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Found 25 results

  1. Hello, Like some of you knows I'am a portuguese collector who also collaborates with the Lourinha museum. In 2018 I found a pterosaur jaw and I donated to the museum and that fossil this year originated a new specie. The 𝑳𝒖𝒔𝒐𝒈𝒏𝒂𝒕𝒉𝒖𝒔 𝒂𝒍𝒎𝒂𝒅𝒓𝒂𝒗𝒂. I attached the pdf of the publication (peerj-16048.pdf). who done this study was a Portuguese American - Alexandra Fernandes. The jaw I found:
  2. Alvrr.0

    What genus is this Ammonite?

    So i found this Ammonite in one of my trips to a late jurassic/early cretaceous marine formation. I posted this same specimen but without preparation and they tell me that is impossible to know without the center area or the inner whorls. Now I prepped this Ammonite and the ribs on the inner whorls are visible. If anybody can tell about the genus or species of this Ammonite i'll be very greatful. Thanks!
  3. The Tyrannosaur Dinosaurs (Tyrannosauroidea) inhabited North America from 152 Million Years ago during the Late Jurassic era up until 66 Million Years ago during the Late Cretaceous era. https://www.app.pan.pl/article/item/app20110141.html However, there is a relatively large geologic gap between the time of the Late Jurassic to the Santonian-Campanian stages of the Cretaceous (when the the oldest known Tyrannosaurid Lythronax (Late Creteaceous, 81.9-81.5 Million Years ago) emerged) in terms of the number of Tyrannosauroidae confirmed in North America. However, this doesn't mean they were completely absent from the Continent. Rather, they remained small to mid sized predators under the shadow of Large Carnosaurs up until the Cenomanian-Turnonian extinction event 93-94 Million years ago, which the tyrannosaurs filled the role of Apex Predator in most terrestrial ecosystems by the Campanian stage of the Cretaceous. The Tyrannosaur geologic gap between the Late Jurassic and Santonian Cretaceous is also not completely empty and several confirmed Tyrannosauroidea are known from this time period in North America. I've created a list of known Tyrannosauroidea species and specimens from the Aptian-Santonian Cretaceous of North America which I would like to share on the fourtm (let me know if there are any examples I'm missing or should add): Unnamed Cloverly Formation Tyrannosauroid (Tyrannosaur – Cloverly Formation, Wyoming, US, North America) (Early Cretaceous, 108 Million Years ago) (Based on Specimen FMNH PR 2750, likely grew up to 1.2 meters (3.9 feet) in length) https://www.tandfonline.com/doi/abs/10.1080/08912963.2010.543952 https://www.researchgate.net/profile/Lindsay- Zanno/publication/229287579_On_the_earliest_record_of_Cretaceous_tyrannosauroids_in_western_North_America_Implications_for_an_Early_Cretaceous_Laurasian_interchange_event/links/0fcfd50089dd8f3955000000/On-the-earliest-record-of-Cretaceous-tyrannosauroids-in-western-North-America-Implications-for-an-Early-Cretaceous-Laurasian-interchange-event.pdf Unnamed Wayan Formation Tyrannosauroid (Tyrannosaur – Wayan Formation, Idaho, US, North America) (Early Late Cretaceous, 100.6-97.8 Million Years ago) (Based on Specimen IMNH 2251/53975, grew up to 1.2 meters (3.9 feet) in length) https://bioone.org/journals/journal-of-paleontology/volume-96/issue-6/jpa.2022.42/A-partial-tyrannosauroid-femur-from-the-mid-Cretaceous-Wayan-Formation/10.1017/jpa.2022.42.full Unnamed Lewisville Formation Tyrannosauroid (Tyrannosaur - Woodbine Group Lewisville Formation, Texas US, North America) (Late Cretaceous (100-95 Million Years ago)) (Based on Specimens DMNH 2013-0701701 and SMU 77218, grew up to 2.7-4.8 meters (8.8-15 feet) in length) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8796713/ Moros intrepidus (Tyrannosaur – Cedar Mountain Formation, Utah, US, North America) (Early Cretaceous (96.4 Million Years ago)) (Grew up to 1.2 meters (3.9 feet) in length) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6385174/ Suskityrannus hazelae (Tyrannosaur – Moreno Hill Formation, New Mexico, US, North America) (Early Cretaceous, 93.5-89.3 Million Years ago) (grew up to 3 meters (9.8 feet) in length) https://www.pure.ed.ac.uk/ws/files/82474043/82473554._Brusatte._AAM.pdf
