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  1. Jared C

    Ptychodus occidentalis

    From the album: Texas Cenomanian (Cretaceous)

    Ptychodus occidentalis Uppermost middle Cenomanian Texas My most spectacular Ptychodus tooth, which I almost didn't find. I was finishing the day, and then decided to remove one last slab of sandstone before moving on. It is a decently sized tooth for the species, at 22 mm (0.87 inches) tall and 19 mm (0.75 inches) wide.
  2. Untitled

    Kem Kem Leptostyrax macrorhiza

    From the album: Cretaceous Shark Teeth

    A very rare Leptostyrax from the Kem Kem beds of Morocco. Lower Upper-Cenomanian in age.
  3. Winter is the best time of the year for fossil hunting near the cliffs at the french coast. So like every year Natalie and I spend a few days at the "Côte d'opale" in northern France to prospect. The storms and tides cleaned up a lot of the boulders from the last cliff fals. The weather conditions were a bit harsh but we managed a few good prospections and we scored a few large ammonites.
  4. The below open access paper is interesting. Tykoski, R.S., Contreras, D.L. and Noto, C., 2023. The first small-bodied ornithopod dinosaur from the Lewisville Formation (middle Cenomanian) of Texas. Journal of Vertebrate Paleontology, p.e2257238. Yours, Paul H.
  5. A new genus of bill-fish like Plethodid Rhamphoichthys has been described from the Cretaceous of Lebanon and Germany. paper link: https://www.researchgate.net/publication/376263633_The_first_articulated_skeletons_of_enigmatic_Late_Cretaceous_billfish-like_actinopterygians What's interesting is that the billfish like body plan here is AGAIN convergent - Rhamphoichthys is a Plethodid, unrelated to the more famous Creteaceous "billfish" Protosphyraena (a Pachycormid). Both of these are yet again unrelated to modern billfish (the Xiphiidae). In this paper, two previously dubious species of Protosphyraena have been assigned to this new genus: P. stebbingi and P. minor, now R. stebbingi and R. minor. Pics!
  6. Jared C

    Plethodid parasphenoid with teeth

    From the album: Texas Cenomanian (Cretaceous)

    Plethodid parasphenoid with teeth intact Cenomanian Texas Plethodid parasphenoids are usually found without the little teeth in place, each tooth only leaving a small pit behind instead.
  7. Jared C

    Plethodid parasphenoid frags

    From the album: Texas Cenomanian (Cretaceous)

    Plethodid parasphenoid fragments Cenomanian Texas These bones were at the roof of the mouth towards the back, with each pit originally housing a tiny tooth
  8. Cifuentes-Ruiz, P., 2023. First biological inclusion in Upper Cretaceous Texas amber, USA. Boletín de la Sociedad Geológica Mexicana, 75(3), no.A091023. Boletín de la Sociedad Geológica Mexicana Yours, Paul H.
  9. Wrangellian

    Lebanon shrimp - Carpopenaeus?

    I seem to have lost my label for this one, but if I recall it was a Carpopenaeus (callirostris?) from Haqel, Lebanon - Cenomanian. Can anyone confirm this for me? I'm pretty sure it was from Lebanon, in any case. If any other info can be filled in also, let me know, please. Maybe my label will turn up somewhere, sometime... I know I would not have thrown such a thing out.
  10. Plant impressions i found in material from the Coleraine formation of Northern Minnesota, which dates to 100-90mya, i confirmed with a paleontologist that these are first known plant impressions ever found up here which has me excited but neither of us know anymore than that theyre plant impressions, can anyone here maybe give more specific information from my pictures? i hope these pictures are good enough, i donated it for further study so I can’t get more. Even if you can’t ID them i still want to know what you guys think!
  11. Fullux

    Hadrosaur?

