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The Corsicana Formation is a Maastrichtian sequence about 68 MYA that outcrops in a 350 mile long band paralleling the Balcones Fault from north to south Texas. It has contemporary exposures from the East Coast to Mexico, and I've been fortunate to collect some of these exposures in Mississippi to complement my Texas experience. Once upon a time I had 8 or 10 producing Corsicana sites in Texas; now I have nothing worth a hoot, so I'm feeling a bit nostalgic. But I did seize the opportunity during the golden years to amass quite a stockpile of material to prep...only to realize that I had more than I needed for my personal collection. I tend to have a retention bias for the flashiest fossils; however, not all fossils have to be beautiful ot have scientific significance. A fossil need not be without blemish to retain diagnostic features and other data. Coupled with the realization that I only have time to prep the stuff I plan to retain, I have been making some pretty significant donations over the last year or so. It is also worth noting that donating unprepared material may retain micro details and matrix associations that I've potentially been (unwittingly) blowing through with my scribe. The AMNH was eager to receive a bunch of ammonite and nautiloid specimens. Wright State accepted about 100 crabs (MMNS serving as repository), and I have about 50 more ready to hand off. I've donated huge numbers of various inverts to USF, probably over 1000 specimens, with another big box ready to go. There could be some undescribed species in the latter. I've made some other donations here and there over the years including Emory, Smithsonian, researchers in Europe, etc. Let's have a peek at some pics of things I hung onto in no particular order, just as they are stored on my phone.

