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  1. Ancient frog had a belly full of eggs in oldest fossil discovery of its kind. This unusual frog fossil seems to be an amphibian that died in the process of mating by Matthew Rozsa, Salon February 9, 2024 The open access paper is: Baoxia Du, Jing Zhang, Raúl Orencio Gómez, Liping , Mingzhen Zhang, Xiangtong Lei , Aijing Li, and Shuang Dai, 2024, A cretaceous frog with egg from northwestern China provides fossil evidence for sexual maturity preceding skeletal maturity in anurans. Proceedings of the Royal Society B, Biological Sciences, https://doi.org/10.1098/rspb.2023.2320 Yours, Paul
  2. Today I took a spur of the moment trip up to the Canyon Lake area for some hunting in the lower Glen Rose. My first venture into the region took place last year and was only a limited success in that I scored a measly two micro echinoids. The plan for today was to try some new spots in hopes of striking the perfect layer of echinoid diversity. The first site was a complete bust, but the second immediately showed promise when I noticed the ground was littered with broken bits of thin echinoid test. Because I had arrived so close after the recent rains, the ground was still a sticky slop of Glen Rose mud. The combination of running along the slopes and frequent crouching set my calves on fire, but the scent of urchins kept me on the chase. Very quickly I was lucky to encounter some really nice crab claws from Pagurus banderensis. A couple had both pincers still preserved. Surprisingly common was also the tiny crushing dentition of Pycnodont fish. They aren't all that interesting to look at, but the simple fact that vertebrate material was present gave me daydreams of finding an elusive Glen Rose shark tooth. I tried to shake away such a hopeless goal, but it continued to sit in my mind. After a couple hours, I found an Amiid fish tooth and some star-shaped Isocrinus annulatus columns. For whatever reason, I could not find a single echinoid spine, let alone a complete test. I was searching the ground very closely, so my thinking was it may be more to do with the site than myself. As I was doing the usual close inspection, I snuck up on a black figure nestled securely in a pile of Glen Rose matrix. It took a moment to register that I wasn't looking at just another chunk of black bug. I safely stashed the two pieces of Polyacrodus. Sadly, the third fragment was nowhere to be seen despite my best efforts. After finding some more crab claws it was time to head out. On the trek to the car, I spotted a Trigonia whitneyi? clam, maybe from the upper Glen Rose. I'm not sure what species this is. I see Polyacrodus aff. parvidens is described form the Texas Albian up north. Other than that, there doesn't seem to be much info. I've seen some discussion on Polyacrodus brevicostata being a possibility as well. Top L to R: Trigonia whitneyi? and Pagurus banderensis Bottom L to R: Amiid tooth, Pycnodont teeth, Isocrinus annulatus It seems my streak of urchin unluckiness has continued, but I'll take a Polyacrodus any day of the week!
  3. Spent some time yesterday driving around Fort Hood military base area. I didn't go inside the main base, but there were plenty of public roads and lands next to the base that were not fenced in or restricted. I managed to find few spots that were exposed to the erosion. Most fossils were bivalves, gastropod and lots of broken oxytropidoceras ammos. Due to nature of the preservation most Oxy's were broken. West Fort Hood in the background. Road leading to Fort Hood gate. Exposed Walnut Formation surface. Gryphaeas were everywhere! Collection. This is the biggest Oxy ammo I've ever found in Texas. It measures almost 13 inches.
  4. I've been searching through lots of different North Texas micro matrix for a project and came across a little tooth that has me stumped. It's from the Duck Creek Fm (Albian), Washita Group. From the same matrix I've collected several Scyliorhinus arlingtonensis (this species is previously known from the Texas Pawpaw and Woodbine), which look similar in some aspects. However, there are distinctions that push to me wonder if this other tooth is something different. Here are some photos of the mystery tooth. I found another of the same species in worse condition as well. Mystery tooth For comparison, here is a photo of a solid Scyliorhinus arlingtonensis of which I have found several from the same matrix. Scyliorhinus arlingtonensis Why it could be Scyliorhinus arlingtonensis: I know cat sharks can exhibit a high degree of heterodonty, so that could be the culprit. Both sets of teeth have ridges on the basal portion of the labial face, as well as multiple pairs of cusplets. Both also have very flat basal root faces that flare out at the lateral ends underneath the cusplets. Why it could be something else: Only S. arlingtonensis appears to have ridging on the lingual face, and the ridging reaches quite close to the tip. On the mystery tooth, I don't see any such ridging on the lingual side. The roots vary as well. S. arlingtonensis has a root that more closely resembles a "mickey mouse head". The lateral portions of the root flare out more, like mickey's ears and the bulbous lingual apex like mickey's face. The mystery tooth, on the other hand, is more v-shaped and the lingual apex of the root nowhere near as bulbous. Furthermore, S. arlingtonensis has a strongly pronounced central foramen (the little hole at the end of the lingual apex). I don't see this feature in mystery tooth. In S. arlingtonensis, the central is cusp long, gracile, and more separated from the adjacent cusplets. The mystery tooth has a robust central cusp and is joined with the cusplets much farther up. The second pair of lateral cusplets are also much larger. I have had a tough time trying to find species online that match my specimen in every aspect. It most definitely looks closest to cat shark, but everything I've come across just misses the mark. One interesting genus was Pseudoscyliorhinus, which has large pairs of secondary lateral cusplets like mine, but again there are some major differences in things like root shape. Hopefully one of you all have some ideas or at least new leads for this case. @Al Dente @siteseer @MikaelS @MarcoSr @ThePhysicist Feel free to tag anyone I missed Thanks for reading
  5. We are currently looking for rare rare Ammonites from Courcelles / France like Oxytropidoceras and heteromorph ones could be unprepped but must be complete and (if unprepped) possible to be in great condition after prepp (I know thats always a risk) PM if you like to offer some, thanks
  6. Echinoid Express