    Howdy all, This is supposedly a hadrosaur tooth from the Woodbine formation of Dallas Texas that I'm very interested in. (If you know you know) Do y'all think the ID is accurate?
  12. Mikrogeophagus

    Leptocleidian Plesiosaur, Rush Creek

    From the album: Woodbine Formation

    Leptocleidian Plesiosaur, North TX Cenomanian, Cretaceous Jul, 2023 Between Leptocleididae and Polycotylidae it is unclear which of the two sister families (both within the clade Leptocleidia) this tooth belongs to. This tooth is from marine coastal strata that would have been in near proximity to freshwater sources (see the Woodbine river delta that once existed over Grapevine Lake). Leptocleididae is known up until the Early Albian from freshwater, near shore, and brackish environments. Some possible teeth were documented from the Kem Kem river system which is similarly aged Cenomanian rock. They typically have very gracile teeth similar to this specimen. Polycotylidae is a sister taxon that extends through into much younger deposits and is regarded as a marine group. They arose in the Albian and typically have more robust morphologies, though a basal species could be gracile like this specimen.
  13. Last weekend Natalie and I found an isolated bone in the chalk of Cap-Blanc-Nez in France. Bone fragments here are very rare, and most of the time they are from the Ichthyosaur Pervushovisaurus campylodon. So we think this might be some part of that creature altough a small one. Is there anyone who can narrow it down to a specific bone? The bone is around 3,5cm long. The age: late cretaceous, Early Cenomanian.
  14. Irongiant97

