman coins. Must say that this matrix is much easier than the stuff encrusted to the coins! So far I'm pretty happy with the progress, but am looking for advice on how far to take this so that I don't overwork the piece. Here are a couple of photos of the progress. Note the series of three stages use lighting from the top to highlight the 3D effect of the specimen. The other photo uses light from the lower left to show a more natural visual look if you just look at it laying on the table. I believe I still have a lot of detail work taking off sediment between the bones and along the spine, etc. Any advice on around the head and eye socket, the border? How about surface finishing? If the slab is dampened, the fish stands out more, so would a mat clear coat of something be a reasonable finish, or should I leave it alone? I believe I read that a 20% solution of white glue in water might create a good effect. Any experience with that? Again, there seem to be many schools of thought. Thanks in advance for your help. Also, I believe this is a Knightia, but wouldn't mind confirmation from someone in the know. The fish is almost exactly 4" head to tail. Again, thanks.
  18. oilshale

    Baenidae non det.

    Prof. WALTER G. JOYCE, Department of Geosciences, University of Fribourg has been kind enough to try to narrow down the species: "Of the four species that are known from the Lower Eocene of Wyoming, I can rule out one right away (Palatobaena gaffneyi), but the remaining three species (Chisternon undatum, Baena arenosa, and "Baena" affinis) are impossible to distinguish fresh from the egg because the shell has not yet formed. True, Chisternon undatum has been described from the Green River Formation, but I think there is no reason to exclude the other two species, especially since only one individual has ever been scientifically described from that formation. Thus, your turtle is probably only to be referred to as Baenidae indet."
  19. oilshale

    Baenidae indet.

    From the album: Vertebrates

    Baenidae indet. Eocene Ypresian Green River Formation Kemmerer Wyoming USA Length 90mm Might be Chisternon undatum Leidy, 1872, but turtles that size are almost impossible to determine.
  20. Tony G.

    Horsetail

    From the album: Green River Formation. Parachute Creek Member. Douglas Pass, Colorado

    Horsetail. Collected from the Green River Formation. Parachute Creek Member. Douglas Pass, Colorado. Radar Dome location.
  21. From the album: Green River Formation. Parachute Creek Member. Douglas Pass, Colorado

    Unidentified insect from the Green River Formation. Parachute Creek Member. Douglas Pass, Colorado. Radar Dome location. 5/8" across.
  22. Tony G.

    Platanus wyomingensis

    Collected South of the Radar Dome near the cliff face.
  23. Tony G.

    Cardiospermum coloradensis

    Collected South of the Radar Dome near the cliff face.
  24. oilshale

    Amia pattersoni GRANDE & BEMIS, 1998

    Taxonomy from Grande & Bemis 1998. Species diagnosis from Grande & Bemis 1998, p. 189:" Amia pattersoni sp. nov. differs from all other known amiine species in the following adult characters A through H. (A) The number of subinfraorbitals (four or more) is higher than in any other amiid. (B) The gular is longer and narrower than known in any other species of Amiinae. The center of ossification of the gular lies within the posterior half of the bone (indicated by ornamentation pattern) unlike †A. "robusta" where it lies in the middle of the bone. (C) The frontals are narrower than in any other species of Amiinae (width-to-length ratio = 0.31-0.36, Table 41, compared to 0.47-0.65 in A. calva, Table 2; 0.43-0.49 in †A. scutata, Table 21; 0.36-0.37 in † "A." hesperia, Table 31; and 0.40-0.55 in †Cyclurus, Tables 50, 60, 70, and text). (D) Mandible is longer than known for any other species of Amiinae (mandible as 7322 percent of head length is 69%-71%, Table 40, compared to 56%-68% for A. calva, Table 1; 59%-66% for †A. scutata, Table 20; 62% for t "A." hesperia, Table 30; and 51%-65% for †Cyclurus, Tables 50, 60, 70, and text). (E) Number of dorsal fin rays and radials differs from that of any other known Amia (45-47 segmented rays and 44-48 proximal radials, Table 48, compared to 48-51 segmented rays and 49-52 proximal radials for A. calva, Table 16; 51-53 segmented rays and 51-54 proximal radials for †A. scutata, Table 28; and est. 40 segmented rays and 39 proximal radials in † "A." hesperia, Table 38). (F) Fewer abdominal centra are present than in any other species of Amia (30-33, Table 45, compared to 38-40 in A. calva, Table 11; 33-34 in †A. scutata, Table 25; 32 in † "A." hesperia, Table 35). (G) The absence of the lacrimal notch. This notch (for articulation with the first subinfraorbital) is usually present in all other species of Amia. (H) The posterior margin of the opercle is sigmoidal, bulging convexly along the lower half and slightly concave along the upper half, unlike all amiines except for †A. "robusta". Characters B, C, and D above are correlated with an elongated skull in this species." Line drawing from Grande and Bemis 2002, p. 186; References: L. Grande: An updated review of the fish faunas from the Green River Formation, the world's most productive freshwater Lagerstaetten. In Eocene biodiversity., unusual occurrences and rarely sampled habitats. Gunell, Gregg F., eds, Topics in Geobiology, Vol 18, p. 1-38. Lance Grande & William E. Bemis (1998) A Comprehensive Phylogenetic Study of Amiid Fishes (Amiidae) Based on Comparative Skeletal Anatomy. an Empirical Search for Interconnected Patterns of Natural History, Journal of Vertebrate Paleontology, 18:S1,1-696, DOI: 10.1080/02724634.1998.10011114
  25. oilshale

