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Working on a Hyracodon Skull, still have some work to do, but here is the progress so far. What do you guys think?

Got this jaw/skull piece at a shop recently that was labeled Hyracodon. I don't think it looks like Hyracodon, but I don't know what it could be. Any ideas?

Good evening I have a Hyracodon skull. Nearly complete, but does have some putty work done to the upper. Excellent teeth. I have two of these and wouldnt mind losing one. I just wanted to see what any of you had to trade of equal value. Not really looking for anything in particualar. Show me what you are willing to trade!

I just got back from an amazing and very fruitful week of fossil collecting on the White River Formation in northeastern Colorado. The White River Formation is a very easy and fun rock unit to collect vertebrate fossils on. The White River Formation was deposited during the very latest Eocene and the early Oligocene, though the faunal diversity in the areas I was collecting on suggest it was laid down during the Orellan North American Land Mammal Age, which centers on around 33 million years ago during the Rupelian age of the Oligocene Epoch. I am very lucky to have a grand uncle Gary (no biological relationship to me, is a close family friend who we’ve called “uncle” since I was a toddler) who is a cattle rancher up in northeastern Colorado, and he happens to have a pretty good amount of White River exposure on his property, in addition to some of the neighboring ranches of which Gary knows the owners and helped me to secure permission to collect on a few of them. He really is a great guy and is a real life true American cowboy. He has an interest in natural history and was eager to hear all about the fossils and geology of the area, though has never had the formal education or done the research to learn much about what’s out there. This is the second fossil collecting trip I’ve made to the ranch, though the first one where I’ve stayed for more than one night. The place truly is an amazing trove of fossil treasures and I can’t wait to tell you all about my week! In this thread I’ll make one post for each day (so as to not hit the picture limit too soon). Once I have the fossils prepped I’ll give updates here as well. Day 1, Sunday: My first day at the ranch began, ironically, at my own house. I had packed up the Jeep the night before with my field bag, two coolers filled with seven day’s worth of food, a suitcase full of clothes, and other such supplies for my fossil safari. I left my home early in the morning, took I-76 east to Fort Morgan, and then headed north to the ranch, in total about a 2.5 hour drive. The rest of the morning and early afternoon I spent visiting with and going over logistics with Gary and his wife and settling in at the ranch house I would be staying at, a property that used to be the home of another rancher before Gary acquired the property in 2002. They still maintain the house and it has both electricity and running water, so it makes a fantastic guest house and a place to stay when they’re doing work over on that side of their land. In the evening after I had made myself a quick dinner I decided I wanted to head down to a very productive exposure I had collected on last September for the evening. There was a partial oreodont skeleton that I had discovered eroding out of the hill the last time I was up there, and I wanted to see if there were any more bones there that had eroded out and I could collect. I picked up a few more bones from the feet and ankles that had been exposed in the last eight months and decided to take a scenic route back to my vehicle. A photo of the area of exposure I was in Sunday evening. This piece of badland will become very important throughout the rest of the week... On my walk back I walked over a ridge that I had apparently never been over, becase on a flat wash I noticed a pile of bone fragments. I approached the pile assuming that it would be yet another exploded tortoise shell that are so common in the area. As I got closer however, I was delightfully surprised to see the distinctive black color of fossil enamel, and a bit of digging revealed an eroded Subhyracodon jaw section, along with several loose teeth that I presume had come from the same section of jaw. This find, along with an oreodont jaw section I found later on while walking back to the Jeep that night, would be but a foreshadow of the big finds I would make later in the week. Two photos of the Subhyracodon jaw section as it was found in the field. The jaw section and some teeth after I had cleaned them up a little bit at home this afternoon.

I got this broken up jaw recently and finished putting it together (and some cleaning) today. I still have a little matrix to remove, but it's already good looking Its from the White River Formation in Wyoming. I'm not 100% certain on ID but I'd pretty sure it can be called Subhyracodon sp.

Hello I'm a newbie fossil collector (and newly active member) who happens to several interesting fossils for a decent price from our favorite auctions sites 1st is are Knightia. The seller claims that they are not restored or enhanced 2nd set are 4 Spinosaurus teeth. The seller claims that cracks have been repaired, but no restoration or composition has been made (Pictures 2-9 of teeth in pairs) 3rd is a Lycoptera which the seller claims is not restored or enhanced 4th are plates of Elrathia Trilobites from Wheeler Formation 5th are Fossil Ferns from Llewellyn Formation 6th is a Hyracodon jaw fragment I would like to ask if the sellers' description of the items are accurate and/or if they are restored, enhanced or composites. Cheers!

Hello TFF. This was brought to me today with no location info. It looks like Oligocene White River Group. Person who brought it in said it was collected by his grandparents who took trips to S. Dakota, etc. It is pretty "beat up". My first thought was Hyracodon from the White River Group. It's not Oreodont. Teeth are heavily eroded. The matrix is more reddish than anything I have collected in Nebraska, so maybe it's from S. Dakota? Thoughts? @Nimravis, @jpc (darn blurry pics. I even used a copy stand and timer...) Labial Lingual Occlusal (lingual side toward bottom)

My post comparing astragalus (ankle bone) generated some doubt/question as to the proper identification of a hyracodon astraglus I bought recently. So, I bought a subhyracodon astragalus from the same person found in the same area for comparison. Doubt arose from some forum users if the fossil I bought as a hyracodon astragalus since it agreeably doesn't have the characteristics of a rhino type animal. The hyracodon is thought to be the earliest ancestor of the rhino or general classification of such animals. The fossils I picture are from Pennington County, South Dakota, White River formation, Oligocene era. I searched the internet high and low, inside and out, relentlessly seeking a good clear picture of an hyracodon astragalus and failed miserably. I read many articles describing the hyracodon and in the end seemed to know less than when I started. The internet is a vast ocean of information but I find more and more conflicting, incomplete or simply misleading information. Getting clear definitive data can be difficult or impossible. My suspicion is maybe it could be somewhat misleading to classify the hyracodon in the rhino family of animals since most everything I read said it was more horse like in appearance. The subhyracodon astragalus is amazingly similar to that of a modern horse. Yet, the subhyracodon as described was a true rhino in appearance so it should be no surprise it's astragalus looks like one of a rhino. The other part of this story is I bought the two astragalus from a well established, well respected dealer who sells a lot of Oligocene era fossils. He also operates a web site dedicated to the White River formation. If anyone should know I figure it's him and have always trusted his judgement concerning the identification of the fossils I bought from him. Sure, no one's perfect but that would be a major boo boo for someone with his experience and reputation.