    Cretaceous Reptile Tooth

    I found this in material from the Coleraine formation of Northern Minnesota, which dates between 100-90mya, which was part of the east shore of the Western Interior Seaway. So far i know it’s reptilian but I’m wondering if anyone can give me a more specific identification. The exposed part is about 2.5-3cm long.
  15. Hey everyone! Towards the end of my time down in Austin, I collected a dozen or so bags of matrix across three sites that covered the Bouldin Flags (Cenomanian), South Bosque (Turonian), and basal Atco (Coniacian) of Central Texas. Over the course of the last 6 months, I have processed and tried to identify everything that my sieve caught in order to complete this project of mine. I’m sure there are plenty of errors within this amateur study, but I hope that the overall information it provides will at least be of some use to my fellow hunters who are looking for a centralized place to figure out just what kind of tooth they stumbled upon in their local creek. I know that, especially in my first year of fossil hunting, the seemingly endless list of shark names looked like a mountain too tall to overcome. Perhaps this report might just help to demystify that obstacle. There were many expected finds and some total surprises. I learned a lot myself from this whole endeavor and am excited to share what I found. Special shoutout to @Jackito and @LSCHNELLE for so kindfully sharing their fantastic sites as well as their expertise. This could not have been done without their help! Also, if you have found a species of shark not mentioned in this report from the Bouldin Flags, South Bosque, or Atco of Central Texas, feel free to leave a reply with a photo and some info on your specimen! Enjoy! Abundant (), Common (), Uncommon (), Rare () Bouldin Flags (Cenomanian) The Bouldin Flags represents the end of the Cenomanian stage of the WIS in Central Texas. It carries much of the typical “Woodbinian fauna” that is often associated with Cenomanian sites from across the continent. The formation is “flaggy”, tending to split into layers. Much of the formation can be devoid of vertebrate life, but now and then, extremely rich layers may crop up and yield an extensive diversity of sharks, bony fish, and even reptiles to collect from. Processing the matrix can be difficult. I tried to process only the softest material I could find from productive layers as the harder parts were sometimes almost solid pyrite or totally cemented into an unbreakable stone. Even the parts that are soft tend to carry lots of grit that are rough on the hands and fossils. Nevertheless, the Bouldin Flags has some of the most diverse shark and reptile fauna as well as the richest layers, making it well worth the effort of locating. The majority of the collecting for this formation was done in the Lower Bouldin Flags, however, specimens that also occurred in the limited Upper Bouldin Flags sampling will be marked with an asterisk (*=Upper BF) Lamniformes *Carcharias saskatchewanensis Together with Cenocarcharias tenuiplicatus, these species make up the two most abundant sharks teeth to be found in the Bouldin Flags. They are typically only millimeters in size and tend to separate well from the matrix without breaking. C. saskatchewanensis can be easily differentiated from C. tenuiplicatus by its absence of fine striations on the labial faces of the cusps and cusplets. C. saskatchewanensis and C. tenuiplicatus are distinguished from Haimirichia amonensis by their significantly smaller size. I have also seen this species referred to as Microcarcharias saskatchewanensis. *Cenocarcharias tenuiplicatus A common tiny tooth found in the Bouldin Flags. They are easily identified by the presence of fine striations on the labial faces of their cusps/cusplets. Now and then, they may have an extra pair of cusplets. Cretalamna catoxodon Surprisingly rare given how abundant this genus usually is in other similarly aged strata of Texas. From the entirety of my material, I only came across one identifiable specimen in the final batch. Unlike mature Cretoxyrhina agassizensis, these teeth have a single pair of pointed cusplets and are usually more gracile. Unlike Cretodus semiplicatus, these teeth are more gracile and lack wrinkling on the base of the crown and cusplets. C. catoxodon is a relatively newly defined species within the genus Cretalamna and, to my knowledge, the only one documented from the Cenomanian. Cretodus semiplicatus One of the most coveted shark fossils of the Eagle Ford is the fearsome Cretodus. These are some of the biggest and most robust teeth to be found and can be spotted quickly by their size and diagnostic wrinkled crown bases on both the labial and lingual faces. To my knowledge, C. crassidens does not appear until the Turonian. C. semiplicatus, unlike Cretodus houghtonorum, typically exhibits a U-shaped basal concavity and U-shaped crown base border whereas C. houghtonorum is more of a V-shape in both departments. Both typically have gracile cusps. In my hunting at the Bouldin Flags site, I found one