    Macraster elegans Assemblage

    From the album: My Echinoid Collection

    Macraster elegans Assemblage Duck Creek Formation Albian Age, Early Cretaceous (102-100 Ma) Grayson County, Texas, USA Acquired from a collector during a local trade show, September 2023
  7. Mikrogeophagus

    Paraptychodus washitaensis, Medial Tooth

    From the album: Duck Creek Formation

    Paraptychodus washitaensis, Medial Tooth, North TX Albian, Cretaceous July, 2023 For sure a top 3 shark tooth in my collection. The crown is in pristine condition and measures just over 15 mm across with a crown height of 10 mm! Sadly the root is chewed up unlike my lateral specimen.
  8. Mikrogeophagus

    Paraptychodus washitaensis, Lateral Tooth

    From the album: Duck Creek Formation

    Paraptychodus washitaensis, Lateral Tooth, North TX Albian, Cretaceous July, 2023 My best Paraptychodus in terms of root preservation. One of the most interesting features that distinguishes this genus from Ptychodus is the fact that the lingual sulcus and labial protuberance are absent from the crown. Instead, those characteristics are present within the root which is an ancestral condition that tells us a lot about their evolution. These specialized roots would interlock the teeth whereas later Ptychodontiformes had rather featureless roots that lost this function.
  9. Mikrogeophagus

    Paraptychodus washitaensis, Posterior Tooth

    From the album: Duck Creek Formation

    Paraptychodus washitaensis, Posterior Tooth, North TX Albian, Cretaceous July, 2023
  10. Mikrogeophagus

