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Found 21 results

  1. Tyrannosaurid Indet Confirmation

    Hello all, Recently acquired 2 teeth, found and sold together, that I would love some insight and second opinions on. Both teeth are described as Tyrannosaurid Indet, from the Judith River Formation. The seller described that he purchased them both together from the harvester, but due to the fact he was not the original collector, the information is isolated to the above information. Smaller tooth is 15/16" long, dark chocolate color, and 1/4" wide. Serrations are present on front and rear edges, with serrations starting midway on the front edge. Larger tooth is missing the front edge, appears sheared. Length is 1 1/8", width 5/16". Serrations present cleanly on rear edge, but again completely sheared from front edge. Color also deeper chocolate brown, but more horizontal banding. Can obtain more detailed and specific measurements of other needed dimensions if needed. Mainly I'm looking for a confirmation of Tyrannosaurid Indet distinguished from other theropods in the area at the time, as I have little experience positively IDing smaller tyrannosaurid material. I've actively worked on distinguishing Carcharodontosaur teeth from Rugops in the field in Morocco, but this is out of my field. All help is greatly appreciated! Will post more pictures in comments
  2. Today is my last day off before I go back to work and I was supposed to spend the day making fossil starter kits. I have a cold though and I do not want the kids to think that 12 million year old shark teeth gave them a cold lol I am pretty bored so I thought I would post about our Judith River dinosaur fossils and how we are going to get discuss this formation. I am really surprised how much I am enjoying learning about these dinosaurs and this will be a formation that we spend a good bit of time on. It must have had some very productive ecosystems and there is a great diversity here to discuss. The kids will also get to see some familiar dinosaur families while learning about species that are new to them. I think during adaptation related presentations, this formation lets us get into ecological niches and discuss how two Tyrannosaurids existed as did at least two species of Dromaeosaurids and a Troodonitd plus other predators including non dinos. That is a lot of hungry mouths so niche selection and adaptations become very important. THere is also a great diversity of herbivores in this formation. I love the Ceratopsians from this formation and the diversity gives my son a lot of artistic options. We currently have one tooth but by the time we present we will have a couple more I think. This allows us to present a few species and say the teeth are not diagnostic so the teeth could have belonged to one or more really cool looking horned dinosaurs. This also gives the kids knowledge that there other Ceratopsians besides Triceratops. This will also be the point where we introduce Dromaeosaurids. Raptors are just iconic and this formation gives us the chance to really hit on adaptations. We have a Saurornitholestes tooth and will soon have a Dormaeosaurid caudal vertebra. While not assigned specifically to Dromaeosaurus, the vert will presented that way so we can talk about the differences between the two raptors. Of particular interest is the larger skull, more robust teeth, and specific wear patterns on the teeth of Dromaeosaurus. We will also have a small tooth tip from a Tyrannosaur indet. The kids will love learning about other Tyrannosaurids and I will leave it to the kids to imagine which one it belonged to. The real owner of the tooth is not important. That two existed in this formation is what is important. They must have occupied different niches plus a lot of kids may think T-Rex was the only member of that family. The last fossil I know we will have from Judith River is one of my favorites. It is an Ankylosaurus tooth and thanks to some help from TFF members, I spotted this among a few Nodosaur teeth. In our inventory, this is Ankylosaurus indet. However, in every single dinosaur presentation we do this will be Zuul and it will be a rock star. We want the kids to understand that there are many new discoveries being made and there will be a lot of new dinosaur discoveries made by THEIR generation. Everything about Zuul will be cool to kids. It is the one of the most incredible fossils ever found, armored dinosaurs are just cool, and it even has a pop culture name that a lot of kids will recognize from Ghostbusters lol Only 5 fossils but we can do A LOT of quality education with these fossils. I also have a very clear idea of the next items to find from Judith River. #1 on that list is a Dromaeosaurus tooth. A tooth gives us the perfect way of illustrating the difference between the raptors. We have two more purchases to complete before I buy again so I will save up and in the spring I start searching for that tooth. I also would love to add a hadrosaur bone from this formation and eventually I will track down a frill piece. Anyway, here a couple of the fossils... Pic 1- our Saurornitholestes tooth. Not a great picture but a really nice tooth. Pic 2- the Dormaeosaurid indet vert. Not here yet but will be right around my B-day. Pic 3- the Anky tooth. It is just a cool tooth and Zuul is a great dinosaur to teach kids about so Zuul is what this tooth is for Fossils on Wheels. Our only fossil from an armored dinosaur.
  3. Nanotyrannus?