    Astephus antiquus (Leidy, 1873)

    Astephus and Hypsidoris are both members of the Family Ictaluridae, native to North America. Green River catfish are easily recognized by their stout dorsal and pectoral spines, scale less bodies and broad skull. Ictalurid species have four pairs of barbels (or whiskers). Like modern catfish, they possessed a vibration sensitive organ called the Weberian apparatus. The Weberian apparatus consists out of specialized vertebrae at the front of the spinal column which passed vibrations to the inner ear using the swim bladder as a resonance chamber. The structure essentially acts as an amplifier of sound waves that would otherwise be only slightly perceivable by the inner ear structure alone. Normal size of Astephus is around 15cm and rarely exceeds 18cm, maximum total length is about 30cm. Hypsidoris seems to be in the same size range. The easiest way to distinguish Hypsidoris from Astephus is by counting anal fin rays; H. farsonensis has about 15 to 17 and A. antiquus has about 26. The diet of Green River catfish was probably similar to existing ictalurids consisting of plants, small fish, crayfish and mollusks. Astephus and Hypsidoris were probably bottom feeders. Astephus antiquus is unknown as a body fossil in the middle unit of Fossil Butte Member, and only one specimen has been found in all of Fossil Lake, although it is abundant in Lake Gosiute strata. The discovery of numerous and widespread fossil catfish in oil shale units of the Laney Member of the Eocene Green River Formation is evidence of aerobic conditions in the hypolimnic waters of ancient Lake Gosiute. Hypsidoris farsonensis has only been found in Lake Gosiute deposits of the Green River Formation, east of Fossil Lake. Revised Species Diagnosis from Grande & Lundberg 1988, p. 146: "An extinct genus of ictalurid catfish that differs from all other known ictalurids by the following combination of characters: lack of jawmuscle origin on the temporal region of the skull roof, the possession of villiform vomerine teeth, the possession of tooth plates lateral to the vomerine tooth plate, and the location of the cranial opening for the infraorbital canal in the sphenotic rather than the frontal. Admittedly none of these characters alone is unique to †Astephus, but the combination of all of them is. The genus appears to be unique among catfishes in having the ventral surface of the supraethmoid inclined sharply upward relative to the ventral surface of the vomer. No other characters apparently unique to the genus were discovered here." Emended Species Diagnosis from Grande & Lundberg 1988, p. 147: "A species that differs from the only other known species recognized here (tA. antiquus) by the presence of a narrower vomerine tooth patch. Also, the median supraethmoid cleft appears to be deeper and the cranial fontanelles appear to be wider than in †A. antiquus (although the latter feature is possibly an artifact of preservation)." Line drawing from Grande & Lundberg 1988, p. 151: Identified by oilshale. References: Grande, L. and J. G. Lundberg. 1988. Revision and redescription of the genus Astephus (Siluriformes: Ictaluridae) with a discussion of its phylogenetic relationships. J. Vert. Paleont 8:139–171 Grande, L. 1987. Redescription of Hypsidoris farsonensis (Teleostei: Siluriformes), with a reassessment of its phylogenetic relationships. Journal of Vertebrate Paleontology 7:24–54. Grande, L. and M. C. C. de Pinna. 1998. Description of a second species of the catfish Hypsidoris and a reevaluation of the genus and the family Hypsidoridae. Journal of Vertebrate Paleontology 18:451–474.
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