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  1. Jurassicbro238

    Lance shark tooth ID help

    A friend of mine found this tooth in Niobrara county, Wyoming while sifting at a microsite. I was thinking Chiloscyllium but I'm not 100% sure and I don't know much about shark tooth ID. Does anyone know what it is? The pinhead is 1.2 mm long for scale.
  2. Hello all, Found some fossils from the Cretaceous period in water. Around Vaals in the Netherlands, Maastrichtian sediments occur. The Kalksteen van Vijlen (Vijlen chalk), Orsbach Kreide (Orsbach chalk) and Kunrader Kalksteen (Kunrader chalk) or Vetschauer Kalksteen are present. Fossils from these sediments consist of belemnites (Belemnella (Pachybelemnella) sumensis (Jeletzky, 1949) and/or Belemnella (Pachybelemnella) cimbrica (Birkelund, 1957), some forms are described as Belemnella ex gr. sumensis/cimbrica and Belemnitella junior (Nowak, 1913), sea urchins (Echinocorys sp. including Echinocorys scutata (Leske, 1778) and Cardiaster granulosus (Goldfuss, 1829), oysters (Pycnodonte vesicularis (Lamarck, 1806), parts of or eroded shark teeth (for example Carcharias sp., Cretalamna lata (Agassiz, 1843), Squalicorax pristodontus (Agassiz, 1843) and Pseudocorax affinis (Münster in Agassiz, 1843). Many fossils are from the Vijlen Chalk (early Early to early Late Maastrichtian). Fossils from the Vijlen 0-3 and Vijlen 4-6 (Vijlen chalk) are approximately between 70.6 and 69.3 million years old (the basis of interval 0 of the Vijlen Member could be dated at 70.6 Ma). Lithology and bioclast contents for intervals 5 (upper part) and 6 of the Vijlen Member at Mamelis (Mamelis 62D-78) have indicated an age of 69.7-69.3 mya. Including the latest part of the late late Maastrichtian (Formatie van Maastricht), the fossils can be between 70.6 and 66 million years old. Internet https://www.somniosus.be/Homepage_set.htm Literature Birkelund, T. (1957). Upper Cretaceous belemnites from Denmark. Det Kongelige Danske Videnskabernes Selskab, Biologiske Skrifter, 9, 1–69, Copenhagen. Christensen, W.K. (1995). Belemnitella from the Upper Campanian and Lower Maastrichtian chalks of Norfolk, England. Special Papers in Palaeontology, 51, 1-84. London. Felder, P.J. & Bless, M.J.M. (1994). The Vijlen Chalk (early Early to early Late Maastrichtian) in its type area around Vijlen and Mamelis (southern Limburg, The Netherlands). Annales de la Société géologique de Belgique 116: 61–85. Felder, W.M. & Bosch, P.W. (2000). Geologie van Nederland, deel 5. Krijt van Zuid-Limburg. NITG TNO, Delft/ Utrecht: 192 pp. Jagt, J.W.M. (2005). Stratigraphic ranges of mosasaurs in Belgium and the Netherlands (Late Cretaceous) and cephalopod-based correlations with North America. Netherlands Journal of Geosciences. 84. 