    I've been looking at this tooth labeled Nanotyrannus from the Lance Formation in Wyoming (scale is in cm) . Now, the photos aren't great but I'm sort of wondering if it really is Nanotyrannus. It isn't quite as rectangular as other nano teeth I've seen (though I'll readily admit that I haven't seen a lot) and seems less curved. Any thoughts?
  4. Tyrannosaurid Tooth ID

    Howdy, folks! So just thought I'd pop a thread up for a partial tooth in my collection. It was originally sold as "unknown - possible croc tooth" when I purchased it. I tried getting an ID on it a couple of years ago, but the lighting in the photos made serrations hard to see, and it was tough to distinguish small details.... So here's attempt #2 (with better pics)! Any confirmation of ID mucho appreciated. Locality: Hell Creek, USA (afraid exact location is unknown) Mesial view?: Distal view?: Cross section: Closer look at denticles:
  5. Tyrannosaurid indet.

    From the album My Collection

    Tyrannosaurid indet. (Likely Daspletosaurus horneri or Gorgosaurus sp.) Two Medicine Formation Browning, Montana
  6. My June expedition was super fun and interesting to see what I could find. I have lots of unknowns and lots of fossil material that others will be able to help id. Thanks in advance for all those that join the discussion and help me figure out my library of dinosaur fossils.
  7. Hello everyone. I saw this nice Albertosaurus tooth fragment online being sold for relatively cheap. I thought it had nice size,serrations and tip. It is from the Judith formation in Montana. Do you think it is worth considering? Or do you think I should keep my money. If I could get it a bit repaired and nicely reglue the fragments,It could be quite neat I think. It would be my first Tyrannosaurid in my collection (and my only for a long time). What do you think? Here are the 3 pictures I have. Thanks alot,Regards
  8. Tyrannosaurid Tooth?

    Hi folks! Thought I might try leaning on the expertise of the forum gurus - I've owned this tooth for a few years and would like to hear any opinions of what the specimen should be classed as. It was sold as Daspletosaurus Torosus, but I'm aware of how hard it can be to label Tyrannosaur teeth (or just leave them as 'indet'). The tooth originated from Alberta, Canada. As it isn't the clearest to see, the denticles (which are very fine and equal in size on both sides) on the anterior edge curve off to the right (viewing the tooth face on), whilst the posterior serrated line is straight. PS: Apologies for the quality of photos too...my phone doesn't enjoy photographing anything magnified.
  9. Wear facets, spalling and split carinae are typical features you see on Tyrannosaurid teeth that add character and mystery to these teeth. Here are two papers that examine these features. Wear Facets Lambe (1917) noted wear surfaces on the side faces of tyrannosaurid lateral teeth from the Red Deer River deposits of western Canada. He wrote “as the upper teeth closed outside those of the mandible any wear, not on the point, would result from the contact of the inner surface of the upper teeth with the outer surface of the lower ones.” Recent work, has, however, challenged this assertion, suggesting that the shapes, locations, and incidences of tyrannosaurid wear surfaces are not indicative of tooth−tooth contact (Farlow and Brinkman 1994; Molnar 1998; Jacobsen 1996, 2003). Here the paper reevaluates this evidence by examining wearstriations in tyrannosaurid lateral teeth in addition to the shapes and locations of their wear surfaces. Wear facets and enamel spalling in tyrannosaurid dinosaurs Blaine W. Schubert and Peter S. Ungar Acta Palaeontologica Polonica 50 (1), 2005: 93-99 app50-093.pdf Split Carina 11% of the teeth studied in the paper exhibited this trait. Trauma, aberrant tooth replacement, or genetic factors may have led to the development of split carinae. The paper concluded that although not conclusive genetic factors get the most support but additional study is needed. Other factors like nutrition may play a part but the paper points out is not testable. Pay walled Split Carinae on Tyrannosaurid Teeth and Implications of Their Development Gregory M. Erickson Pages 268-274 | Received 14 Jun 1993, Accepted 17 Jan 1994, Published online: 24 Aug 2 https://doi.org/10.1080/02724634.1995.10011229 From my collection
  10. 3.75" tyrannosaurid tooth. Indet.?

