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Hi everyone! I think I'll skip the fluff and just get to my points on why I think that's what this one is. ID as Ceratopsian horn: The piece is from Powder River County, Montana. It measures 22.2 x 10 x 8.3 cm. The last two pics show the circular cross section and then blood grooves. The Bite Marks and comparison to a published specimen: Aside from a huge crescent shaped gouge on the distal end I have counted several individual scour marks. A similar specimen has been documented with the same huge crescent shaped gouge with individual scours in almost the exact same places. Here is a quick overview of the individual marks on this specimen and a comparison to the published specimen. I will go into each mark in detail. First is the published specimen as well as the website I saw it mentioned and the original article. My specimen: Main Scour Mark A: A Large Tooth from Tyrannosaurus rex (CH 7.5 cm) fits almost perfectly into MSMA. The mesial carina aligns perfectly with the serration mark. Smaller teeth would not fit. The tooth was found in Garfield County, Montana. Main Scour Mark B: MSMB with the tip of another large T-Rex tooth fit in. The mark measures 10.28 mm long and 7 mm wide. Like MSMA, it was created by the mesial edge of the tooth. The teeth used to fill each mark were photo'd in their approximate position showing them as roughly parallel. The marks are 6.9 cm apart. Both are in almost the exact same position and distance apart as the published specimen mentioned earlier. Secondary Scour Mark A: Very close to, but at an angle to MSMA. There is and area near the scour which might be a continuation though I am not sure. Without the questionable area it measures 13 mm long and 6.2 mm across. Secondary Scour Mark B: This scour mark isn't as deep as the others but is longer at 24.8 mm. Another Scour mark was documented in this are on the published specimen but was at a different angle. Identification of the Bite Marks as Tyrannosaurus rex: In the Hell Creek Formation of Powder River County three large species of Theropod dinosaur are known, Dakotaraptor steini, Nanotyrannus lancensis, and Tyrannosaurus rex. Given the size of tooth required to make MSMA, the best preserved of the scour marks in my opinion, I believe both Dakotaraptor and Nanotyrannus can be ruled out. The fit of a large Tyrannosaurus rex tooth in both size and shape into MSMA also provides evidence even beyond process of elimination of other species. What's more, the existence of a remarkably similar fossil of a Ceratopsian horn with both very similar damage morphology of the distal end and scour placement would indicate consistency in the interaction between Tyrannosaurus and large Ceratopsians. Okay, I had my fun playing paleontologist. So what do you all think? Any insight is greatly appreciated as always!

Hi everyone, I have my eye on a large tooth that the seller claims is a Rex from the Hell Creek of Montana, but doesn't have any more proximity information. Now normally in this sort of case that would be the end of the story as Late Cretaceous Montana Dinos can get kinda goofy especially when Tyrannosaurs are concerned with all the different Tyrannosaur bearing beds being so close to each other, but I'm wondering if this tooth might be an exception to the "call it indet. Tyrannosaur without an exact location in Montana rule" as the tooth is a BEAST. It appears to be a Premax crown well over 2.5 inches and I'm wondering if that eliminates the other Tyrannosaurs from size alone. Any feedback is appreciated as always!

Hi everyone, I recently acquired a batch of small theropod teeth and was hoping to get a second opinion on some ids since a few seem kinda special. The first one I'm really leaning towards Dakotaraptor. 2-5 I'm not sure. They're all very similar looking but have very different base shapes including oval, almond, pinched rectangle, and pinched almond. The serration densities are also very interesting. The mesial serrations on all are much smaller than the distal serrations. The last one I think is a really tiny T-Rex. It's a dead ringer for a large Rex just very small. All six are from The Hell Creek of Carter County, Montana. Any insight is greatly appreciated as always! Tooth 1: Tooth 2: Tooth 3: Tooth 4: Tooth 5: Tooth 6:

Hi everyone! I acquired a bunch of Tyrannosaur tips from Hell Creek recently. Most were sold as Tyrannosaur indet. which is what I've been going by for them except the ones with a really thick, almost circular cross section. These three I'm kinda on the fence as they're pretty robust but not circular. All three are Hell Creek but from different localities which I have next to each one. Also when I took the cross section measurements I didn't take those at the end of the base because it was uneven on all of them, being broken tips. So what I did was I went up a little to a complete cross section that was perpendicular to the height measurement and took my cross section measurement there. So what do you all think, can these be labeled Rex? Should I continue to call them indet.? Any feedback is greatly appreciated as always!

Hi everyone! I recently acquired this from the Hell Creek of Carter County. I assumed it was a juvie Rex and but was asked to check the serration density and it came back weird so I thought I'd ask for some input. I'm hoping I can at least rule out Nano which I will be shocked if this even has the possibility of being Nano. We might be looking at another "Larsonraptor" situation (if you know you know). CH is 26 mm CBL is 11 mm CBW is 8.18 mm mesial serration density is 14 for 4 mm distal serration density is 10.5 for 4 mm DSDI is 4/3 Any insight is appreciated as always!

Hi everyone! I have my eye on a potential Rex but the seller isn't sure if it's a rex or a huge Nano. The measurements they gave are 1.75 x .6 x .37 Inches so about 4.46 x 1.52 x .94 cm. It's from powder River County Montana The tooth is an anterior and the oval shaped base combined with it being that large of an anterior says rex to me, but I figured I'd seek a second opinion.

Hi everyone! I acquired these two pretty recently and immediately though Juvenile Rex, but after that other one I figured I should be more careful and ask for a second opinion. Both are from the Hell Creek of Powder River County, Montana. Tooth 1: Crown Height: 11 mm Crown Base Length: 5.5 mm Crown Base Width: 5 mm Mesial serration density: 4.5 per mm Distal serration density: 4 per mm Tooth 2: Crown Height: 14 mm Crown Base length: 7 mm Crown Base Width: 5 mm Mesial serration density: 4.5 per mm Distal serration density: 3.25 per mm