10.1017/S0016774600021065. Jagt, J.W.M. (2012). Belemnitellid coleoids (Mollusca, Cephalopoda) from the type Maastrichtian, the Netherlands and Belgium. Scripta Geologica. Special Issue, 08, 93–112. Jagt, J.W.M, & Jagt-Yazykova, E.A. (2012). Stratigraphy of the type Maastrichtian – a synthesis. Scripta Geologica. Special Issue, 08, 5–32. Keutgen, N., Jagt, J.W., Felder, P., & Jagt-Yazykova, E. (2010). Stratigraphy of the upper Vijlen Member (Gulpen Formation; Maastrichtian) in northeast Belgium, the southeast Netherlands and the Aachen area (Germany), with special reference to belemnitellid cephalopods. Geologie En Mijnbouw, 89, 109-136. Jeletzky, J.A. (1949). Über den taxonomischen Wert einiger morphologischer Elemente des Rostrums der belemnitellenartigen Formen (Familie Belemnitellidae Pavlow, 1913), sowie über die Gattung Belemnella (Nowak, 1913,subg.) Jeletzky, 1941, ihre Phylogenie und einige Vertreter.Neues Jahrbuch für Mineralogie, Geologie und Paläontologie, B9, 257–287. Keutgen, N. (2011). The belemnite zonation of the uppermost Cretaceous in the Maastricht-AachenLiège, Brabant-Méhaigne and Mons areas (Belgium, southeast Netherlands). In: Jagt, J.W.M., Jagt-Jagt. Belemnitellid coleoids from the type Maastrichtian. Scripta Geol., Spec. Issue 8 (2012). Keutgen, N. (2018). A bioclast-based astronomical timescale for the Maastrichtian in the type area (southeast Netherlands, northeast Belgium) and stratigraphic implications: The legacy of P.J. Felder. Netherlands Journal of Geosciences, 97(4), 229-260. doi:10.1017/njg.2018.15 Nestler, H. (2002). Die Fossilien der Rügener Schreibkreide (4. überarbeitete und erweiterte Auflage). Die Neue Brehm-Bücherei Bd. 486., Hohenwarsleben (Westarp Wissenschaften-Verlagsgesellschaft mbH). Schulz, M.G. (1979). Morphometrisch-variationsstatistische Untersuchungen zur Phylogenie der Belemniten-Gattung Belemnella im Untermaastricht NW-Europas. Geologisches Jahrbuch, A47, 3–157. Van der Ham, R. & van Birgelen, M. (1992). Zeeëgels uit het Maastrichtien van de Schneeberg en omgeving (Aken, Duitsland). Natuurhistorisch Maandblad, 81(8/9), 139–153. Description The Cretaceous fossils I found are numerous broken belemnite parts and almost complete ones (species Belemnella (P. sumensis/cimbrica or Belemnitella junior), three belemnite phragmocones, shark teeth (Cretalamna lata, a part of a Squalicorax sp. and other teeth, perhaps one or two Enchodus sp. teeth), one complete Cardiaster granulosus, one part of a oyster (Pycnodonte sp.), small bivalves and one gastropod (possibly Natica cretacea (Goldfuss, 1844) and Holocene or Pleistocene material (not on the photo). I also found a tooth that looks like a reptile or Mosasaur tooth (height around 1 cm). It is cone like and has a thicker root than the shark teeth. One of the fossils is also difficult to determine. It looks like a seed from a tree or other plant. Any ideas? Photo 1: overview of the fossils. Photo 2: some shark teeth, belemnite parts, phragmocones and the very small Mosasaur or reptile (?) tooth. Photo 3: some shark teeth. Photo 4: found the next day a more complete but eroded Squalicorax pristodontus (Agassiz, 1843). All of these teeth are very small, around 0.5-1 cm (only the Squalicorax tooth is a bit bigger).
  3. Fullux

