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  1. Hi All, I'm new to this forum and thought I'd send over images of my theropod teeth plus one extremely impressive sauropod from Madagascar. Hope you like them! Paul
  2. Hello all, I’ve had this tyrannosaur tooth for a little while now, but haven’t been able to narrow down a species. I’m curious if it is possible to ID it any further. Would love to learn more. It was found in the Judith River Formation (Hill County, MT), and is ~13.5mm. Thank you all for your help in advance!
  3. This is a tooth that lets me doubt the label… It was sold as “Albertosaurus”. Provenance is Hell Creek Formation, Montana. But to my understanding there is no Albertosaurus in the HCF of Montana or am I wrong? The serration count is 3 per mm and 2.5 per mm. Has someone got an idea what it might be?
  4. Josh_irving

    Identifying Tyrannosaurid Tooth

    Hello Everyone, I bought this tooth nearly ten years ago as a Albertosaurus tooth from the Two Medicine formation, Montana, U.S.A. Whilst updating my labels I have learnt that Albertosaurus is not found in the Two Medicine Formation. As a result, i am asking if anyone can ID this tooth (i know it is very difficult or more likely impossible). I believe it is either a Distal Maxillary or a Distal Dentary tooth. The MC is 18 whilst the DC is 16 which gives it a DSDI of 1.125. The tooth is 2.90cm tall and the base of it is 1.22cm by 0.86cm. the link to some fairly high quality photos is: Tooth Id - Imgur thanks in advance, Josh
  5. Updated Nov 25, 2022 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 Western North America (US/Canada) to help in identification. The following is the current understanding of those Tyrannosaurids described/known with the stratigraphic unit where they are found. If I missed any let me know. Albertosaurus sarcophagus : Horseshoe Canyon Formation cf Albertosaurus indet: Wapiti Formation Gorgosaurus libratus : Dinosaur Park Formation Gorgosaurus sp. or cf Gorgosaurus: Two Medicine Formation, Oldman Formation, Foremost Formation, Daspletosaurus horneri : Two Medicine Formation Daspletosaurus wilsoni: Judith River Formation Daspletosaurus torosus : Oldman Formation Daspletosaurus sp. or cf Daspletosaurus: Dinosaur Park Formation Dynamoterror dynastes: Menefee Formation Tyrannosaurus rex : Hell Creek Formation, Lance Formation, Frenchman Formation, Scollard Formation, Denver Formation, (Trex fossils are also known from: Livingstone Fm, Laramie Fm, McRae Fm, Willow Creek Fm) Tyrannosaurus sp.: Javelina Formation, Ojo Formation Nanotyrannus lancensis : Hell Creek Formation, Lance Formation cf Nanotyrannus : Frenchman Formation, Scollard Formation, Denver Formation Thanatotheristes degrootorum : Foremost Formation Tyrannosaurid indet. (spp): Judith River Formation, Mesaverde Formation (Group), Fruitland Formation, Aguja Formation Teratophoneus curriei: Kaiparowits Formation Lythronax argestes: Wahweap Formation Nanuqsaurus hoglundi: Prince Creek Formation Tooth Identification 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. These teeth can get quite large from collection of SMM 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. wilsoni, 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, its reasonable to say that teeth over 4" are PROBABLY from a Daspletosaurus. There is a quantitative process described in a new paper that may help which will be discussed later. *****Since the Judith River and Two Medicine Formations fall within the range of all three of these species its going to be difficult to assign teeth to a specific species unless you know the age of the deposit it. Denver Fowler: "Hill County exposures are more easy to date because there we have the boundary between the upper Oldman Fm and the lower part of the Dinosaur Park Fm. Havre exposures were called Judith River Fm historically, but we should probably use Oldman & Dino Park now." And maybe ditto for those teeth found in the Belly River Group of Alberta. Denver Fowler "I expect that D. wilsoni is stratigraphically equivalent to the lower part of the Dinosaur Park Formation. At the moment this is based on the fact that the Judith in eastern Montana was deposited at the time when the WI seaway was receded at its maximum (in the Campanian)" Denver's response to my question on this subject. "There isn't currently any evidence for stratigraphic (time) overlap between the species. However, the 2Med and Judith River likely represent enough time such that it would be possible to find D. torosus in the Judith and both D. torosus and D. wilsoni in the 2Med." (Posted by Denver Fowler) Tyrannosaurus rex/ Nanotyrannus lancensis (cf, sp.) Whether you 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 two morphs are present in all ranges up to around 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 characteristic of the tooth plays a key role. 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 and the very anterior maxillary 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 both 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 to form a continuous carina Crown Height Ratios In the study I did, since nothing is published, with 30 Nanotyrannus teeth the average was 2.2 For Trex teeth the mean for Maxillary teeth is 1.75 and for Dentary its around 2 but all these can change depending on position Heterodonty in Tyrannosaurus rex: implications for the taxonomic and systematic utility of theropod dentitions Joshua B. Smith (2005) 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 sp. 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
  6. dongmin