perfect tooth and a single, large broken off cusp to another tooth. Cretomanta canadensis This is one of the most interesting teeth to be had in the Bouldin Flags. Cretomanta has been interpreted as a planktivorous filter feeder. These teeth are sometimes confused with rostral denticles of Ptychotrygon triangularis, however the oral teeth of P. triangularis were not found at all in the Bouldin Flags Site. In contrast, the Atco Site (more on this later) did produce many of these oral teeth. I believe this suggests P. triangularis is likely not the culprit for the pictured specimens. Additionally, Cretomanta canadensis is commonly listed in faunas of other Cenomanian sites. Fairly recently in Northern Mexico, an amazingly preserved ray-like filter-feeding shark was discovered and named Aquilolamna milarcae. Sadly, no teeth were preserved, making it impossible to confirm synonymy between Aquilolamna and Cretomanta, but nevertheless there is a suspected connection between the two which future discoveries may one day prove. *Cretoxyrhina agassizensis On the right are the juvenile C. agassizensis ("Telodontaspis agassizensis") Cretoxyrhina are always a welcome sight and not all that rare for the Bouldin Flags. These are some of the larger teeth to be had and are generally well preserved. They typically do not have cusplets, however some specimens may have poorly developed ones as Cenomanian Cretoxyrhina were still in the process of diminishing them. C. agassizensis is a chronospecies of the genus Cretoxyrhina, representing the time period of the Late Middle Cenomanian to the Early Middle Turonian. Throughout the sifting process, I came across small, thinly cusped and distally curved teeth that somewhat resembled the larger Cretoxyrhina teeth I had as well. In researching possible IDs for these teeth, I came across the species Telodontaspis agassizensis which seemed like a decent match. However, Siversson makes the point that this taxon seems to appear only in places where larger, more typical Cretoxyrhina specimens also occur. It would seem that the two genera are synonymous and these smaller teeth instead belong to juvenile C. agassizensis. *Haimirichia amonensis Medium-sized teeth that are extremely abundant in the Bouldin Flags as well as many other Cenomanian deposits of Texas. A decent degree of heterodonty exists and lateral teeth may have many pairs of cusplets. This species was previously known as Carcharias amonensis, however the discovery of a new and well preserved specimen showed that it possessed enough morphological differences to warrant the creation of the family Haimirichiidae. I originally misidentified these teeth as Scapanorhynchus raphiodon which appears to not exist in the Bouldin Flags. *Squalicorax sp. Squalicorax is one of the most abundant teeth present. They are easily identified by their unique shape that highlights their generalist diet. There is currently much work to be done in properly separating the species of this genus across the Mesozoic, so I will simply refer to all teeth found as Squalicorax sp. Ptychodontiformes *Ptychodus anonymous The most common Ptychodus teeth found in both the Bouldin Flags and South Bosque. P. anonymous can be distinguished from other co-occurring Ptychodus teeth most easily on the basis of having a defined marginal area where the transverse ridges will merge instead of bifurcating and running all the way to the end of the crown. P. anonymous is known to have two distinct morphotypes (Cenomanian vs. Turonian), both of which are represented in this post. The Cenomanian morphotype is common in the Bouldin Flags and are typically smaller and more robust than their Turonian counterparts (however my Turonian specimens are just as small as my Cenomanian ones). Another key difference in the morphotypes is that Turonian teeth have an apparent concentric ornamentation of the marginal area whereas Cenomanian teeth have no such feature. It is possible, in the future, these differences may lead to the creation of a new species between the morphotypes. *Ptychodus decurrens This larger specimen in the lower 3 photos was misidentified. I now believe it to be a P. decurrens from the Upper Bouldin Flags. Ptychodus decurrens is a low crowned tooth that is also numerous in this formation. Like Ptychodus occidentalis, the transverse ridging gradually bifurcates to the edges of the crown as opposed to terminating at a distinct marginal area. These teeth are often broad and have the ability to get quite large in size. The bottom specimen shown was originally misidentified as P. marginalis. I have taken another look and now realize P. decurrens is a stronger ID. Despite it being a fragment, I do not think the tooth shows signs of a concentric orientation of transverse ridges and instead seems to follow the hooked on one side and straight on the other ridge pattern more typical of larger P. decurrens. Also, I initially misidentified the formation the tooth came from as being South Bosque based on visuals alone. After getting the chance to process the matrix for micros, it shares much of