    Dinosaur rib

    I'm interested in this rib end from the Hell Creek formation of South Dakota and was wondering if there was any way to identify the species. I've compared it to several large species that were native to the area and in my opinion, this piece compares very well with tyrannosaurus. Then again I'm no expert and would very much appreciate a second opinion. I've included examples of ribs from each species I compared it to.
  4. About 3 weeks ago I wrapped up my half year of North TX adventures with one final Kamp Ranch hunt and a beautiful pliosaur tooth to boot. Since then I've made my move five hours south to San Antonio and have endured the first two weeks of dental school. It's been an adjustment, but so far things have gone smoothly I'm happy to say. Although I hadn't done any hunting in that time span, I've been putting in some time towards researching sites in this new section of the state. I guess the symptoms of fossil withdrawal were starting to hit hard yesterday, so I picked a few promising spots from my list and headed out to investigate. Some of the decoration in my new apartment There's a lot of formations I want to explore, but my highest priority was locating the Corsicana in order to find some invertebrate rarities like Codiopsis stephensoni or Dakoticancer australis. The bcfas reports made by @Uncle Siphuncle were a big inspiration and also really useful for figuring out what index fossils to look for. I was working with limited information, so the first spot I visited was chosen more or less because it had a promising look to it. I had already made the short-sighted mistake of sleeping in before the expedition, so the Texas sun was out on full blast with the temps exceeding 100F. At the first exposure, I was introduced to hundreds of Exogyra costata littering the ground which was a good sign. This is a species common in the Maastrichtian, but at the time I wasn't sure if it was necessarily indicative of the Corsicana Fm. Interspersed between these massive shells were much smaller bivalves such as the delicate Plicatula mullicaensis. A lot of the invertebrates I was finding were familiar species, but this new flavor of preservation made every discovery very exciting. Eventually, I stumbled upon a huge rudist! I had never found one so complete. Rudist After stowing that and various other bivalves away, I continued creeping along the exposure when I did a double take at a shiny piece of something. Prior to my move, I had come to terms that I may never find marine reptile material here in South TX, yet sitting right in front of me was the glint of enamel... and not just any enamel. As I knelt closer it became clearer and clearer that this was indeed reptilian! I was so happy but also confused as to how such a thing could be possible. I hadn't even snagged my first shark tooth yet and now this! The cutting edge of a mosasaur tooth Labial and mesial views Lingual and distal views Occlusal view As I fished it from the ground I was in awe by its morphology. The tooth has a strong labiolingual compression that had me thinking "dinosaur" for a split second. On the flattened distal carina are very subtle, but visible serrations. The enamel is extremely thin. On the labial side near to the mesial carina, there is a third well-defined carina that reaches a good ways up the tooth. The crown has a very slight labiolingual curvature reserved to the top of the tooth. Around the circumference are some "concave grooves" running longitudinally. I know mosasaurs were extremely diverse in the Maastrichtian, so there are a ton of possibilities. I did a little bit of searching and think it could maybe be Thalassotian atrox? Hopefully an expert or two can chime in here @pachy-pleuro-whatnot-odon @Praefectus @Jared C @PaleoPastels. (Also mosasaur peeps: keep scrolling down for more mosasaur stuff.) Feel free to tag anyone I missed. By now I had finished this outcrop and already downed 1 of my 2 water bottles. There was another larger exposure in the same site that I wanted to visit while my final bottle could last. As I made my way up, I found similar tumbled bivalves as before. Top L to R: Exogyra costata and Plicatula mullicaensis; Bot L to R: Gyrodes sp. and Trigonia castrovillensis? After some closer searching, I found little speckled pebbles that turned out to finally be some irregular echinoids. I guess the other outcrop didn't expose the layer they were coming from. These little guys were just about everywhere and in super good condition. I thought I had collected a ton of species, but looking at them after cleaning I think I only found the two most common. Still super neat to have Maastrichtian age urchins nonetheless. Top: Hemiaster bexari; Bot: Proraster dalli H. bexari with amazing detail Further up, I found the unmistakable texture of crustacean. It was undeniably Dakoticancer australis, but it had definitely seen better days. The elements split the carapace in half, so I tried my best to wrap it carefully. At some point I'll get to gluing it together and cleaning off the extra matrix. Dakoticancer australis carapace Throughout this entire second part of the hunt, I began to wonder more and more about that mosasaur tooth. Was it a fluke? Did some previous hunter drop a Moroccan specimen? I just had never heard of a mosasaur tooth reported from the Corsicana. As I jumped over a gully, a faint shimmer caught my eye and I began to feel deja vu. I squatted down and tried to rediscover whatever it was before I almost fell on my back. There it was, the biggest mosasaur crown I had ever found! HUGE Mosasaur washed out in the gully! Occlusal and basal views Labial and lingual views Distal view I didn't see any detectable serrations but they could be worn off. The cross-section to this robust tooth is circular with many concave grooves running longitudinally. There is a labiolingual curvature. The tip is missing, but I think it is from feeding damage. I would describe the enamel as moderate in thickness. I think it is "faceted", but I am having trouble telling facets and prism faces apart. Honestly, I don't even have a guess for this tooth . I'm not sure of what mosasaurs are even known to occur in the WIS during this time period. I was waiting for my alarm to wake me up at any second. TWO mosasaur teeth and I had yet to even find a shark tooth. Well, that streak came to an end soon after when I spotted a little Squalicorax lindstromi, Carcharias sp., and aff. Cretalamna sp. cusp in quick succession. Squalicorax lindstromi, Carcharias sp., and aff. Cretalamna sp. Finally, my bottle ran dry. I made a quick and early exit, saving the rest of the place for a future hunt. Hopefully the other formations go this smoothly! Thanks for reading
  5. Echinoid Express