    Indeterminate Turtle

    From the album: Duck Creek Formation

    Indeterminate Turtle Vert., North TX Albian, Cretaceous July, 2023
  11. These past few days, I've been running around North Texas to a handful of sites, some old some new. The reason for occasion was the arrival of a couple of our own forum members to the DFW metroplex, my current stomping grounds. I was excited to show off a few of my favorite sites and have the opportunity to explore something new in a short span of time. One of my first forum friends ( @Jackito ) had some work to do in Dallas along with a couple afternoons to kill for fossil hunting. I decided to take him to a couple of spots that had fossils unlike anything found down in Austin. Our first stop was at my new Woodbine outcrop one sunny evening. The pocket did not disappoint this time around and Carter found himself a nice Cretodus, Cretoxyrhina, and several croc teeth! I didn't have the most luck, but I've got a baggie of the rubble that is promising for micros or so I hope. We finished the final hour of sunlight at my ole Pawpaw site. I was hoping we could score a bunch of crab carapaces, but we got a bit skunked in that department. Plenty of complete Engonoceras ammonites and crab claws were had at least. I sent Carter off to a Kamp Ranch site for the following day. I haven't seen his finds from there just yet, but I heard it was a good hunt. Another forum member friend, @LSCHNELLE coincidentally visited DFW this weekend. Anyone familiar with him knows that he is the craziest ptychodus fanatic on the forum. He and I had been planning a Paraptychodus expedition for awhile and Saturday was set to be the day. Before that though, we made a visit to my Atco site in hopes of scoring some Early Coniacian Ptychodus. Sadly, we got completely skunked and almost had serious trouble when a giant tree limb fell just feet away from us. A Long Story Short Lee had some secret intel on a possible site where we could find the elusive Paraptychodus washitaensis, the oldest species of Ptychodontiformes. When we met up, I told him I had a good feeling about our chances to which he agreed. We spent the morning walking around the place looking for any indication that we were in the right area, but nothing seemed to match. After finding a whole lot of nothing three hours in, I could sense that we were both beginning to feel defeated. Instead of calling it quits there, however, we decided to change our focus and take a long shot at another spot. As we walked along the new outcrop, I searched the exposure while Lee poked through the talus. Things were going smoothly as we began to find the usual Duck Creek stuff including a pretty little shark tooth. The atmosphere was very serene, but that took a quick turn when I heard Lee excitedly shout, "PARAPTYCHODUS!". I almost couldn't believe it at first, but then I saw the unmistakable transverse ridges of the oldest Ptychodontiformes known to science. We were filled with a renewed energy and got straight back to hunting. Pretty soon I came across my own smaller Paraptychodus specimen and an extra half of a tooth on top. After a handful of smaller shark tooth discoveries we were nearing the end of Lee's visit as he had a long way to go back to Austin. We turned around and started making our way back the route we came. The majority of the fossils had been in the talus, but I took an ambitious path looking at the exposure. I focused on a darker spot of interest in the wall that I had initially written off as just another oyster. As I looked closer, I saw its wrinkled surface and hollered for Lee to come over. In my hands was a pristine and quite large Paraptychodus tooth! It was more than anything I could've hoped for! My best Paraptychodus washitaensis (mesial tooth) My first Paraptychodus washitaensis. Note the preserved root Posterior Paraptychodus washitaensis A vert I think is sea turtle? A strange fish jaw. Any ideas?
  12. Taxonomy from Fossilworks.org Species diagnosis from Nakamine et al. 2020, p. 20: "Protibia five slight protrusions on the proximal area of ventral ridge, bearing two spines on the distal area of ventral ridge (three in M. cristata). Hindwing RP divided into five branches; one intra-RP crossvein (4rp4-rp5) present." Line drawing of (d) left forewing; (e) right forewing; and (f) left hindwing from Nakamine et al. 2020, p. 21; Scale bar 1 mm. References: Nakamine, H., Yamamoto, S., & Takahashi, Y. (2020). Hidden diversity of small predators: New thorny lacewings from mid-Cretaceous amber from northern Myanmar (Neuroptera: Rhachiberothidae: Paraberothinae). Geological Magazine, 157(7), 1149-1175. doi:10.1017/S0016756820000205
  13. Mikrogeophagus