the same microfauna with the Lower Bouldin Flags and has little faunal overlap with the South Bosque outcrop. I now believe the location to be Upper Bouldin Flags. Ptychodus occidentalis Ptychodus occidentalis is rarer in the Bouldin Flags than the other Ptychodus. They can be identified by the bifurcating nature of their ridges as they travel through the marginal area of the tooth to the edge of the crown. The crown height tends to be higher than that of Ptychodus decurrens. In comparison to P. anonymous, P. occidentalis generally possesses finer and more numerous transverse ridges. This species is also capable of producing some very large teeth. Ptychodus rhombodus is a smaller-toothed species that commonly occurs in the Cenomanian WIS that also shares bifurcating ridge features. It has been suggested, however, that these may represent a juvenile form of P. occidentalis. Orectolobiformes *Cantioscyllium decipiens Common little teeth that belonged to a Mesozoic nurse shark. The teeth look similar to Chiloscyllium, but have striations present on the labial face. Sclerorhynchiformes *Onchopristis dunklei Although not the rarest to find, Onchopristis dunklei represents an order of sharks that hardly seems to be found in the Bouldin Flags. This species tends to preserve both oral teeth and rostral teeth. The rostral teeth are quite iconic, being best known for the multiple barbs decorating its edge. These teeth are fragile and rarely collected in one piece. From the Lower Bouldin Flags, I collected a handful of oral teeth and broken rostral specimens. In my small sample of Upper Bouldin Flags material, I only collected one O. Dunklei rostral and it happened to be the single complete one in the collection. Hybodontiformes Indet. Hybodontiformes Only a singular specimen of a Hybodontiformes tooth fragment was recovered. I don’t believe enough is present to make a confident determination as to whether it belongs to Meristodonoides or some other genera. It has striations on both sides of the tooth and a slight curvature. Other Fauna Amiid? A single, tiny arrow shaped fish tooth was collected. It is difficult to confidently lay down an identification, but Amiid is a candidate for this morphology. Coniasaurus crassidens Coniasaurus crassidens may be found in the Bouldin Flags on rare occasion. Most commonly, teeth, jaw fragments, and vertebrae are found disarticulated amongst shark teeth and shells. Because of their position within the order Squamata, Coniasaurus vertebrae share many visual similarities with larger mosasaur vertebrae from younger strata such as the Ozan. Although Coniasaurus teeth exhibit heterodonty, most of their teeth have a characteristically bulbous shape that distinguishes them from all co-occurring sharks and fish (though anterior-most maxillary teeth may be quite gracile in contrast). While Coniasaurus seems to be restricted to the Cenomanian in England, American specimens cross the Cenomanian-Turonian oceanic anoxic event (OAE 2) and reach the Middle Turonian with some reports even further beyond. Enchodus sp. Typical of just about every Cretaceous exposure in Texas is the saber-toothed Enchodus. The Bouldin Flags is absolutely filled with them. The teeth are generally quite small and vary in shape. Most commonly, they are flattened and take on a recurved shape. Sometimes they may be conical and completely straight. They may be smooth or have striations. Pachyrhizodus minimus These are very small and resemble miniature mosasaur teeth. They are smooth around their circumference and have a strong distal curvature. Pachyrhizodus is a genus known for having relatively large heads, similar to modern Grouper fish. Protosphyraena sp. Protosphyraena was a genus of fish that heavily resembled modern swordfish. Their teeth are common finds all over Texas. They generally take on a flattened shape and bear two cutting edges. They can sometimes have a slight curvature or stay completely straight. The ones I collected were among the larger fish teeth found. Known but missing sharks Pseudomegachasma comanchensis Despite not having personally collected one, Pseudomegachasma comanchensis is known from the Bouldin Flags. Similar to Cretomanta, these sharks are suspected to have been the oldest elasmobranch planktivorous filter feeders. The lingual protuberances on these teeth are so large, they almost look like backwards root lobes. Ptychodus marginalis Ptychodus marginalis is better known from the South Bosque, but has been previously found in the Bouldin Flags, though it is on the rarer end as far as Ptychodus go. They can get large, sometimes to the size of a golf ball. P. marginalis is distinct from other Texan species of the genera in that its ridges go on to form concentric rings as they travel towards the edges of the crown.
  16. The cenomanian sediments of Lebanon contains three Cyclobatis-species. The long-tailed C. major, the rare C. tuberculatus and the more common C. oligodactylus. One more might be possible, there is a stingray known with a very short spine, shorter than the others
  17. LordTrilobite