    Hardouinia mortonis (Weathered)

    From the album: My Echinoid Collection

    Hardouinia mortonis Peedee Formation Maastrichtian Age, Late Cretaceous (~70 Ma) Holden Beach, Brunswick County, North Carolina, USA Self collected approximately between 2001 and 2005 A forgotten specimen of mine I recently found in a box of old seashells, this is a heavily weathered but mostly complete specimen I found as a young boy. While I've been a fan of fossils for quite some time, I both did not completely know the true nature of these sea urchins around the time, nor did I typically treasure things that had imperfections when I was that young. Now, I can safely say that this is a very special specimen; this may be one of the first fossils, if not the first fossil, I have collected myself. As a sidenote, my younger brother managed to find a nearly perfect specimen sometime between 2007-2010, which was a source of my envy for over a decade until the beach replinishement project!
  6. Mikrogeophagus

    Kemp Clay Pararhincodon?

    I've been sorting through some Kemp Clay (latest Maastrichtian) micros recently, mostly in search of rare sharks. The majority of teeth I've found are easily identified from elasmo's web page on Kemp Clay sharks which itself is based on Case & Cappetta 1997 Kemp Clay paper. However, this singular tooth does not seem to match well with any of those described species or even genera. The closest tooth I could find was Scyliorhinus ivagrantae which is still very different. I think my specimen is Pararhincodon sp., but I cannot find any reputable reports of the genus from the Maastrichtian of Texas (it does show up in the Campanian however). In Germany's Maastrichtian, there is a species called Pararhincodon groessensi which could be it. I did manage to find a senior scholar thesis from an A&M undergrad (Janus 2009) that reported Pararhincodon sp. from the Kemp Clay, so there's a sliver of evidence. Here's the photos: Lateral view Basal Labail Lingual Other views Thanks
  7. Echinoid Express

    Cyclaster pfenderae

    From the album: My Echinoid Collection

    Cyclaster pfenderae Unknown Formation Maastrichtian Age, Late Cretaceous (~70 Ma) Sakaraha, Atsimo-Andrefana Region, Madagascar Acquired from online, July 2023 Rather unusual for Madagascar specimens, this one has very little to no alteration done to it. I am undecided if it has an extremely light polish or not, but it does at least have a little bit of crack repair. This specimen has a very good residual color pattern to it, definitely the best one I've seen to date. I have seen several online that have had a similar degree of coloration.
  8. Echinoid Express

    Gongrochanus herscheliana

    From the album: My Echinoid Collection

    Gongrochanus herscheliana Kallakurichi Formation Maastrichtian Age, Late Cretaceous (~70 Ma) Arialur, Tamil Nadu, India Acquired from online, July 2023 A fairly uncommon echinoid (and location), it's similarities to Hardouinia piqued my interest in the genus. The test has a rather unusual shape, it vaguely resembles the shape of a hard hat when viewed from the side.
  9. Mikrogeophagus

    Palaeogaleus navarroensis

    From the album: Kemp Clay

    Palaeogaleus navarroensis, North TX Maastrichtian, Cretaceous Jun, 2023
  10. Mikrogeophagus

    Squatina hassei

    From the album: Kemp Clay

    Squatina hassei, North TX Maastrichtian, Cretaceous Jun, 2023
  11. Mikrogeophagus

    Lonchidion babulskii

    From the album: Kemp Clay

    Lonchidion babulskii, North TX Maastrichtian, Cretaceous Jun, 2023
  12. Mikrogeophagus

    Ptychotrygon vermiculata

    From the album: Kemp Clay

    Ptychotrygon vermiculata, North TX Maastrichtian, Cretaceous Jun, 2023
  13. Mikrogeophagus