  4. As a freshmen in College, I did a little extra credit report for my geology class about a controversial topic - Tyrannosauroidea diversity in the Southern Hemisphere during the Jurassic-Early Late Cretaceous periods. I was quite surprised at the amount of specimens I found. This diversity likely was the result of an early spread of the early tyrannosaur group Pantyrannosauria into Africa, Eurasia, and North America during the Jurassic and diversified once the land connecting these continents spread out more. Most of these species lived during the Early Cretaceous, though one or two exceptions might have lasted into the Early Late Cretaceous. I've created a list of known of the species and specimens which I would like to share on the forum (let me if there are any examples I'm missing or should add): South America Santanaraptor (Romualdo Member of the Santana Formation) (Early Albian, Cretaceous period 112.6-109.0 million years ago) Specimen: MN 4802-V (partial skeleton) http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=67712 Tyrannosauroidea indet. (Rio do Peixe Group of the Sousa Formation) (Berriasian to the Berriasian, Cretaceous period 145.5-130.0 million years ago) Specimen: NA http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=58791 https://www.researchgate.net/publication/309717524_As_localidades_com_rastros_fosseis_de_Tetrapodes_na_America_Latina Tyrannosauroidea indet. (Serra da Galga Member of Marília Formation) (Late Maastrichtian, Cretaceous Period, 70.0-66.0 million years ago) Specimen: CPP 449 (partial tooth) https://www.researchgate.net/publication/270524259_Theropod_teeth_from_the_Marilia_Formation_late_Maastrichtian_at_the_paleontological_site_of_Peiropolis_in_Minas_Gerais_State_Brazil (above paper initially described specimen, identification as possible Tyrannosauroidea in science direct paper) https://www.sciencedirect.com/science/article/abs/pii/S0031018220303151 Africa (Madagascar) Tyrannosauroidea indet. (Isalo Illb Formation) (Bathonian, Jurassic period 167.7-164.7 million years ago) Specimen: MSNM V5819 (partial tooth) http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=55391 https://www.researchgate.net/publication/257651210_First_description_of_theropod_remains_from_the_Middle_Jurassic_Bathonian_of_Madagascar Australia Timimus hermani (Otway Group of Eumeralla Formation) (Late Aptian, Cretaceous period 122.5-109.0 million years ago) Specimens: NMV P186303 (limb: left femur), NMV P186323 (limb: left femur of juvenile individual), QM F34621 (Pedal phalanx III-1) http://www.paleofile.com/Dinosaurs/Theropods/Timimus.asp http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=57099 Tyrannosauroidea indet. (Otway Group of Eumeralla Formation) (Late Aptian, Cretaceous period 110.0 million years ago) Specimen: NMV P186069 (Pubis bone) Possible Specimen: ?NMV P186046 (Pubis bone) https://www.researchgate.net/publication/42589187_A_Southern_Tyrant_Reptile https://www.sciencedaily.com/releases/2010/03/100325143045.htm
  5. WOW a eureka moment..... a publication using specimens in private collections...so It can be done and should be done. My hats off the the authors and hopefully it sets off a new standard for publications. One of the authors is well known paleontologist Eric Buffetaut Abstract: Dinosaur remains found at the Vaches Noires cliffs (Calvados, Normandy) have usually been discovered by amateur palaeontologists. The bones come from carcasses which drifted away from a nearby land (Armorican Massif) during the upper Callovian and lower Oxfordian. Most of these bones belong to private collections and are hardly accessible. Consequently, many of these bones were never described. Thus, and for the first time, private and public collections are gathered to obtain a global vision of theropod remains from the Vaches Noires cliffs Excerpts from the paper "they are essential for the study of theropod diversity from the Vaches Noires Cliffs, even if they are isolated and their precise stratigraphic origin is often unknown" "The aim of this study is to gather and describe bones from 6 different collections, most of which are private, and to provide new insights on known specimens" Wow again.. getting a good understanding of the fauna is more important than putting up walls on why not...nice job authors it would be nice to see that in North America where a few of our paleontologists even frown at looking at private material. https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/g2022v44a12.pdf
  6. sharkysaurus

    What is this fossil?

    I found these two neat little fossils in La Junta, Colorado. I'm not sure what they are but I have two guesses what they might be: barnacles or fish scales. I think it's from the Morrison formation but I'm not 100% sure! Any help would be appreciated
  7. rodrex

    Talbragar plant or animal?