I have been reading up on Moroccan mosasaurs and one point of confusion that I have run into is differentiating teeth from Prognathodon anceps and Prognathodon giganteus. There seems to be a great deal of overlap in their descriptions and occasional contradictions in the scientific literature. The first issue I’ve noticed is that there seems to be a great deal of confusion over what to even call the two species. Leiodon anceps (Owen, 1841-1845) was based on two tooth fragments and a section of jawbone. The genus was renamed Liodon by Agassiz (1846) because the name Leiodon was preoccupied by the pufferfish Leiodon Swainson, 1839. E.D. Cope (1869-1870) caused confusion by treating Liodon as synonymous with Tylosaurus. Further confusion was caused when the holotype material of Liodon was lost. This has resulted in authors suggesting that the Liodon is nomen dubium and all species under Liodon should be transferred to Prognathodon (Schulp et al. 2008). With regards to Moroccan specimens, Arambourg (1952) identifies prognathodontid teeth as ‘Mosasaurus’ cf. anceps. The smaller specimens identified by Arambourg have since been reclassified as teeth from Eremiasaurus heterodontus (Leblanc et al., 2012) and the larger teeth have been tentatively assigned to ‘Prognathodon anceps’. More recently, Bardet et al. 2015 suggested that the Moroccan ‘Prognathodon anceps’ may actually represent a unique species, separate from the poorly defined European M. (Leiodon) cf. anceps. Prognathodon giganteus Dollo, 1904 (holotype IRScNB R106 / formerly 3103) was defined based on an incomplete skull and postcranial skeleton from the upper Campanian of the Ciply area, southern Belgium. Note that early mosasaurs, Lacerta gigantea and Mosasaurus giganteus both share a similar specific epithet to Prognathodon giganteus but are actually both junior synonyms of Mosasaurus hoffmannii. For simplicity, I’m going to just refer to the two as Prognathodon anceps and Prognathodon giganteus. In a recent thread, @pachy-pleuro-whatnot-odon made an informative post about the two prognathodontids. I have copied it below for context. Begin Quote …This is certainly another pair of nice teeth, even if they both belong to the most common prognathodontid species found in Morocco! I'd call them both P. giganteus from my experience, although the morphology of the top-most/first tooth conforms more with Bardet et al. (2014)'s Prognathodon nov. sp., which seems to correspond most to P. anceps as defined here. However, this is where I get confused between these two prognathodontid species, as the teeth of both species seem very similar morphologically (see below images): Prognathodon (Mosasaurus) cf. anceps sensu Arambourg, figure 8 from Machalski et al., 2003. Campanian and Maastrichtian mosasaurid reptiles from central Poland (some beautiful images of M. hoffmanni teeth in this publication too, @Praefectus) (Leiodon) cf. anceps, plate XXXVIII from Arambourg, 1952. Les vertébrés fossiles des gisements de phosphates (Maroc - Algérie - Tunisie) Prognathodon giganteus, figure 40 from Lingham-Soliar & Nolf, 1989. The mosasaur Prognathodon (Reptilia, Mosasauridae) from the Upper Cretaceous of Belgium Amarabourg (ibid., p. 280-281) describes the teeth of Mosasaurus cf. anceps as follows: Or, translated (mine): Machalski et al. (ibid., p. 404-405) summarize this by stating In comparison, Lingham-Soliar & Nolf (ibid., p. 166-167) describe the teeth of Prognathodon giganteus as follows: Overall, reading over all the slight differences in termonology used, the descriptions and images given for the teeth of both P. giganteus and P. anceps seem rather similar. However, Arambourg's definition of 'Mosasaurus' cf. anceps dates to 1952, whereas Dollo defined his P. giganteus in 1904. This would seem to suggest that P. giganteus might be the senior synonym. As Arambourg based his definition on Owen's 1841 description of Leiodon anceps, this seniority may be misleading, however, with P. anceps actually being the senior. Another reason to may be given more credence to the naming of P. anceps is that, according to Wikipedia "Prognathodon giganteus, named by Dollo in 1904, is one of species with the most brief descriptions, apparently only intended to provide a name for the skeleton of the mosasaur for exhibition in the museum hall". To my knowledge, the two prognathodontid species haven't ever been synonymized, however. Quote from this thread: End Quote Below are some additional pictures and academic quotations relevant to the topic. This is the holotype skull of Prognathodon giganteus and a hypothetical sketch from Lingham-Soliar & Nolf, 1990. Compare to some Prognathodon anceps skull reconstructions originating from Morocco. As far as descriptions of teeth go, Bardet and Pereda Suberbiola, 2002 describe Prognathodon giganteus in Jordan (NOT Morocco) as: They include the following picture: Cappetta et al. 2014 described Prognathodon teeth from the Gantour basin as the following. Note that Prognathodon anceps is referred to as Prognathodon nov. sp. in this publication. Bardet et al. 2015’s review of mosasaurid teeth differentiated Prognathodon teeth by the following. E is Prognathodon giganteus. F is Prognathodon anceps. In my opinion, these teeth look like they come from the same mosasaur, but different parts of the jaw. To summarize: Character Prognathodon anceps Prognathodon giganteus Size Anterior teeth less stocky than lateral teeth (Arambourg, 1952) Teeth robust, large cones (Bardet et al. 2015) Large and robust in appearance (Bardet and Pereda Suberbiola, 2002) The teeth appear to be more or less uniform in size along most of the jaw ramus although this assessment is an inference based on an incomplete number of preserved teeth and tooth bases of the maxillae and dentaries. (Lingham-Soliar & Nolf, 1992) Recurve Anterior teeth recurve posteriorly. Lateral teeth recurve posteriorly and slightly medially (Arambourg, 1952; Machalski et al. 2002) Somewhat posteriorly recurved tips (Lingham-Soliar & Nolf, 1992) Cross-section Anterior teeth cross-section, almost circular at the neck, becomes somewhat oval and irregular towards the apex. Lateral teeth are compressed with an elliptical symmetrical cross-section (Arambourg, 1952; Machalski et al. 2002; Bardet et al. 2015) In horizontal cross-section the tooth is subcircular and bears a close resemblance to Williston's (1897) cross-section of a tooth of P. overtoni (Lingham-Soliar & Nolf, 1992, Bardet and Pereda Suberbiola, 2002) Carinae Possess anterior and posterior carinae (Arambourg, 1952; Machalski et al., 2003) They are bicarinate with subequal buccal and lingual surfaces (Lingham-Soliar & Nolf, 1992, Bardet and Pereda Suberbiola, 2002) Labial (buccal) and lingual surfaces Labial and lingual surfaces, both of which are strongly convex (Arambourg, 1952; Machalski et al. 2002) Subequal convex labial and lingual faces (Bardet and Pereda Suberbiola, 2002) Serrations (crenulations) They bear finely crenellated cutting edges that extend the full apicobasal height, both symphyseally and commissurally (Arambourg, 1952; Machalski et al., 2003) The carinae are strongly marked and pinched from the main shaft with less visible serrations (Bardet et al., 2015) Surface features Facetting is not well developed but is more clearly seen on the lingual surface. Enamel beading is present, but poorly developed (Machalski et al., 2002) Some teeth bear indistinct facets on the lingual surface (Bardet et al., 2015) Tooth surfaces are enameled and appear to be covered in very fine vertical striae. This may on the other hand be an artifact of preservation caused by cracking of the enamel. Russell (1970, p. 374) on the other hand describes the enamel in P. giganteus as smooth but he may have based his statement on Dollo's (1904, p. 213) brief comment to that effect. Kues et al. (1985) also mention fine anastomosing striae in teeth which, however, are questionably referred to Prognathodon. (Lingham-Soliar & Nolf, 1992) Anastomosing enamel especially prevalent on the blunt apical region (Bardet and Pereda Suberbiola, 2002) Pinched/unpinched carinae Their two carinae are strongly detached (Arambourg, 1952) Tooth crowns without pinched carinae (Cappetta et al. 2014) The carinae are strongly marked and pinched from the main shaft with less visible serrations (Bardet et al 2015) ***Note the contradiction Apex Higher sharper apex (Bardet et al., 2015) Blunt apex (Cappetta et al. 2014, Bardet et al 2015) Based on all this, I think the defining differences the researchers are pointing are: (1) P. anceps teeth are more laterally compressed than P. giganteus (2) P. anceps teeth have “pinched” carinae while P. giganteus have unpinched carinae (3) P. anceps teeth have a pointed apex while P. giganteus has a blunt apex (4) P. anceps teeth are less posteriorly recurved than P. giganteus teeth I’m not quite sure what to conclude. These features seem like they may fall within heterodonty or individual, ontogenetic, and sexual variation. Whether the two species can be differentiated based on cranial and postcranial elements is yet to be seen. I have not seen any attempts to synonymize the species. In my opinion, I don't think the two species are understood well enough to differentiate the them based solely on isolated teeth. I would like to hear what others have to say on the topic.