    Ptychotrygon winni

    From the album: Kemp Clay

    Ptychotrygon winni, North TX Maastrichtian, Cretaceous Jun, 2023
  14. Mikrogeophagus

    Ischyrhiza mira

    From the album: Kemp Clay

    Ischyrhiza mira, North TX Maastrichtian, Cretaceous Jun, 2023
  15. Mikrogeophagus

    Sclerorhynchus pettersi

    From the album: Kemp Clay

    Sclerorhynchus pettersi, North TX Maastrichtian, Cretaceous Jun, 2023
  16. Mikrogeophagus

    Ischyrhiza avonicola

    From the album: Kemp Clay

    Ischyrhiza avonicola, North TX Maastrichtian, Cretaceous Jun, 2023
  17. Mikrogeophagus

    Hadrodus

    From the album: Kemp Clay

    Hadrodus, North TX Maastrichtian, Cretaceous Jun, 2023
  18. ThePhysicist

    Baby Leptoceratops

    From the album: Hell Creek / Lance Formations

    Triceratops's smaller cousin, this Ceratopsian lacked horns. Note the single root. This is a very small tooth, likely from a baby (the root being present also means that unfortunately this dinosaur did not survive into adulthood).
  19. ThePhysicist

    Metatherian

    From the album: Hell Creek / Lance Formations

    A mammal tooth from the group that includes the marsupials. Found in a channel deposit, it's remarkable that the roots are still intact.
  20. ThePhysicist

    Pectinodon tooth

    From the album: Hell Creek / Lance Formations

    Pectinodon (meaning "comb-tooth") is a tooth taxon, since no remains attributable to the genus beyond teeth have been found. Pectinodon seems to be a rare member of the Hell Creek fauna, with their teeth being fairly uncommon (though being so small, I'd guess that few people actively search for them). It was a small Troodontid theropod, with teeth that couldn't handle stresses as well as their Dromaeosaurid and Tyrannosaurid cousins (Torices et al. (2018)). This coupled with their small size suggest that Pectinodon was a small/soft prey specialist, preferring the rodent-sized mammals of the time, lizards, insects, etc. Some researchers have proposed omnivory as a possibility for Troodontids (cf. Holtz et al. (1998)). Troodontids famously are regarded as among the most intelligent dinosaurs for their large brain size / body size ratio. This notion serves as fodder for speculation that had the dinosaurs not gone extinct, Troodontids (Pectinodon being (one of?) the last) would have continued to grow in intelligence and develop sentience and civilizations. Troodontid teeth like Pectinodon can be easily identified by their small size, exaggerated, triangular, apically oriented posterior serrations.
  21. ThePhysicist