    Hi All, Anyone got an idea of if this is a fossil plant or animal? Cheers R
  8. Paper describes a large theropod from Uruguay represented by isolated teeth which resemble Ceratosaurus. I dont have access to this paper but it will be interesting to see the multvariate analysis results and be able to compare these teeth to those found in Portugal. What is interesting in the highlights is that they propose that the spinosaurid Ostafrikasaurus crassiserratus from Tanzania should be referred as a ceratosaurid theropod. Paywalled: https://www.sciencedirect.com/science/article/abs/pii/S0895981120303242
  9. Paper describes a new Jurassic carcharodontosaurian taxon, Lusovenator santosi, gen. et sp. nov. based on the reevaluation of previously described specimens from the Lusitanian Basin, Portugal. No dentary material was found For those not members of SVP its paywalled, https://www.tandfonline.com/doi/full/10.1080/02724634.2020.1768106
  10. I have found this crinoid ossicle from the Morrison Formation seems to be agatized alot like the bone from the formation does anyone know of any others found from the Morrison? have looked online but cant find anything even articles talking about it.
  11. Peat Burns

    Polish Ammonites

    Looking for assistance with the identification of these ammonites from Poland (either Niegowoniec or Odrodzieniec). Age is late Jurassic; Oxfordian. Orthosphinctes? Perisphinctes? The best that I can tell, the ribs on the big one are only bifurcate. Anyone have an idea from which formation they may have come? @Ludwigia
  12. Archie 00 00

    What fossil is this?

    It was found on a beach in conglomerate rock in Wenderholm Regional park near Orewa above Auckland in New Zealand. it is 20mm long and 8mm wide
  13. Troodon

    New Stegosaur from Portugal

    Paper describes a largely complete specimen of Miragaia longicollum discovered in 1959 in Atouguia da Baleia, Peniche, Portugal, consisting of both anterior and posterior portions of the skeleton. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0224263
  14. Ludwigia

    Split Shift

    I worked another split shift today, so I decided to use the 4 hours in between to visit the site in the ditch at the side of the road in the Danube valley once again. No sense in driving home and back again when your tools are anyway in the trunk. Rain had been forecast for the afternoon, but it looked ok for the time being, so off I went. It's about a 3/4 hour drive and everything was looking good until about 15 minutes before arrival when suddenly over the last hill there were dark clouds with even more darkness below them looming on the horizon. Good thing I brought my raincoat and rubber boots. To make things even more complicated, it turned out that the road to the site was blocked off only about a half a kilometer away from it, so I had to turn around , detour back up the hill and down another road to get there, which cost me about another 20 minutes. That wasn't so bad though, since it was pouring with rain at that point, so I was wondering how long I was going to hold out anyway. As it turned out to my luck, the rain pretty well let up just as I arrived, so I thanked my lucky stars and walked down the road to the new spot I'd discovered about a month ago. I remembered to take my camera this time () so here it is. I'd been here already twice, so you can probably see that I've been working at getting that layer of limestone blocks removed. That's where the fossils are sitting, or rather, lying. So I continued on for about a half an hour in the drizzle, but then the rain started getting stronger again, then it started getting serious and after another 10 minutes it was pouring down in buckets and getting rather uncomfortable. No chance to take out the camera again. At least I had managed to extricate a few ammonites, so I wrapped them up quickly and headed back to the car and thence back to a couple more hours work of another kind. These things prep up pretty quickly, so I got them done already this evening. Actually there wasn't all that much worth keeping in the end, but at least these 2 turned out ok. Taramelliceras sp. 6.5cm. Ataxioceras sp. 7cm.
  15. These finds were reported a while back and this paper describes the finds. These two partial skeletons from Montana represent the northernmost occurrences of Stegosauria within North America ever recovered from the Morrison Formation http://app.pan.pl/article/item/app005852018.html
  16. Many of us collect material from the Morrison Formation especially teeth and claws. Not much is published to help us identify these items but this new paper gives us some insight into a new Troodontid that includes teeth and claws, Hesperornithoides miessleri https://peerj.com/articles/7247/ The serrations on the mesial carinae of maxillary teeth are smaller than the distal serrations as in basal dromaeosaurids. Mesial serrations are restricted to the apical third of the crown and appear absent in some teeth. Serrations are small (5.5 per mm distally)
  17. A new sauropod-related paper is now available online: Philip D Mannion, Paul Upchurch, Daniela Schwarz, Oliver Wings; Taxonomic affinities of the putative titanosaurs from the Late Jurassic Tendaguru Formation of Tanzania: phylogenetic and biogeographic implications for eusauropod dinosaur evolution, Zoological Journal of the Linnean Society, , zly068, https://doi.org/10.1093/zoolinnean/zly068 Giraffatitan, Tornieria, and Dicraeosaurus are the best-known sauropods from the Tendaguru Formation, but the paper by Mannion et al. (2019) provides new insights into non-diplodocoid, non-brachiosaur sauropod diversity in Tendaguru Hill by assigning the long-enigmatic sauropod Tendaguria to Turiasauria, and formally recognizing a set of tail vertebrae previously assigned to Janenschia as the first mamenchisaurid from Africa, bearing the new binomial Wamweracaudia keranjei. Given the placement of Janenschia outside Neosauropoda, and the turiasaur and mamenchisaurid classifications of Tendaguria and Wamweracaudia respectively, it is quite apparent that more than one clade of non-neosauropod sauropods existed in East Africa during the Late Jurassic.
  18. DD1991