    Deinosuchus tooth

    deinosuchus tooth good! The tooth was found in Chattahoochee River
  7. Along with an interest in Pennsylvanian fish diversity, I've also had an interest (like many others studying Paleontology) in the diversity of Dinosaur genera during the Cretaceous era (particularly the Theropod diversity in North America during the Maastrichtian period 72.1-66 Million years ago). Compared to the preceding Campanian period (83.6-72.1 Million years ago), I've noticed there is a slightly less number of known Tyannosauridae genera in Western North America (at the time a separate continent known as Laramidia). I've come up with a list of confirmed known and possible Tyrannosauridae genera during the Maastrichtian period in Western North America and Eastern North America. Eastern North America (at the time a separate continent known as Appalachia) Dryptosaurus Donoho Creek Formation Tyrannosauridae genera (possibly Appalachiosaurus) https://palaeo-electronica.org/content/2018/2123-appalachia-biogeography Chronister well (Ripley Formation) Tyrannosauridae genera http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&taxon_no=38606&max_interval=Cretaceous&country=United States&state=Missouri&is_real_user=1&basic=yes&type=view&match_subgenera=1 Western North America (Laramidia) Tyrannosaurus Rex Nanuqsaurus (Prince Creek Formation) Albertosaurus (more early Maastrichtian to around 68 Million Years ago) ?"Alamotyrannus" (could also be a species of Tyrannosaurus - ?Tyrannosaurus brinkmani) ?"Daspletosaurus sp. (Horseshoe Canyon Formation) (specimen CMN 11315) (more early Maastrichtian to around 68 Million Years ago) https://cdnsciencepub.com/doi/10.1139/cjes-2014-0072 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7079176/ I'm wondering if this is an accurate list, why is there a dip in Tyrannosauridae diversity in Eastern and Western North America after the Campanian (was it a result of the Deccan Volcanic eruptions in India around the same time, at least for Western North America (if this theory is current) the Native Western North American Tyrannosaur genera being outcompeted by the Eurasian ancestors of Tyrannosaurus Rex arriving in North America via a land bridge during the late Campanian Early Maastrichtian, or both), the status on the taxonomic validity of Alamotyrannus, was Nanuqusaurus present during the later part of the Maastrichtian, and did Albertosaurus and Tyrannosaurus Rex ever come into direct contact with one another?
  8. The two most prominent hypothesizes on the direct evolutionary origin of perhaps the most famous Theropod Dinosaur from the fossil record, Tyrannosaurus Rex (Tyrannosauridae, Late Cretaceous (68-66 Million Years ago)) are what I call the Laramidia and Asian Origins. The Laramidia origin (named after the region of the Western North America which was a separate Continent during most of the Late Cretaceous and home to a vast amount of dinosaurs including Tyrannosaurus rex) hypothesizes that Tyrannosaurus rex is the direct descendent of and evolved from slightly older North American Tyrannosaurids like Daspletosaurus (Tyrannosauridae, Late Cretaceous (79.5-74 Million Years ago)). Warshaw, Elías & Fowler, Denver. (2022). A transitional species of Daspletosaurus Russell, 1970 from the Judith River Formation of eastern Montana. PeerJ. 10. e14461. 