    Dromaeosaurid

    From the album: Hell Creek / Lance Formations

    A small tooth from a Dromaeosaurid "raptor" dinosaur, located in an anterior position in the mouth. Found in a channel deposit.
  22. Hello all! I've been getting ready for the Aurora Fossil Festival (and working on my new display cabinet), and have been going back through my Holden Beach finds. I wanted to share a compilation of my visits to Holden Beach, North Carolina from 2022 to 2023. I have gone 5 times since the replenishment project occurred there: April 2022, twice in October 2022, February 2023, and April 2023. While I was mostly picking up the Hardouinia mortonis echinoids, I found a little bit of everything out there. There was so much that I couldn't include everything, so I stuck with the best of my finds. It's truly amazing what all can be found washing out down there! I am still fairly new to fossils in general, and I'm far from confident in my ability to I.D. a lot of things. That being said, I have tried my best to identify what I could. Any corrections or advice is more than appreciated! I can also take additional pictures if anyone wants a better look at anything here. Here are all my sharks teeth. I am not great with the I.D.s on all of these, but I do know the names to a few varieties. I have tried to group them together by what little I know, and by appearance if I'm unsure. Lots of great white and crow shark teeth were to be found. April 2022, October 2022 and February 2023: This one in particular is my favorite shark find of 2022. It's the largest Great White tooth I've found, and aside from a small chip off of the side and the tip it's in really good shape. It's right at 6 cm (2.36 Inches) long, but I have no doubt it would have been longer with the tip undamaged. (April 2022) April 2023: A modern Sand Tiger tooth snuck in as well. Now for my absolute favorite tooth, my only mostly intact Megalodon tooth that I've found to date. This one is right at 9.52 cm (3.75 Inches) long in it's current condition. (April 2023) On to my Hardouinia mortonis, this is a group photo of my best finds from all trips. The Holden Beach ones get fairly large compared to some of the quarry finds I've seen! I have several well over 5 cm (~2 Inches) in diameter. These are specimens with minor pathologies. The apical disc sometimes is "dented" on these specimens, and I've found a few with "peanut" shaped petals. (Various trips) This is a specimen with a more moderate pathology. the whole shape is unusual, and one petal is turned at about a 20-30 degree angle towards the posterior. (February 2022) These are some of my current "project" echinoids. Due to being found on the beach, they tend to be saturated with salt. while I try to manually remove some matrix periodically I give them a good soak in water for a few days, then leave them out to dry and see if salt crystals are still forming. Sometimes it takes a few tries to completely rid the salt. This batch has some Hardouinia mortonis of some pretty varied shape. (Various trips) These are mostly Mosasaur teeth, though there may be a few crocodilian teeth snuck in there as well. I'm not exactly sure which species of mosasaur these are, there are some distinctly different shapes to some of them. (Various trips) I found plenty of Mosasaur teeth without roots, but only one root without a tooth! The kind folks at Aurora helped me identify this, I wasn't sure what it was. (April 2022) I never got this one identified, but it's definitely a piece of some jaw with a tooth root. Perhaps also Mosasaur, but I'm not sure. (April 2022) Of course there was also plenty of Exogyra to go around, and way too many to photograph! This is a small cluster of them in the matrix, and the largest intact specimen I found, at around 10 cm (~4 Inches) long. (Cluster from April 2022, large one from October 2022) (*EDIT 6-18-23 with proper I.D.) These are Cretaceous Prehepatus harrisi crab claws. All but one came from the April 2022 trip (the darker is from February 2023). These are Pleistocene Equus teeth I found in April 2022. There was a much smaller fourth fragment as well I didn't photograph. This is one of my favorite finds: a Pleistocene Odocoileus antler fragment. It resembles a modern White-Tailed Deer antler fragment! (April 2022) A very large bone fragment from April 2022. Not sure what from, almost looks like a vertebra. Around 9 cm (3.54 Inches) long. A Rhombodus binkhorsti tooth, my only one found. (April 2022) Other Ray teeth and barbs (Various trips) My first and only Pycnodont mouth plate fragment (April 2023). Some sizable shark vertebrae. (Various trips) Some Sawfish rostral teeth and a few select Enchodus fangs / jaw fragments. (Various trips) Some Sea Robin skull plates. (Various trips) Some turtle carapace fragments, and possibly a Crocodilia Dermal Scute (Various trips for the turtle