    Fossil tyrannosaurid tooth found last weekend. 2nd largest one I have found and largest in the area by at least an inch. Formation is belly river group. I believe i is out of dinosaur park formation layers and possibly mix of oldman and foremost formations. I'm thinking gorgosaurus or daspletosaurus???
  11. Tyrannosaurid Bone from Delaware

    A new unrecognized metartarsal from a tyrannosaurid in Delaware is discussed in this paper. It increases the diversity of tyrannosaurids in Appalachia which previously included, Appalachiosaurus montgomeriensis and Dryptosaurus aquilunguis. Fitting for our first state. Brownstein CD. (2017) A tyrannosauroid metatarsus from the Merchantville formation of Delaware increases the diversity of non-tyrannosaurid tyrannosauroids on Appalachia. PeerJ 5:e4123 https://doi.org/10.7717/peerj.4123
  12. Texas Teeth

    Here's some of my best Texas teeth. All personal finds except for the partial Tyrannosaurid tooth. The little red tooth on the bottom is also Mosasaur.
  13. Chiropractor discovers BC's first dino skull. Looks like a Tyrannosaurid. Pretty good find while on holiday http://www.cbc.ca/amp/1.4158748
  14. Interesting paper that supports reptilian looking tyrannosaurids From Abstract Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex, were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids (Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus), confirming that these large-bodied forms possessed scaly, reptilian-like skin. Body size evolution in tyrannosauroids reveals two independent occurrences of gigantism; specifically, the large sizes in Yutyrannus and tyrannosaurids were independently derived. These new findings demonstrate that extensive feather coverings observed in some early tyrannosauroids were lost by the Albian, basal to Tyrannosauridae. This loss is unrelated to palaeoclimate but possibly tied to the evolution of gigantism, although other mechanisms exist. http://rsbl.royalsocietypublishing.org/content/13/6/20170092
  15. Tyrannosaurus sp?

    Tyrannosaurus sp? from West Texas. No restoration or repair. 1 1/2".
  16. I searched the web and found only a reference to another thread that seem to say this was Tyrannosaurid indet but it seems to be some time back before Timurlenga was described as a species. My question is, is it possible this is timurlenga? Or does the Bissetky Tyraanosaurid sound a better fit?
  17. I bought this nice theropod tooth online and the seller told me that it was a Daspletosaurus from the Judith River Formation, Montana. While looking online for more info, I found a few people saying that some dealers lie about the genus of tyrannosaurid teeth (especially with Daspletosaurus) as they are hard to identify. Just wondering if anyone here can I.D. this tooth? Suggestions are much appreciated!
  18. Tyrannosaurid tooth