10.7717/peerj.14461. https://www.researchgate.net/publication/365746599_A_transitional_species_of_Daspletosaurus_Russell_1970_from_the_Judith_River_Formation_of_eastern_Montana The Asian origin hypothesizes that Tyrannosaurus’s direct ancestor was a Tyrannosaurid from Asia. This supported by how closely related the Asian Tyrannosaurid Tarbosaurus (Tyrannosauridae, Late Cretaceous (70 Million Years ago)). This hypothesis further elaborates that a that the Asian Tyrannosaurids arrived in Western North America via a land bridge between what is now Eastern Russia and Alaska around 73-72 Million Years ago. On arrival, theses Asian Tyrannosaurids outcompeted and caused the extinction of most of the Native Tyrannosaur species of Laramidia (including Albertosaurus (Tyrannosaurid, Late Cretaceous (71-68 Million Years ago)), creating conditions allowing for the emergence of the genus Tyrannosaurus. Brusatte, Stephen & Carr, Thomas. (2016). The phylogeny and evolutionary history of tyrannosauroid dinosaurs. Scientific Reports. 6. 20252. 10.1038/srep20252. https://www.nature.com/articles/srep20252 Takasaki R, Fiorillo AR, Tykoski RS, Kobayashi Y (2020) Re-examination of the cranial osteology of the Arctic Alaskan hadrosaurine with implications for its taxonomic status. PLoS ONE 15(5): e0232410. https://doi.org/10.1371/journal.pone.0232410 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0232410 Both hypotheses have points that are supported by the fossil record, but still don’t fill all the gaps in answering the question of the direct origin of the genus Tyrannosaurus. There is however another hypothesis I have pondered over for at least the past few months which could fill in some (if not all) the gaps to this question. It is the Hybrid Speciation Origin hypothesis. The Hybrid Speciation Origin hypothesis basically states that after a land bridge formed between Eurasia and Laramidia during the Late Campanian stage of the Cretaceous (73-72 Million Years ago) and the Asian Tyrannosaurids arrived in Laramidia, certain individuals of a Asian Tyrannosaurid genus breed with a species of a genus of Native Laramidia Tyrannosaurid (likely a direct descendent of Daspletosaurus). Enough of these inter-genus breeding events occurred that a new Tyrannosaurid genus distinct from its parent species (and genuses) emerged around 68 Million Years ago, Tyrannosaurus. I will admit this would be extremely difficult to prove, but I do believe it could be a valid hypothesis. It corroborates the many similarities in skeletal structure Tyrannosaurus shares (and how closely related it is phylogenetically) with the Asian Tyrannosaurid Tarbosaurus and the skeletal structure similarities and general body shape it shares with Daspletosaurus. Image Credit: https://www.nature.com/articles/srep20252 Brusatte, Stephen & Carr, Thomas. (2016). The phylogeny and evolutionary history of tyrannosauroid dinosaurs. Scientific Reports. 6. 20252. 10.1038/srep20252. https://www.nature.com/articles/srep20252 Warshaw, Elías & Fowler, Denver. (2022). A transitional species of Daspletosaurus Russell, 1970 from the Judith River Formation of eastern Montana. PeerJ. 10. e14461. 10.7717/peerj.14461. https://www.researchgate.net/publication/365746599_A_transitional_species_of_Daspletosaurus_Russell_1970_from_the_Judith_River_Formation_of_eastern_Montana Stein, Walter W.; Triebold, Michael (2013). "Preliminary Analysis of a Sub-adult Tyrannosaurid Skeleton from the Judith River Formation of Petroleum County, Montana". In J. Michael Parrish; Ralph E. Molnar; Philip J. Currie; Eva B. Koppelhus (eds.). Tyrannosaurid Paleobiology. Bloomington: Indiana University Press. pp. 55–77. Currie, P.J. (2003). Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada. Acta Palaeontologica Polonica 48 (2): pp. 191–226. https://www.app.pan.pl/archive/published/app48/app48-191.pdf I am interested in how the tyrannosaurid species Nanuqusaurus (Tyrannosaurid, Late Cretaceous (70-68 (likely also to 66) Million years ago), the Daspletosaur Tyrannosaurid specimen RMDRC 2002.MT-001 “Sir William”, and the Tyrannosaurid specimen CM 9401 could factor into the validity of the hybrid speciation hypothesis. I hold no illusions in thinking this hypothesis is not going to be controversial. But I do think it could be semi plausible. What do you guys think?
  9. Dino Dad 81