    New choristodere from China

    A new paper you may find interesting: Ryoko Matsumoto, Liping , Yuan Wang & Susan E. Evans (2019). The first record of a nearly complete choristodere (Reptilia: Diapsida) from the Upper Jurassic of Hebei Province, People's Republic of China. Journal of Systematic Palaeontology (advance online publication) doi:Â https://doi.org/10.1080/14772019.2018.1494220 https://www.tandfonline.com/doi/full/10.1080/14772019.2018.1494220 Coeruleodraco is significant because it is the most complete Jurassic choristodere, considering that the exact relationships of Choristodera to other diapsids have remained contentious to this day given the dearth of early choristoderes. I know that the choristodere placement of Pachystropheus by Storrs and Gower (1993) has been questioned in recent papers due to the lack of skull remains, which preserve some diagnostic choristodere characters, and Lazarussuchus was considered the most primitive choristodere, a late-surviving basal one, until new material by Matsumoto et al. (2013) showed it to be more advanced than Cteniogenys.
  19. Ramon

    Fish tail?

    Hi, I went to the Tamazunchale area for Christmas break, and I bought this fossil from a local collector. He told me it was from some sort of aquatic animal. The sediments from the area are from the Pimienta, Santiago, and Taman formations. They represent Late Jurassic marine environments. Could this be a caudal fish fin (fish tail), or something else. I though it resembled part of a feather, but since they are marine sediments I doubt it.
  20. I periodically get asked about theropod teeth, so this is what I know. If you have additional tooth related information please pass it on since very little is known or published. Tanycolagreus topwilsoni The holotype included a fragmented skull with one premaxillary and two lateral teeth. Unfortunately, the teeth were crushed with no visible serrations so it's unknown how to describe them. Holotype skull Koparion douglassi Oldest known Troodontid and only known from a single maxillary tooth. Pictures says it all. A tooth taxon! Scale: A 1 mm, B-F 100 micrometers Chure, D. J. (1994). "Koparion douglassi, a new dinosaur from the Morrison Formation (Upper Jurassic) of Dinosaur National Monument; the oldest troodontid (Theropoda: Maniraptora)." Brigham Young University Geology Studies, 40: 11-15 Hesperornithoides miessleri A new Troodontid. The serrations on the mesial carinae of maxillary teeth are smaller than the distal serrations as in basal dromaeosaurids. Mesial serrations are restricted to the apical third of the crown and appear absent in some teeth. Serrations are small (5.5 per mm distally). The teeth are labiolingually compressed, and the enamel shows no trace of longitudinal grooves. Unfortunately the paper does not identify the sizes of these teeth. Distal Serration Density 5.5/mm FABL: around .45 https://peerj.com/articles/7247/ Coelurus fragilis Known from a fairly complete skeleton however there is a question if the dentary, below, belongs to the skeleton. No teeth were recovered and cannot find any additional information on teeth. Ken Carpenter recently responded to my inquiry about these teeth. He stated that we have no teeth from this dinosaur. Teeth have been called Coelurus because they are small but there is no proof of association Carpenter, K., Miles, C., and Cloward, K. (2005). "New small theropod from the Upper Jurassic Morrison Formation of Wyoming." in Carpenter, K. 2005. The Carnivorous Dinosaurs, Indiana University Press: 23-48 Ornitholestes hermanni Skull with both mandibles are part of the holotype. Osborn et. al (1917) paper just comments that the teeth are small and feeble. Carpenters book mentions that the skull is presently being studied by Mark Norell. C. Hendrickx 2019 paper shows some data on these teeth which I present here, 11 teeth were included in this study. Although very little is known with these teeth here is some data taken from AMNH holotype skull. Looks like the serrations are extremely fine. Maxillary teeth CH range from: 3.1 to 6.5 mm Dentary teeth CH range from: 3.9 to 5.6 mm Crown Height Ratios : 1.5 to 2.3 Crown Base Rations : 0.52 to 0.8 Interdental Sulci: Absent Transverse Undulations: Absent Serration density : Distal serrations were present on two teeth: a Maxillary Tooth 50/ 5/mm and Dentary Tooth 60/ 5mm Carpenter, K., Miles, C., and Cloward, K. (2005). "New small theropod from the Upper Jurassic Morrison Formation of Wyoming." in Carpenter, K. 2005. The Carnivorous Dinosaurs, Indiana University Press: 23-48 Reconstructed Skull AMNH Osborn, Henry Fairfield (1917). "Skeletal adaptations of Ornitholestes, Struthiomimus, Tyrannosaurus". Bulletin of the American Museum of Natural History. 35 (43): 733–771. hdl:2246/1334. Allosaurus fragilis (updated 6/19/22) Very little is published to aid in identification of these teeth. A recent paper by C. Hendrickx provided information on 60 teeth included in his study that I present in this edit. The following information is needed to help identify these teeth From Study: Premaxillary Positions: Serration Density: DSDI: 0.83 to 1.05 (Average : 0.98) Distal Density: 9.5 to 12.5 / 5 mm (Average : 10.3/ 5mm) Mesial Density: 8.3 to 11 .3 / 5 mm (Average : 10.1/ 5 mm) Other characteristics: Transvers Undulations: Can be present Interdental Sulci: Can be present Maxillary Positions: Serration Density: DSDI: 0.8 to 1.1 (Average : 0.95) Distal Density: 10 to 17.5 / 5 mm (Average : 12.5/ 5mm) Mesial Density: 9.5 to 14.0 / 5 mm (Average : 11.9/ 5 mm) Crown Height Ratio CH / CBL : 1.7 to 2.2 (Average : 2.1) Crown Base Ratio CBW / CBL : 0.37 to 0.8 (Average : 0.57) Other characteristics: Transvers Undulations: Can be present Interdental Sulci: Can be present Dentary Positions: Serration Density: DSDI: 0.91 to 1.3 (Average : 1.08) Distal Density: 10 to 13.75 / 5 mm (Average : 12.0/ 5mm) Mesial Density: 10 to 16.25 / 5 mm (Average : 13.1/ 5 mm) Crown Height Ratio CH / CBL : 1.8 to 2.5 (Average : 2.2) Crown Base Ratio CBW / CBL : 0.7 to 1.1 (Average : 0.86 ) Other characteristics: Transvers Undulations: Can be present Interdental Sulci: Can be present Unknown Positions: Serration Density: DSDI: 0.87 to 1.4 (Average : 1.07) Distal Density: 9 to 13.5 / 5 mm (Average : 11.4/ 5mm) Mesial Density: 8.8 to 17.5 / 5 mm (Average : 11.9/ 5 mm) Crown Height Ratio CH / CBL : 1.75 to 2.3 (Average : 2.2) Crown Base Ratio CBW / CBL : 0.46 to 1.1 (Average : 0.73 ) Other characteristics: Transvers Undulations: Can be present Interdental Sulci: Can be present Base shape can assist in identification. They can be J shaped The morphologically space occupied by Allosaurus is also seen by Ceratosaurus Poster with these illustrations Testinet.al.2011Poster.pdf cf Aviatyrannus Zone 2 South Dakota Not much is known on the teeth, its a tyrannosauroid Stokesosaurus clevelandi Zone 5 Utah late Kimmeridgian-early Tithonian Not much is known on the teeth, its a tyrannosauroid Saurophanganax maximus Zone 5 Oklahoma late Kimmeridgian- early Tithonian Allosaurid - might be an adult Allosaurus- teeth should be the same as one Torvosaurus Ceratosaurus Marshosaurus Reconstruction Skull of Marshosaurus from Utah Museum of Natural History. So you can see variation of the teeth in jaw
  21. Ludwigia