    Kem Kem Vertebrae ID Thread

    So, lets figure out vertebrae from the Kem Kem beds. As many of you know the Kem Kem beds has a pretty enigmatic palaeo fauna. There is some literature about it, but not a whole lot. Some of it is behind a paywall and much information is pretty scattered. So I got this idea that maybe we could combine our knowledge and information to collectively get a better picture of which bone belongs to which animal, in this case, vertebrae. I know some of you have some fantastic specimens in your collections, if we combine these in this thread we might be able to see some patterns. We probably won't be able to put a genus or species name on each type, but perhaps assigning certain vertebrae to a morphotype might be possible. With that I encourage everyone that has any vertebrae from the Kem Kem beds to share photos of their specimens and post them here so we can use this thread as a sort of library as well as an ID thread that everyone can use to better ID their Kem Kem vertebrae. So please, share your photos! And it might help to number your specimens for easier reference. I will be updating this first post as new information arises with examples to make ID easier. Theropods Spinosaurids Spinosaurus aegyptiacus Spinosaurus is known for it's tall neural spines, which are pretty characteristic. Unlike Sigilmassasaurus, Spinosaurus does not have the ventral triangular rough plateau on the centra Spinosaurus mid cervical vertebra Spinosaurus dorsal, sacral and caudal vertebrae Caudal vertebrae Nearly complete tail from the neotype specimen of Spinosaurus aegyptiacus Sigilmassasaurus brevicollis Sigilmassasaurus is a Spinosaurid that might be closely related to Baryonyx and Suchomimus. It differs from Spinosaurus in that it has a ventral keel on many vertebrae and a triangular rough plateau on the bottom back end. A is Sigilmassasaurus, B is Baryonyx Sigilmassasaurus cervical vertebrae From anterior to posterior Sigilmassasaurus dorsal vertebrae Indeterminate Spinosaurid vertebrae Not a whole lot has been published yet, some bones can probably not be ID'd on genus level. Spinosaurid caudal vertebrae Anterior caudal: From LordTrilobite's collection Mid-posterior caudal: From Paleoworld-101's collection Mid-posterior caudal: From LordTrilobite's collection This caudal vertebra is less tall and more pinched in the middle of the centrum than the one from Paleoworld-101's collection. Likely due to a slightly more posterior position. Mid-posterior caudal: From LordTrilobite's collection Carcharodontosaurids Due to an old paper Sigilmassasaurus vertebrae are sometimes misidentified as Carcharodontosaurid. These vertebrae should be identified on the basis of the original description by Stromer. Two species of Carcharodontosaurids are known from the Kem Kem beds at this time. Carcharodontosaurus saharicus and Sauroniops pachytholus. Carcharodontosaurid cervical vertebrae Deltadromeus agilis Anterior (left) and mid (right) caudals better examples needed Abelisauroids Indeterminate Abelisauroid distal caudal From LordTrilobite's collection Abelisaurid dorsal vertebrae From Troodon's collection Sauropods Rebbachisaurus garasbae Not a whole lot is known about this titanosaur, as only a few bones have been found. Notice that the vertebrae are very extensively pneumaticised. Rebbachisaurus dorsal vertebrae Sauropod mid caudal vertebra. Possibly Rebbachisaurid. Unnamed Titanosaurian mid caudal vertebra Crocodilomorphs more examples needed Kemkemia This crocodile is only known by a single posterior caudal vertebra. Kemkemia caudal vertebra Turtles examples needed Pterosaurs Azhdarchids Azhdarchid (probably Alanqa) posterior fragment cervical vertebra Azhdarchid Mid cervical vertebra Sources Spinosaurids https://peerj.com/articles/1323/?utm_source=TrendMD&utm_campaign=PeerJ_TrendMD_1&utm_medium=TrendMD http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0144695 Sauropods Jeffrey A. Wilson & Ronan Allain (2015) Osteology of Rebbachisaurus garasbae Lavocat, 1954, a diplodocoid (Dinosauria, Sauropoda) from the early Late Cretaceous–aged Kem Kem beds of southeastern Morocco, Journal of Vertebrate Paleontology, 35:4, e1000701, DOI: 10.1080/02724634.2014.1000701 https://www.researchgate.net/publication/304214496_Evidence_of_a_derived_titanosaurian_Dinosauria_Sauropoda_in_the_Kem_Kem_beds_of_Morocco_with_comments_on_sauropod_paleoecology_in_the_Cretaceous_of_Africa Kemkemia sisn.pagepress.org/index.php/nhs/article/viewFile/nhs.2012.119/32 Pterosaurs https://docs.google.com/viewer?url=http%3A%2F%2Fwww.thefossilforum.com%2Fapplications%2Fcore%2Finterface%2Ffile%2Fattachment.php%3Fid%3D432009&fname=journal.pone.0010875.PDF&pdf=true https://riviste.unimi.it/index.php/RIPS/article/view/5967
  18. pachy-pleuro-whatnot-odon