    Albertosaurus?

    Hi all, Wondering if this checks out as Albertosaurus. From the Horseshoe Canyon formation in Drumheller, Alberta, Canada CH: 33.1mm CBL: 16.1mm CBW: 10.5mm Mesial Serration Density: 4/mm Distal Serration Density: 3/mm
  10. Dino Dad 81

    Albertosaurus?

    Hello again--thanks so much for all the help lately! Is it likely that this is from Albertosaurus and not another tyrannosaurid if all we know about it is that it's from Alberta, CA? What additional info is needed to make such a call?
  11. Hi, guys. Does anyone have some high-quality images of Albertosaurus sarcophagus skulls (or maxilla /dentary)? please. and the following images were my sharing, which I found on the internet. Thanks for your guys' sharing. have a lovely day guys.
  12. AranHao

    Albertosaurus

    This is an Albertosaurus tooth in the matrix. Below this matrix is a hadrosaurs rib, the fossils comes from Drumheller ,Alberta, Canada There are special patterns on the enamel. Any insight on this would be greatly appreciated.
  13. musicnfossils

    Albertosaurus Tooth in Bone

    Looking at buying this piece, curious if it’s a tooth stuck in bone or a jaw piece. Albertosaurus tooth from the horseshoe canyon fm. Sorry had nothing on me to measure size.
  14. Hello I am looking for help to identify these two teeth. I was told that they are T. rex but I feel either one of both are Albertosaurus but not 100% sure how to tell. I have included many photos and measurements. Both teeth are from the Hell Creek Formation. The first tooth and the shorter one is measures 2" long by 1" wide The second and longer tooth measures 2 1/4" long by .3/4" wide. Any information would be appreciated.
  15. Rikache

    Albertosaurus and T-Rex teeth?

    Hi there everyone! I’ve recently been looking for a tyrannosaur tooth to add to my collection and I came in contact with a very nice seller who’s in possession of two theropod teeth. The main tooth I have questions about is the “Albertosaurus” tooth as that one seems to be the one which would be easiest to ID. I was wondering if it was truly an Albertosaurus tooth or if there was any other identification that could be given to it. The other tooth, the “Tyrannosaurus Rex” tooth, only has one picture and seems to be in two pieces. I’m aware that the single picture makes it near impossible to properly identify, but I’d greatly appreciate it if you guys could still give it a shot and give a rough guess. Since it’s somewhat small I reckon it could be a Nanotyrannus specimen, though I’m aware that a view of the bottom of the tooth would be somewhat necessary to identify it as such. Thank you everyone for your help. I’ve thoroughly enjoyed my time here in this forum and I can’t wait to keep learning and sharing!
  16. Hey! These are just a few of the bones I found recently which were all found near each other in horseshoe canyon AB. I found what I believe to be albertosaurus teeth and a piece of a hadrosaur jaw as well with them which makes me assume they are from one of those two species. However, I need help identifying which species each one might be from and what part of the dinosaur they are. If you need measurements I'm happy to post pics next to a ruler!
  17. Wurm

    Tooth Id

    Hey! Both of these teeth were found in the horseshoe canyon in the same place. I was thinking Albertosaurus but I don't know(They are serrated if you couldn't tell from the photos). Any ideas? (sorry for the low quality images)
  18. Top Trilo

    Tyrannosaur tooth ID

    I bought this tyrannosaur tooth a while back and it says it’s a albertosaurus, gorgosaurus, or daspletosaurus. Is there anyway to narrow it down any further? It says it was found in the Judith river formation of eastern Montana and it measures just over an inch. Any and all help is appreciated.
  19. Scylla

    Baby Tyranosaurs Discovered

    Baby tyranosaur fossils found https://www.livescience.com/baby-embryonic-tyrannosaur-fossils.html
  20. musicnfossils

    Albertosaurus?