    Gravesia gigas ( Zieten 1830)

    From the album: Late Jurassic Ammonites from Southern Germany

    16cm. Late Jurassic, Tithonian, hybonotum zone. From a quarry in Emmingen-Liptingen.
  22. Ceratosaurus is one of my favorite Jurassic theropod Dinosaurs found in the Morrison Formation. Teeth of this and other theropods are commonly sold through online Dealers, Auction Houses and at Fossil shows. Just because a site/dealer sells Jurassic material does not guarantee the are accurately identified. Variation of the teeth in the jaw also adds to the complexity. Isolated teeth from the Morrison Formation are very difficult to diagnose and all require an understanding of additional characteristics than normal, in hopes of properly identifying them. Some publications describe the anterior teeth which is shown below.. This Latest edit is driven by C Hendrickx 2019 paper which shows some data on these teeth which I present in this edit. The following information is needed to identify these teeth: 1)Photo of tooth all sides and base and one of the mesial edge 2)Serration density of both edges, 5 mm wide at midline 3)Dimensions: CBL, CBW, CH 4)Locality: State and County Premaxillary Position (From Morrison Fm) (Data from 10 Teeth Hendrickx study) Crown height ratio CH÷CBL CHR : 1.2 to 1.9 (Avg 1.7) Crown base ratio CBW÷CBL CBR : 0.57 to 0.78 (Avg 0.66) Serration Density: DSDI 0.9 to 1.8 (Avg 1.35) Distal : 7 to 9 / 5 mm Mesial: 9 to 12.5 / 5 mm Other Characteristics Cross-section base : Subcircular Mesial Carina NOT reaching the base in most crowns Lingual grooves (flutes) are diagnostic and on the lingual side only. Transverse Undulations: May be present on the lingual side Interdental Sulci: Weak to absent Lateral Dentary Positions (From Morrison Fm) (Data from 9 Teeth Hendrickx study) Crown height ratio CH÷CBL CHR : 1.7 - 1.9 (Avg 1.8) Crown base ratio CBW÷CBL CBR : .035 to 0.5 (Avg 0.44) Serration Density: DSDI .09 to 1.1 (Avg 1) Distal : 11.5 to 13 / 5 mm Mesial: 10 to 12.5 / 5 mm Other Characteristics Mesial serrations extend to the base on most crowns Transverse Undulations: light present on distal teeth Interdental Sulci: unknown Anterior Dentary Positions Gooves are present on the lingual side of the three anterior teeth Lateral Maxillary Positions (From Morrison Fm) (Data from 11 Teeth Hendrickx study) Crown height ratio CH÷CBL CHR : 1.8 - 2.3 (Avg 2) Crown base ratio CBW÷CBL CBR : .032 to 0.6 (Avg 0.42) Serration Density: DSDI .097 to 1.2 (Avg 1.06) Distal : 9 to 12 / 5 mm Mesial: 9 to 12.8 / 5 mm Oher Characteristics Mesial carina extend to the base on most crowns Transverse Undulations: can be light present Interdental Sulci: can be present If you would like to learn more about Ceratosaurs, bones and teeth there is a great soft covered printing. Ceratosaurs (Dinosauria, Theropoda) A Revised Osteology by Madsen and Welles by the Utah Geological Survey Its also available on PDF but the book is cheap and a great reference guide. If anyone has additional information to add to this please post it. Reconstruction Skull of Ceratosaurus from Utah Museum of Natural History. So you can see variation of the teeth in jaw Reference 1)Journal of Iberian Geology June 2017, Volume 43, Issue 2 , pp 257-291 Analysis of diversity, stratigraphic and geographical distribution of isolated theropod teeth from the Upper Jurassic of the Lusitanian Basin, Portugal 2)Multivariate and Cladistic Analyses of Isolated Teeth Reveal Sympatry of Theropod Dinosaurs in the Late Jurassic of Northern Germany Oliver Gerke, Oliver Wings Published: July 6, 2016 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0158334 3) Taxonomic identification of isolated theropod teeth: The case of the shed tooth crown associated with Aerosteon (Theropoda: Megaraptora) and the dentition of Abelisauridae ChristopheHendrickx, EmanuelTschopp, Martín d.Ezcurra https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0158334
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