Troodon Posted January 11, 2018 Author Share Posted January 11, 2018 12 minutes ago, -Andy- said: I see you have found a new way of photographing your raptor teeth. The 8mm tooth is incredible. For the 12mm tooth, wouldn't it be S. langstoni due to upwards pointing serrations? Ha ha have less lazy so taking the time to do it this way. Yes, splitting hairs on the 12 mm tooth but it really has not been reported from the JR (Currie 2013) so who knows Link to comment Share on other sites More sharing options...
hxmendoza Posted January 13, 2018 Share Posted January 13, 2018 On 1/10/2018 at 1:34 PM, Troodon said: Old teeth new pictures Beautiful teeth @Troodon. I do question the 25mm Dromaeosaurus tooth ID. I think it may better fit the first caniniform maxillary tooth of Nanotyrannus. Maybe even the second maxillary tooth. Any pics of the base? Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 1 minute ago, hxmendoza said: Beautiful teeth @Troodon. I do question the 25mm Dromaeosaurus tooth ID. I think it better fits the first caniniform maxillary tooth of Nanotyrannus. Maybe even the second maxillary tooth. Any pics of the base? Thanks, that tooth is Judith River Link to comment Share on other sites More sharing options...
hxmendoza Posted January 13, 2018 Share Posted January 13, 2018 9 minutes ago, Troodon said: Thanks, that tooth is Judith River Oops!! I didn’t bother reading the formation. Sorry! LOL! Okay then, possibly the first maxillary tooth of a Gorgosaurus-like tyrannosaur (If not Gorgosaurus sp. itself). What do you think? Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 I thought the serration density was different need to recheck and get back. If they are the same definitely Tyranno. Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 @hxmendoza serration density that of a Dromie 1 Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 A few JRF Tyrannosaurid Teeth from my collection Positional Teeth 4 Link to comment Share on other sites More sharing options...
hxmendoza Posted January 13, 2018 Share Posted January 13, 2018 2 hours ago, Troodon said: @hxmendoza serration density that of a Dromie Okay, good to know. Big tooth! Link to comment Share on other sites More sharing options...
-Andy- Posted January 13, 2018 Share Posted January 13, 2018 Beautiful teeth as always! By the way, Frank, have you ever done a distal mid-crown serration count for your tyrannosaurids? Reading off "Dental Morphology and Variation in Theropod Dinosaurs: Implications for the Taxonomic Identification of Isolated Teeth", I noticed that the distal mid-crown denticle density of Daspletosaurus was in the range of 9.0 - 11.2, while Gorgosaurus was 10.0 - 15.0. We talked briefly about this, but didn't look into it any further. I am curious to see if your bigger "likely-to-be-Daspletosaurus" teeth fulfills this rule too. My 3-incher JRF tyrannosaurd crown (which I like to imagine is Daspletosaurus) has 10/5mm on the midline. Meanwhile, my two smaller JRF tyrannosaurids (1.2 inch crown, and 2 inch crown) have 13 to 14/5mm on the midline. Due to low sampling data on my part, I can't tell if the size of the teeth causes this difference in serration count. 2 Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday! Link to comment Share on other sites More sharing options...
hxmendoza Posted January 13, 2018 Share Posted January 13, 2018 3 hours ago, Troodon said: A few JRF Tyrannosaurid Teeth from my collection Positional Teeth Beautiful. That little rooted posterior tooth is fantastic! Link to comment Share on other sites More sharing options...
Bobby Rico Posted January 13, 2018 Share Posted January 13, 2018 @Troodon your collections are fantastic and this is no exception just stunning and very informative. cheers Bobby Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 1 hour ago, -Andy- said: Beautiful teeth as always! By the way, Frank, have you ever done a distal mid-crown serration count for your tyrannosaurids? Reading off "Dental Morphology and Variation in Theropod Dinosaurs: Implications for the Taxonomic Identification of Isolated Teeth", I noticed that the distal mid-crown denticle density of Daspletosaurus was in the range of 9.0 - 11.2, while Gorgosaurus was 10.0 - 15.0. We talked briefly about this, but didn't look into it any further. Cheers I am curious to see if your bigger "likely-to-be-Daspletosaurus" teeth fulfills this rule too. My 3-incher JRF tyrannosaurd crown (which I like to imagine is Daspletosaurus) has 10/5mm on the midline. Meanwhile, my two smaller JRF tyrannosaurids (1.2 inch crown, and 2 inch crown) have 13 to 14/5mm on the midline. Due to low sampling data on my part, I can't tell if the size of the teeth causes this difference in serration count. I did a study on all my Tyranno teeth from the Hell Creek and the size of the tooth has a direct bearing on the density of the serrations. This is why one cannot generalize about density you need to know the size of the tooth. Nano Teeth 7/16 to 1" : Serrations Density 4.5 to 3.4/mm 1" to 2" : Serrations Density 3.1 to 2.7/mm Rex Teeth Size: 1/4 to 1" : Serration Density 4.3 to 3/mm 1" to 2" : Serration Density3.4 to 2.5/mm 2.5 to 3.5" : Serration Density 2 to 1.8/mm 4.5" : Serration Density 1.6/mm 5.3" : Serration Density 1.4/mm In that paper I believe all the teeth fit into a size range. Anyway my 87mm tooth is 10/5mm and my 52mm one is 12/5mm 2 Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 27 minutes ago, hxmendoza said: Beautiful. That little rooted posterior tooth is fantastic! Thanks Henry. I spoke with Calvin about the size of Dromaeosurus teeth he's seen and they can get quite large he said. 9 minutes ago, Bobby Rico said: @Troodon your collections are fantastic and this is no exception just stunning and very informative. cheers Bobby Thanks Bobby 1 Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 @-Andy- updated my rex density from above added a 5.3 tooth Did some more JRF teeth. Could not do 5mm on all the teeth so adjusted all to 1mm. 12mm - 4.5/mm 14mm - 3.3/mm 15mm - 5 to 6/mm 19mm - 3.3/mm 26mm - 3/mm 34mm - 2.6/mm 60mm - 1.8/mm So my 3 3/8 " (87mm) tooth still fits the parameters of being a possible Gorgosaurus but my 60mm one is probably a Daspletosaurus at 9/5mm. So +3" does not guarantee you a Daspletosaurus, that theory is BUSTED . You need to buy a tooth not based on size but serration count but that is still no a guarantee.. it needs to come from a Daspletosaurus graveyard. When we have this discussion I'm always reminded of this picture I took at the Tyrrell. Goro teeth can get pretty big. 5 Link to comment Share on other sites More sharing options...