    I seen multiple hell creek fm teeth for sale labelled as “Albertosaurus”, though I’m pretty sure I’ve read that the only way to confirm it’s Albertosaurus is for it to be found around the Drumheller area, specifically horseshoe canyon. Is this true, making the teeth simply indeterminate tyrannosaurids or are the fossils of this animal found elsewhere? Thanks.
  21. Alex Eve

    Albertosaurus tooth placement

    Hello. I found this 7.5 cm Albertosaurus tooth in the Bleriot Ferry area of the Horseshoe Canyon Formation last month. Based on the wear mark on the end, whereabouts would the tooth be placed within the mouth? (top or bottom?). Is it possible to tell?
  22. Hi I decided to make this since the new Tyrannosaur from Alberta’s Foremost Formation, Thanatotheristes deerootorum has just been named and described. Enjoy!! Tyrannosaur bearing Formations in Canada: Formations in Alberta but most of the Formations on my list are I Alberta anyway. Horseshoe Canyon Formation 74-68 million years ago, Alberta: Albertosaurus sarcophagus, possibly Daspletosaurus sp. but no compelling evidence so far. Oldman Formation 78.2-77 million years ago, Alberta: Daspletosaurus torosus, Gorgosaurus sp. Foremost Formation 80.5-78.2 million years ago, Alberta: Thanatotheristes deerootorum, possibly Gorgosaurus sp. Milk River Formation 84.5-83.4 million years ago, Alberta: Tyrannosaur. indet could be a species of Thanatotheristes, possibly Gorgosaurus sp. Scollard Formation 68-66 million years ago, Alberta: T. rex, possibly Nanotyrannus Formations in British Columbia: Wapiti Formation 76.8-70 million years ago, Alberta, British Columbia: Unknown Albertosaurinae either Gorgosaurus or Albertosaurus, possibly Daspletosaurus sp. Tumbler Ridge 135-74 million years ago, British Columbia: Tyrannosaur. indet Formations in Saskatchewan and Manitoba: Dinosaur Park Formation 77-75.5 million years ago, Alberta, Saskatchewan: Daspletosaurus sp., Gorgosaurus libratus Frenchmen Formation, 68-66 million years ago, Saskatchewan: T. rex, possibly Nanotyrannus Bearpaw Formation 75-72 million years ago, Alberta, Saskatchewan, Manitoba: Daspletosaurus sp. one specimen from Daspletosaurus sp. that drowned. For now these are all the Tyrannosaurs known from Canada. No Eastern Tyrannosaurs in Canada yet either but maybe someday. I will also update this and add as more information comes available.
  23. dinosaur man

    Unknown tyrannosaur

    Hi I found this and am wondering is this a new species of tyrannosaur I don’t think it’s albertosaurus libratus because it is in a collection with gorgosaurus libratus and albertosaurus sarcophagcus so if it was albertosaurus libratus there would not be any specimens named gorgosaurus libratus there are other specimens then just this tooth too any information? Thanks.
  24. Raulsaurus

    Albertosaurus tooth

    Hello!!! I have been offered this tooth. The seller says it is from Albertosaurus and comes from Montana. Without restoration, they have only used glue. What do you think? Thank you very much and sorry for the quality of the photos but the seller does not know how to make them better ...
  25. Dracarys

    Therapod Tooth - Albertosaurus?

    This one inch robust tooth came out of Hell Creek Montana and labeled as Albertosaurus. Does that appear correct? Can one tell the difference from other therapods in the region? Thank you in advance
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