So I decided that I would finally make a point of documenting some of these back country field excursions, and made a Youtube channel to keep the videos all in one place. Here's a a rather ordinary extraction of a placenticeras ammonite found the day before we did a little field work with some paleontologists. The GoPro is a fun addition to my kit, and makes it a lot easier to document the actual process of finding and extracting these things in the field. Anyway, I'll let the video speak for itself - enjoy! (click the image to open video link)

A paper was recently published announcing the presence of Prognathodon in the Late Cretaceous chalk of Denmark. Prognathodon was a large, predatory mosasaur, well-known in the USA and Morocco, but known from other places e.g., the Netherlands. This new study is especially quite a big deal, because mosasaur fossils are incredibly rare in the Danish chalks. Prognathodon is now the 4th mosasaur known from the Late Cretaceous of Denmark, along with Mosasaurus, Plioplatecarpus and Carinodens. The Danish material is represented by two teeth - one of them being from the fossil site I study, Møns Klint! It's quite exciting that more and more research on the Late Cretaceous vertebrates of Denmark is being done The two danish Prognathodon teeth. The larger one (A-D) was found at Møns Klint, the smaller one (E-H) was found at Stevns Klint. These would have originated from 7.5- and 4-metre long mosasaurs, respectively. This is the new paper describing the mosasaur material: Giltaij, T.J., Milàn, J., Jagt, J.W.M. & Schulp, A.S. (2021). Prognathodon (Squamata, Mosasauridae) from the Maastrichtian chalk of Denmark. Bulletin of the Geological Society of Denmark, vol. 69, pp. 53–58. You can download the paper from here : https://2dgf.dk/publikationer/bulletin/bulletin-69-2021/#3 Hope you enjoyed this "Made-in-Denmark" mosasaur news -Christian

Hello all, Found these really cool fossils (some weeks ago). The fossils are from the Cretaceous period (shallow marine environment covered Limburg - part of the Netherlands). The fossils are from the upper upper Campanian and lower Maastrichtien (73-69 and/or 72-69 and/or 72-68 mya). I and my girlfriend were searching for fossils and walking in a forest when we found two VERY LARGE echinoids (Echinocorys scutata (Leske, 1778). These are really big and the best ones I have in my collection (one is 9 a 10 cm). The other one is also really big, somewhat flatter, but not complete (missing parts and bottem damaged, also the details are not that really good preserved but overall, the specimen is a very cool and good find). My girlfriend found the biggest belemnite specimen I have found in the Netherlands (one 10,5 cm Belemnitella/Belemnella sp.) (big belemnite on the right). All in all a really cool trip!

Yesterday: fossil hunting with my girlfriend in Limburg. Many Cretaceous limestones and good fossil specimens! Including a really big and complete Pycnodonte vesicularis (Lamarck, 1806). My second biggest Pycnodonte. Many belemnites (including a real cool black one!), two pieces (including a big one) from the same genus (Pycnodonte) and one sea urchin Echinocorys sp. or Echinocorys scutata (Leske, 1778). Also one recent cow/bovid tooth and a piece of vase. The two photo's on the right are from another (earlier) trip (fossils are on the ground in a field. Finds: one sea urchin Cardiaster granuloses (Goldfuss, 1829) and one belemnite (many more belemnites were found). Genus Belemnitella or Belemnella (Pachybelemnella) sp.)