    Tooth of a Tyrannosaurid. This tooth belongs to either Albertosaurus, Gorgosaurus or Daspletosaurus. Note the wear facets on the top and medial side of the tooth.
  19. Its is found at the ili river basin, dzhungar alatau kazakhstan,
  20. Updated Jan 7, 2020 Collectors, online sellers and some dealers periodically ask me to help them in the identification of tyrannosaur type teeth. So I thought I would put together a guide from North America to help in identification. The following is the current understanding of Tyrannosauridae species described/known in North America with the stratigraphic unit where they are found: Albertosaurus sarcophagus : Horseshoe Canyon Formation Gorgosaurus libratus : Dinosaur Park Formation Gorgosaurus sp. or cf Gorgosaurus: Two Medicine Formation, Oldman Formation, Foremost Formation, Judith River Formation Daspletosaurus horneri : Two Medicine Formation Daspletosaurus torosus : Oldman Formation Daspletosaurus sp. or cf Daspletosaurus: Dinosaur Park Formation, Foremost Formation, Judith River Formation, Kirtland Formation Tyrannosaurus rex : Hell Creek Formation, Lance Formation, Frenchman Formation, Javelina Formation, Scollard Formation, Denver Formation, Nanotyrannus lancensis : Hell Creek Formation, Lance Formation cf Nanotyrannus : Frenchman Formation, Scollard Formation, Denver Formation, cf Tyrannosaurid : Aguja Formation, Kirtland Formation, Ojo Alamo Formation Aublysodon mirandus Premaxillary teeth, those without serrations. This dinosaur is considered nomen dubium and teeth ascribed to it belong to other Tyrannosaurs. Albertosaurus sarcophagus Probably the easiest to identify since its the only Tyrannosaurid described from the Horseshoe Canyon Formation. The most important item in acquiring one of these teeth is the provenance of where it was found. Alberta is not adequate to identify it. You need a specific locality like Drumheller or Tolman Bridge. BTW this is true for all the Tyrannosaurid's discussed in this topic. A disposition is also needed for all dinosaur teeth removed from Alberta. Gorgosaurus libratus (cf, sp.) The first step in identification is Provenance: you need to know State/Province along with the County (USA) or Locality (Canada) where the tooth was found. Differentiating isolated teeth between Gorgosaurus and Daspletosaurus is very difficult and in most cases its indeterminate. A paper that came out in 2005 which was authored by Phil Currie et al. studied isolated teeth from this period looking at tooth and serration morphology. Their conclusion was that "it is difficult to quantifiably distinguish these teeth reliably by taxon" . Therefore identifying them as Tyrannosaurid indet. is the easiest approach in those faunas that Gorgosaurus may be present. There is a quantitative process described in a new paper that may help which will be discussed later. Please note that lots of collectors would like to use size to differentiate these teeth from Daspletosaurus. However Gorgosaurus teeth can get quite large as seen in this photo of a Maxilla with one tooth which is over 3 inches and located in the back of this jaw. Daspletosaurus horneri, D. torosus (cf, sp.) The first step in identification is Provenance: you need to know State/Province along with the County (USA) or Locality (Canada) where the tooth was found. A paper that came out in 2005 which was authored by Phil Currie et al. studied isolated teeth from this period looking at tooth and serration morphology. Their conclusion was that "it is difficult to quantifiably distinguish these teeth reliably by taxon" . Therefore identifying them as Tyrannosaurid indet. is the easiest approach in those faunas that Daspletosaurus may be present. However if you are the proud owner of tooth around 4" its fair to say its probably from a Daspletosaurus. There is a quantitative process described in a new paper that may help which will be discussed later. Tyrannosaurus rex/ Nanotyrannus lancensis (cf, sp.) Whether your agree or disagree that Nanotyrannus is a valid taxon what is very clear to me is that we have two distinct morphologies of tyrannosaurid teeth at the very end of the cretaceous. I can say that because I have handled over 1000 teeth over the years ranging from 3 mm to 5 inches and two morphs are present in all ranges up to around 2 1/2 inches. Serration density through sampling I've done with teeth in my collection do not appear by itself to be a differentiator between these two morphologies. Density will change with size becoming less on larger teeth and can be the same with equivalent size teeth with both morphologies. DSDI (Denticle Size Difference Index) is also not a differentiator and through my sampling and Carr (2004) and indicates that DSDIs decrease in progressively larger specimens, that is, there are fewer mesial denticles per given unit