Troodon Posted January 13, 2018 Author Share Posted January 13, 2018 @-Andy- Took a look at my Two Medicine teeth comparable view. My big one looks like Daspletosaurus it's 4" and 9/5mm Around 2 1/2" they ranged 13 to 15.5/5mm Around 1 1/2" they ranged 11 to 13/5mm Don't have any in the 3" range Link to comment Share on other sites More sharing options...
bcfossilcollector Posted January 14, 2018 Share Posted January 14, 2018 Beautiful teeth. Truly stunning. Link to comment Share on other sites More sharing options...
-Andy- Posted January 14, 2018 Share Posted January 14, 2018 @Troodon Thanks for the info. Any clues to the crown size of that enormous Gorgosaurus? I updated the tyrannosaurid teeth chart for easier reading. The number next to the dinosaur name represents measurements in inches rounded down to 2 decimals. Still trying to understand this data. Only thing I can see is that n average, Daspletosaurus teeth are bigger than Gorgosaurus teeth. The average crown height of Gorgosaurus teeth is 1.592 inches. The average crown height of Daspletosaurus teeth is 2.297 inches. But we already knew Daspletosaurus tend to be bigger. Of note is that ROM1247 used for the Gorgosaurus and MOR590 for Daspletosaurus are subadults. AMNH 5346 is considered an adult (though not the biggest specimen of Daspletosaurus known). BMNH R4863 Gorgosaurus specimen seems to be an adult; some older papers even classify it as a Daspletosaurus but I will need to get more info. 2 Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday! Link to comment Share on other sites More sharing options...
Troodon Posted January 14, 2018 Author Share Posted January 14, 2018 @-Andy- nice work on that chart easier to read.. Did not have a scale on those teeth from the Tyrrell but they were at least 3". BTW, MOR590 is the Two Medicine Formation type specimen Daspletosaurus horneri not D. torous. My guess is the teeth they used were tied to known skulls so it's somewhat biased based on what they used for the paper. I think all you can gather from the study is that the density of Gorgo teeth trend higher than Daspleto and can possibly be used to identify Gorgo teeth if greater than 12/5mm and Daspleto if 9/mm but it's an unknown if it fall between those two. Pretty close tolerances to make that call and if adult skulls were used would the data be different....guess why we ID them as Tyrannosaurid indet. 3 Link to comment Share on other sites More sharing options...
Troodon Posted January 14, 2018 Author Share Posted January 14, 2018 @-Andy- check out the chompers on this Gorgo being worked on at the BHI, cast going to the children's museum of Indianapolis 4 Link to comment Share on other sites More sharing options...
Bobby Rico Posted January 14, 2018 Share Posted January 14, 2018 @Troodon that is some serious casting work. Kids of Indianapolis are in for a treat. Link to comment Share on other sites More sharing options...
-Andy- Posted January 14, 2018 Share Posted January 14, 2018 Good gracious. I could have mistaken that for a T-Rex. Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday! Link to comment Share on other sites More sharing options...
Troodon Posted January 14, 2018 Author Share Posted January 14, 2018 14 minutes ago, Bobby Rico said: @Troodon that is some serious casting work. Kids of Indianapolis are in for a treat. Its a beautiful skull believe its from the Two Medicine Fm of Montana. The original was at the Tucson show a few years ago. Yep the museum will enjoy it. 1 Link to comment Share on other sites More sharing options...
oldtimer Posted January 15, 2018 Share Posted January 15, 2018 What an awesome cast. Glad to see it will be on display at a children's museum. That is sure to spark a big interest from kids as well as their parents. Link to comment Share on other sites More sharing options...
fossilsonwheels Posted February 24, 2019 Share Posted February 24, 2019 Thank you @Troodon for all of the informative and helpful posts. Your Judith River collection was of particular interest to me as this is a formation we are focusing on. The information was awesome and your collection is amazing. Those beautiful Dromaeosaurus teeth might be my favorite. Link to comment Share on other sites More sharing options...
hxmendoza Posted April 26, 2019 Share Posted April 26, 2019 Great info on the Judith River Tyrannosaur denticle counts Frank. Thank you! 1 Link to comment Share on other sites More sharing options...
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