fragments, April 2023 on the scute) This is an interesting bone fragment that, according to the folks at Aurora, might have signs of a shark attack or feeding due to the triangular groove on it. (April 2022) Plenty of steinkerns to pick up! (Various trips) While I found a few isolated casts of ammonite chambers, this is by far the largest and best one. I'm not exactly sure what species, but after reading my NCFC book I'm leaning towards Sphenodiscus lobatus. (October 2022) Unknown vertebra, pretty heavily worn. About 4 cm (1.57 Inches) long. (April 2023) My Sirenia vertebra. (Thank you @Boesse for helping me confirm this!) (April 2023) The folks at Aurora have said this is likely a young Mastodon molar fragment. I've seen even smaller fragments with a similar shine and color that might also be some kind of Proboscidea tooth fragment. (April 2022) A fragment of some unknown echinoid. It doesn't resemble Hardouinia to me, it almost looks more like a fragment from something in the Spatangoida Order. I'm not 100% sure on it though. I wish there was more of it to look at! (April 2023) And last but not least, a couple of Sirenian rib fragments. (April 2022) Bonus pic: These are my favorite Hardouinia mortonis specimens. I had someone at work etch me out the plaque on a laser.
  23. Edited (04/14/23) With all of the new discoveries over the past few years there is very little out there that is current or accurate. Here is my view of the Dinosaurian/Crocodilian fauna from the Hell Creek and Lance Formation excluding Avialae. Let me add that the lack of a large dataset or complete specimens leaves many unanswered questions for many of these genera. New discoveries will be needed to firm up a any listing of the fanual listing Tyrannosauridae: - Tyrannosaurus rex (Osborn 1905) - Nanotyrannus lancensis (Bakker et al. 1988) - Aublysodon mirandus (Not Valid) Alverezauridae: - Trierarhunchus prairiensis (Fowler et al. 2020) Ornithomimidae: - Struthiomimus sedens? (Marsh 1982) - Ornithomimus velox (March 1890) Caenagnathids: - Anzu wyliei (Lamanna et al. 2014) - Caenagathid indet. including Leptorhynchos (Discussion with P. Larsen multiple additional species probably exist and fragmentary material is known) Dromaeosauridae: - Acheroraptor temertyorum (Evans et al. 2013) - Dakotaraptor steini (DePalma et al. 2015) - Dromaeosaurid indet. (Discussion with P. Larsen and the fact that numerous isolated teeth & foot claws exist which do not fit the other two taxons) - Microraptoria indet. ? (Based on isolated bones in my collection ID as possible by prominent paleontologist, also known from North American Campanian deposits) Troodontidae: - Pectinodon bakkeri (Carpenter 1982) - cf Troodon formosus - cf Zapsalis abradens (not valid) Other Theropods: - cf Richardoestesia gilmorei - cf Richardoestesia isosceles - cf Paronychodon lacustri Ankylosauria: - Ankylosaurus magniventris (Brown 1908) - Denversaurus schlessman (Bakker 1988) - cf Gilyptodontopelta (Nodosaur)(Partial skeleton exists and in the process of being studied by a major museum) (have an isolated osteoderm in my collection, its very distinctive) Pachycephalosauria: - Pachycephalosaurus wyomingensis (Gilmore 1931) - Sphaerotholus buchholtzae (Williamson et al. 2002) - Platytholus clemensi (Horner et al. 2023) Ceratopsidae: - Leptoceratops gracilis (Brown 1914) - Leptoceratops sp. (BHI fragmantry material) - Tatankaceratops sacrisonorum (Ott & Larsen 2010) - Torosaurus latus (Marsh 1891) - Triceratops horridus (Marsh 1889) - Triceratops prorsus (Marsh 1890) Others more problematic: - Triceratops sp 2 (Fowler 2017) (MOR 3027 Yoshi specimen) - ?Chasmosaurine MOR 1122 7-22-00-1 - ?Ceratopsian indet. (skulls floating around that are claimed to be a new species including: Nedoceratops hatcher, Lance Fm and Duranteceratops, Hell Creek Fm) Hadrosauridae: - Edmontosaurus annectens (Lambe 1917) - ?Lambeosaurine (Based on a large humerus) Thescelosauridae: - Thescelosaurus neglectus (Glmore 1913) - ?Thescelosaurus gabanii (Morris 1976) (Based on fragmentary material) (A poster was presented at the SVP 2022 meeting of two T. neglectus skulls identified as Male and Female...T gabanii?) Crocodylia: - Borealosuchus sternbergii (Brochu 1997) - Brachychampsa montana (Gimore 1911) - Thoracosaurus neocesariensis (de Kay 1842) - ? Prodiplocynodon langi (Mook 1941)
  24. Mikrogeophagus

    Rhombodus binkhorsti

    From the album: Kemp Clay

    Rhombodus binkhorsti, North TX Maastrichtian, Cretaceous Jun, 2023
  25. Mikrogeophagus

    Brachyrhizodus wichitaensis

    From the album: Kemp Clay

    Brachyrhizodus wichitaensis, North TX Maastrichtian, Cretaceous Jun, 2023 Not described in Case and Capetta's study of the Kemp Clay, so this specimen may have washed from another formation despite being surrounded by Kemp Clay.
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