    British Wealden aigialosaur

    Hi all, I was recently told about supposed Aigialosaurus/aigialosaurid (mosasaurus) material from the Wealden at Bexhill-on-Sea in East Sussex, and was wondering whether anybody knows anything more about this. Because, as far as I'm aware (Wikipedia), Aigialosaurus is described from Hvar in Croatia and, moreover, temporarily restricted to the Cenomanian, whereas these remains, stemming from the Wealden, would be Early Cretaceous in age (Berriasian through Aptian) - most likely Valanginian, as they were recovered from Bexhill-on-Sea. (Image source) I must say these remains do look rather mosasauroid, although I've been unsuccessful in finding further information on the specimen, which is supposed to be housed in the Bexhill Museum. The person who first told me about them remembers having seen a newspaper article, believes the British Natural History Museum was involved with the specimen back then, and had heard about a paper being written about it. That's about all I have to go on for now. So my questions right now are: does anyone have more information on this specimen; know of the publication; and what do people here generally make of this piece: is it mosasauroid, or could it be something else? @paulgdls @DE&i @Praefectus @caterpillar @The Amateur Paleontologist @Kosmoceras @ThePhysicist @Welsh Wizard @DanJeavs
  19. The Amateur Paleontologist

    Fairly recent bit of opal fossil research

    After learning about Weewarrasaurus, I thought it'd be nice to report the 'lesser-known' recent bit of research about the opalised fossil site Lightning Ridge (New South Wales, Australia) It's basically the most up-to-date paper dealing with the geology - including age, stratigraphy and lithology - and vertebrate paleontology. The paper provides many new details about the Griman Creek Formation (GCF), a Cenomanian (mid-Cretaceous) formation which crops out in the area around Lightning Ridge. The GCF is a formation especially known for its diverse vertebrate paleo-ecosystem; of which many species are represented by quite a few opalised fossils The paper is also rather neat as it contains a nice overview of all the vertebrate groups represented at the GCF - an overview complete with a comprehensive (and up-to-date) list of vertebrate taxa, and several nice pictures of opalised vertebrate fossils Finally, the paper also indicates that a new ornithopod genus (Fostoria) from the GCF is soon going to be published Bell, P. R., Fanti, F., Hart, L. J., Milan, L. A., Craven, S. J., Brougham, T., & Smith, E. (2018). Revised geology, age, and vertebrate diversity of the dinosaur-bearing Griman Creek Formation (Cenomanian), Lightning Ridge, New South Wales, Australia. Palaeogeography, Palaeoclimatology, Palaeoecology. Abstract: The mid-Cretaceous Griman Creek Formation (GCF), which crops out near the town of Lightning Ridge in the Surat Basin of north-central New South Wales, Australia, is noteworthy for its opalised vertebrate fauna. The fossil assemblage comprises remains of aspidorhynchid teleosts, lamniform chondrichthyans, dipnoans, chelid and possible meiolaniform turtles, leptocleidid-like and possible elasmosaurid plesiosaurians, anhanguerian pterosaurs, titanosauriform sauropods, megaraptoran theropods, ankylosaurians, several forms of non-iguano- dontian and iguanodontian ornithopods, crocodylomorphs, enantiornithine birds, and stem and true mono- tremes, making it one of the most diverse mid-Cretaceous terrestrial vertebrate faunas in Australia. A detailed stratigraphic survey of twenty subterranean opal mines provides new information on the geology, age and pa- laeoenvironment of the main fossil-bearing beds. Vertebrate remains derive from the ‘Finch Clay facies’, lat- erally-extensive but discontinuous lenses of claystone that likely accumulated relatively rapidly in near-coastal but freshwater embayments (i.e. lagoonal conditions), and probably represent a single, roughly con- temporaneous fauna. U-Pb age dating of detrital zircons extracted from a distinct layer of volcanogenic claystone immediately overlying one of the opalised fossil-bearing layers yields a maximum depositional age of 100.2–96.6 Ma. These new dates confirm an early to mid-Cenomanian age for the fauna, rather than Albian, as has been reported previously. The GCF at Lightning Ridge is therefore equivalent to the middle part of the Winton Formation (Queensland) and several million years older than the sauropod-dominated fauna at Winton. For those who want the paper, PM me your email address and I'll send it to you -Christian
  20. Mikrogeophagus

    Meristodonoides sp. Spine, Rush Creek

    From the album: Woodbine Formation

    Meristodonoides sp., North TX Cenomanian, Cretaceous Jun, 2023 Surprisingly common in this pocket. I've found 3 fragments in a single hunt, this being the largest. I chose the genus Meristodonoides because those are the only Hybodontiformes teeth I've found so far.
  21. Mikrogeophagus

    Cretodus semiplicatus, Rush Creek

    From the album: Woodbine Formation

    Cretodus semiplicatus, North TX Cenomanian, Cretaceous Jun, 2023 Cretodus semiplicatus is a species that inhabited shallower waters, meaning they are a common sight in the near shore Woodbine along with Meristodonoides sp. and Onchopristis dunklei.
  22. Mikrogeophagus

    Woodbinesuchus byersmauricei, Rush Creek

    From the album: Woodbine Formation

    Woodbinesuchus byersmauricei, North TX Cenomanian, Cretaceous Jun, 2023 The only croc described from the Rush Creek Member of the Woodbine. Unlike most modern crocs, Woodbinesuchus had an extremely narrow snout with long teeth adapted for a diet of fish. The closest thing today is an Indian gharial. The croc teeth are apparently quite abundant at my site. Easily some of my favorite teeth ever.
  23. Mikrogeophagus

    Onchopristis dunklei, Rush Creek

    From the album: Woodbine Formation

    Onchopristis dunklei, North TX Cenomanian, Cretaceous Jun, 2023
  24. Mikrogeophagus

    Cretalamna catoxodon, Rush Creek

    From the album: Woodbine Formation

    Cretalamna catoxodon, North TX Cenomanian, Cretaceous Jun, 2023
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