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  2. Cretaceous pliosaur and polycotylidae teeth have obvious striations/ridges. Meanwhile, elasmosaur teeth are curved and have a round cross section. Most of the teeth at the top seems to be Protosphyraena. Source: http://oceansofkansas.com/Protosphyr.html The 2nd tooth from the top right seems to be Xiphactinus. Source: https://www.georgiasfossils.com/7d-xiphactinus-vetus.html The teeth at the bottom doesn't look anything like Coniasaurus which are much smaller than this. cf. Coniasaurus sp. teeth If I had to hazard a guess, I'd say bottom row looks like a mix of Hesperornithiforms teeth, along with some other marine reptile (maybe plesiosaur?). Hesperornis regalis fossils
  3. Much better photos... bought a better USB microscope. Cheers, Rich
  4. A new pterosaur-related paper is available online: Rodrigo V. Pêgas, Borja Holgado & Maria Eduarda C. Leal (2019). On Targaryendraco wiedenrothi gen. nov. (Pterodactyloidea, Pteranodontoidea, Lanceodontia) and recognition of a new cosmopolitan lineage of Cretaceous toothed pterodactyloids, Historical Biology, DOI: 10.1080/08912963.2019.1690482 Targaryendraco constitutes a distinct form of Anhanguera-like pterosaur, being united with Aetodactylus, Aussiedraco, Barbosania, Camposipterus, and Cimoliopterus in the new clade Targaryendraconia. It's quite ironic that Targaryendraco was originally assigned to Ornithocheirus based on comparisons with Lonchodectes compressirostris (formerly erroneously regarded by some as the type species of Ornithocheirus), because its holotype doesn't overlap with that of Ornithocheirus simus. The genus name is also tongue-twisting because it honors a fictional character from Game of Thrones. By the way, is there a copy of the Targaryendraco paper I could look at?
  5. Today
  6. Very nice clams! I really love the one with the iridescence. Thank you also for the historical and scientific descriptions you have provided with each of these posts.
  7. Hell creek T-rex tooth

    Beautiful specimen!
  8. Hello, I recently made a post about some finds collected from a marine Cenomanian bonebed, but I was so distracted with identifying the hesperornithine bones from the mix of vertebrate remains that I haven't had a chance to positively ID some of the marine reptile teeth found in the assemblage... The teeth in the top row all appear to be from the same species, and are highly compressed, lingually. They appear striated, but are actually completely smooth, and have no occurences of serrations on the edges. I had another really nice one about the same length as that long one but a friend is holding on to it now, so regretably no pics. The second row are also all superficially similar. Notice the prominent, striated ridges which occur only on the middle portion of the tooth, from the end of the root to about 3/4 to the tip. This occurs on all but the middle tooth, which is completely smooth, leading me to believe that it might have belonged to a different species entirely. All of the teeth are more or less round at the bottom. Marine reptiles reported from this formation include indeterminate elasmosaurs and pliosaurs, as well as a dolichosaur suspected to be a certain Coniasaurus crassidens. I suppose my two main questions are as follows, -Do the teeth at the top belong to an elasmosaur or pliosaur? They quite appear different from examples I've looked at online from either group, so I'm a little stumped. -Do the teeth from the bottom row belong to Coniasaurus, and if so, does the tooth without ridges come from a different group than the one with ridges? (it's the only one I found that looks like that, by the way, from among the hundreds of teeth recovered from the bonebed)... As always, any extra input is always welcome. Thanks for your attention.
  9. Hell Creek Fish (?) Jaw Section

    Very cool. Compare with the Amiid (fish), Melvious.
  10. The Rio Puerco Valley

    ... .... Hope you all have waay too much fun while finding lots of fantastic fossils... ...happy hunting! -P.
  11. The Rio Puerco Valley

    In the last few months, I've had three opportunities to wander the Puerco...some lovely days scouring Upper Cretaceous shale... ...
  12. Here are a few examples preserving “death trails”. The second specimen is pictured in The Mazon Creek Fauna book.
  13. Myrtle Beach Mammoth?

    Nice Find!
  14. Hell creek T-rex tooth

    That's absolutely stunning. Congratulations... enjoy it. I think you got a real winner there.
  15. This is an interesting specimen that has some unusual mineralization. Almost looks like ammolite.
  16. This is a beautiful example preserving multiple individuals.
  17. This next species is the second most common animal found in the Essex portion of the Mazon Creek deposit. While there are over a dozen described bivalves found in the Mazon Creek deposit, Mazonomya is by far the most abundant. It is restricted to the Essex (marine) portion of the deposit, where in some areas have been found to make as much as 70 percent of all bivalves collected. At one collecting site, these clams are so common the area has been nicknamed Chowder Flats. Despite the abundance of specimens, Mazonomya was not formally described until 2011. For years it had been misidentified as a type of bivalve named Edmondia. Current research has shown it is actually a Solemyid. Before formal description, Mazon collectors referred to these bivalves as clam-clams due to the fact that they are often preserved in a death position with both valves opened. Mazonomya is the largest clam found in the deposit . While quite rare, specimens have been found over 4 centimeters in length. preservation can be excellent and in some cases, soft tissue can be preserved. Specimens have been found with preserved “death trails”. Solemyids are still found today in oxygen poor and sulfide rich marshes. This first specimen is the largest in my collection. The valves measure almost 4 centimeters. There is also some evidence of the hinge ligament (soft tissue) between the valves.
  18. Hell Creek Fish (?) Jaw Section

    Hey everyone, I found this little jaw section at a microsite in North Dakota's Hell Creek formation this past summer and I'm finally getting around to posting about it. I believe it's fish, possibly gar, but I'm not sure. I'd like to know people's opinions. It's about 1.3 centimeters long. Thanks, Noel
  19. White River Oligocene Prep - Leptictis

    This is nice, Tim, but I respectfully disagree with a lot of it. This description fits Leptictidium, from Messel, which had inordinatley long back legs. Lepticitis's legs are not nearly as strangely proportioned. Its front half is strongly developed for digging. Also there is no proof of a long snout on Lepticitis, like there is on Lepticitidium. I have a complete skeleton here and it is very different from Lepticitidium.
  20. Myrtle Beach Mammoth?

    oh yeah!!
  21. Dr Mud & The Crab Concretion Crusade

    A pneumatic cutoff saw and diamond blade like @crabfossilsteve recommended is a much cheaper option that the super Jack. You just have to be careful as once you cut through the crab it’s hard to fix! With crabs you just have to be careful of the position of the limbs and give a generous margin of error. Its always a nervous time cutting the rock and chiselling it off! I cut through a shark vert as I was trimming a block full of shark verts, but hey, this stuff happens unless you have x-ray vision or access to medical imaging! @6ix has been kind enough to let me use his set up.
  22. Dr Mud & The Crab Concretion Crusade

    Great idea @crabfossilsteve A good way to deal with the wobble. I guess if the work is super fine you can always switch to a microjack. That’s how I work with fossil crabs.
  23. Dr Mud & The Crab Concretion Crusade

    So much good crab prepping info in this thread! Thanks @RJB for showing the prepping tools - I think the ME9100 will be my next tool I get. It sounds like exactly what I need!
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