length than distal denticles in large specimens and there are as many or more mesial than distal denticles in small specimens. Also, the DSDI among dentary teeth is higher than that in the maxilla, indicating that mesial denticles are smaller in the dentary than in the maxillary dentition. So how do you tell the difference between these two morphologies. Well if a tooth is larger than 2 1/2" and has bulk its clearly T rex, regardless of what the serrations say. It cannot be anything else. With small teeth since serrations density is not a differentiator the other characteristics of the tooth plays a key roll. I've found that maxillary teeth can be the most difficult to differentiate and a few teeth are just indeterminate, at least with me. The best way to distinguish between the two morphology the shape at the base, compression of the crown and tip and if there is a pinch at the base. Shape at the base T rex dentary teeth are oval at the base while Nano teeth are unique as tyrannosaurids and rectangular. However T rex maxillary teeth can be rectangular so you will have to determine if there is a pinch at the base a characteristic found on Nanotyrannus teeth Here are examples of the cross sections of couple small Rex teeth under 1 1/2 inch and Adult Nano's Tyrannosaurus rex Dentary teeth are oval Maxillary Teeth are rectangular Nanotyrannus Bases are rectangular and show a pinch on the sides. Profile of the teeth is another characteristic Nanotyrannus teeth are compressed, with a pointed tip T rex teeth are fat, with a rounded tip, often the serrations wrap around from the mesial to distal carina T rex Premaxillary Teeth can easily be confused with dentary D1 position. Here is a photo of how to determine what you have. Identifying Gorgosaurus and Daspeletosaurus Teeth using Dental Features A recent paper by Hendrickx et al. (Oct 2019) has provided us a way to try to identify certain teeth using dental features. Positional Daspletosaurus & Gorgosaurus teeth have distinct denticle features that can hopefully can be used to differentiate the species which currently does not exist. Together with @Omnomosaurus we are looking at studying this technique to determine if its a practical method for collectors to use for identification, obtain data on campanian tyrannosaurid teeth and try to understand if the results we are getting is any good? We will be using teeth from my collection and members for the study. @dinosaur man has a topic where a lot of member data will be collected. Step 1 The most critical part in using this process is knowing where the tooth sits in the jaw - Premaxillary, Mesial or Lateral Here is a photo of to help in determining its location Paper https://www.researchgate.net/publication/261630184_Morphometry_of_the_teeth_of_western_North_American_tyrannosaurids_and_its_applicability_to_quantitative_classification Step 2 DSDI (Denticle Size Difference Index) needs to be determined DSDI = MC / DC MC = Number of denticles per 5 mm on the mesial carina at mid-carina DC = Number of denticles per 5 mm on the distal carina at mid-crown Mesial Carina is on the outer curvature Distal Carina is on the inside curvature Step 3 1) If your tooth is from a lateral position in the jaw and your DSDI is <0.8 your tooth may be considered a Gorgosaurus or cf Gorgosaurus depending on the locality of where it was found. 2) If your tooth is from a Mesial position in the jaw and your DSDI is >1.2 your tooth may be considered a Daspletosaurus or cf Daspletosaurus depending on the locality of where it was found. Premaxillary Teeth 1) In my opinion all these teeth should be identified as "Tyrannosaurid indet" 2) The paper does make the following statement "In the young specimens of Daspletosaurus, the carinae of the premaxillary teeth are unserrated (TMP 1994.143.1; Currie, 2003) and show the beaded condition. My concern is that it does not specify what size young teeth are and its looking at TMP 1994.143.1 which is a Daspletosaurus sp in Dinosaur Park Fm. Do all Daspletosaurus premax teeth in other faunas have contain similar features? Gorgosaurus premax teeth are not mentioned. Study Currently 33 teeth from the collection of Troodon, Omnomosaurus, dinosaur man Localities included : Judith River Formation (18 teeth), Two Medicine Formation (13 Teeth), Dinosaur Park Formation (1 Tooth), One unknown Results: 1) None of the lateral teeth have had DSDI < 0.8 and could be described as Gorgosaurus 2) Three of the Mesial teeth had DSDI > 1.2 and could be described as Daspletosaurus 3) One of the Premaxillary teeth was not serrated but could not verify if it was a young tooth 4) So 9% of the population can be tentatively assigned Hendrickx et al paper https://palaeo-electronica.org/content/2019/2806-dental-features-in-theropods
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