Morocco keeps delivering cool new discoveries. A new small Mosasaur is described in the attached publication, its Xenodens calminechari from the upper Maastrichtian phosphates of Morocco. Paywalled https://www.sciencedirect.com/science/article/abs/pii/S0195667121000112 Teeth form a unique dental battery in which short, laterally compressed and hooked teeth formed a saw-like blade. @jnoun11 Has anyone seen teeth like these or have them in their collection?

Hey everyone I know I've been lately rather inactive on TFF; I was held back by fieldwork and other reasons (though do expect some posts about the fieldwork next weekend ). But anyway, onto what I came to talk about... Would anyone know of some good exposures of Late Cretaceous chalk in Canada or USA? I'm thinking specifically about Campanian chalk or, even better, Maastrichtian chalk.. It would be great if the exposed chalk is very fossiliferous, of course. Thanks for any help! -Christian

This topic is a short continuation of my previous topic on my Squalicorax collection, which can be seen here: This time I have chosen to show my Pseudocorax teeth. As with the Squalicorax teeth, I am open for trades and buying new additions. The oldest examples of Pseudocorax in my collection come from the Lower Campanian. Like the Squalicorax genus, they start off as a genus with very small teeth. Pseudocorax granti (x16) Ozan Formation Lower Campanian Moss Creek, Fannin County, Texas, United States of America See you guy tomorrow, Sander

Hi everybody! Last month i saw this tooth on sale and it was love at first sight But from the beginning i understood that what it was and how it be presented are not on the same page... Luckily i know the seller pretty well and we trust each other...so i asked info before make the purchase...He told me that his provider (directly from Morocco) told him that the tooth was a Dyrosaurus phosphaticus but that he was not confident about the ID...the moroccan provider told to my friend/seller that was the first time that he saw a totth like that and its first idea of ID was D.phosphaticus. So provider was not sure, the seller just report the same ID given by the provider...and after hearing this story, i was even more convinced that i was on the good path...this is NOT a D.phosphaticus tooth...but for me, it was not a crocodilian tooth at all. Then i started to wondering what could it be...and i have reached two possibilities: 1) Spinosauridae: like Baryonyx/Suchosaurus 2) Pliosauridae: like Liopleuridon or Simolestes The specific features of the tooth (well conserved on labial side, damaged on lingual side, full carinae, intact root) are: - 2 marked, smooth carinae - 9 labial ridges - less evident lingual ridges - smooth enamel Other info: Origin: Khourigba - Morocco Age: Maastrichtian - Upper Cretaceous (doubtful) Lenght: 5.5cm / 2.16 inches What do you think about it? Someone can recognize it? Let me know and thanks to everybody!

The first Hadrosauridae from the Maastrichtian of Morocco is described in this paper. Pretty cool, its a lambeosaurine called Ajnabia odysseus. From Ouled Abdoun Basin. Its also the first named hadrosaur from Africa. Hopefully will see some teeth on the market. Sorry its Paywalled https://www.sciencedirect.com/science/article/abs/pii/S0195667120303657 See below for additional images

Every few years we get rewarded with a new dinosaur described from the Lance/Hell Creek Formations. In this crazy year we finally have one. Finally an Alvarezsauridae has been described from the Hell Creek Formation: Trierarchuncus prairiensis. Sorry its paywalled cannot make comments https://www.sciencedirect.com/science/article/pii/S0195667120302469 Here is some info on this very different dinosaur, one of my favorites, including some of my material so you can see what the paper is describing. Far better than what you see in the paper

The skull of any dinosaur is composed of many different elements. When I go collecting in an Edmontosaurus bonebed one never finds a skull but the elements that make up one up. Like to use this topic to share the complexity and variety of some of the elements I have collected. I do not have many but will post the ones I have and will continue to add as I prep or find them. Of course if anyone sees any discrepancies please feel to comment and like to thank Olof (LordTrilobite) in the ID of some. Skull still in a jacket not from my usual bonebed but one can see it all together. One day I'll get it mounted. To aid in identification of where SOME these elements are located have this illustration that comes from Marsh's 1893 This is a Saurolophus skull but elements are the same QJ: Quadrotojugal PMX: Premaxilla L: Lacrimal SA: Surangular SQ: Squamosal PO: Postorbital EO: Exoccipital Dentary (Less Teeth ) The Maxilla Surangular Squamosal Quadrotojugal Exoccipital Quadrate \ Splenial