    Holaster simplex

    From the album: Duck Creek Formation

    Holaster simplex, Tarrant Co. Albian, Cretaceous Apr, 2023
  14. 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
  15. Return to the Badlands of North Texas At long last, rain graced the lands of North Texas this past week. For many of us, that meant it was time to finally crawl out of bed and beat the crowd to that one particular site desperately needing a refresh. In my case, I set on my way to explore a newer spot in the Grayson Marl while the ground was still nice and muddy. I'd been to this place once before, but it had already been thoroughly picked over. It's a popular site, but even then, it managed to pull through and produce some fine specimens for me to take home. With that in mind, I suited up in preparation for a very wet and very, very cold day in the "badlands" of North Texas. As I took my first step out of the car, my foot was immediately enveloped by a Grayson Marl pudding. I don't own boots, so my measly tennis shoe was suctioned off as I tried to wriggle free. Although the moistened marl was a hassle to trudge through, I quickly reassured myself that such a characteristic would be a benefit in terms of eroding new fossils and continued on my way. By the time I reached the spot, I was practically walking atop 6-inch platform shoes made of the stickiest mud known to man. It was no use shaking it off, so I accepted the burden of having to walking like a newborn giraffe for the rest of the day. Out in the distance, I could just make out a person with a bright orange beanie. Clearly, they too were chasing fossils after the rain. Luckily, the site was quite large, so there was plenty of room for both of us to graze. Still being unfamiliar with the locality, it took a while for me to adjust my eyes to hunting. The ridiculous number of fragmented shell bits and corroded pyrite fossils made it difficult to filter the noise out. However, the knowledge of what could be found kept me motivated. Eventually my efforts were rewarded with the first decent find of the day: A nicely sized Cretalamna Cretalamna catoxodon Soon after, I happened upon an area with a mess of brittle star limb fragments. I searched very thoroughly for a central disk, but nothing could be found, so I decided to swipe only a single piece. Keeping in the theme of weathered finds, I also spotted the most complete Coenholectypus I'd ever come across there. Though it looked nice, I again decided to leave it be. Few fossils are worth that much of a headache to consolidate! Coenholectypus castilloi? Already, a decent chunk of time had elapsed and I was a little discouraged with the lack of weight to my baggie. Meanwhile, the man in the bright orange beanie had steadily made his way closer to the area I had been working. It seemed he was about to finish up his session, so he walked over and introduced himself as Mike. Apparently, he is an admin for the Texas Fossil Hunting group on Facebook. Though he hunts all over the place, the site we were standing in was his main spot he had been visiting for three years! We had a nice conversation about the Grayson Marl as well as a handful of famous places around the state. Since ptychodus was my ultimate goal for the location, I also inquired as to how many he had found here in the badlands. For the span of three years, only two small specimens were to show. With numbers like that, I figured I better not get my hopes up. He showed off a few of his nicer finds from the morning, including dozens of tiny Goniophorus scotti, before saying goodbye and heading out. I still had a final stretch I wanted to check out, so squatted down and quickly got back to work. I think something about seeing his collection helped me to see things more clearly. I rapidly spotted several more C. catoxodon teeth after our encounter. However, I was most excited to find my first Squalicorax from this formation, despite its miniscule size. I know identification for this genus is quite convoluted, but I felt it had a likeness with S. baharijensis because of its broad neck, well developed serrations, and other features. Squalicorax baharijensis? To round off the day, I looked through one last mound of marl and spotted a very strange and distorted figure. It looked as though some larger fossil had been broken into rubble. I picked up a chunk and observed a texture I was not used to seeing. After taking a moment to process what exactly I was looking at, I realized it was the surface of a heart urchin, likely Hemiaster calvini, with the spines still articulated! I quickly began gathering the pieces in the immediate area in case they were from a single organism I could puzzle back together. At the time they were covered in mud, so I did not realize that they were from many individuals likely eroding from a single layer. At home, I put them under the microscope and found some interesting features generally unobservable in most spatangoid specimens. Have a look: A lot of times it's easy to forget how deeply similar irregular urchins are to their regular counterparts. With the naked eye, it's impossible to observe this level of detail in the tubercles of a spatangoid. However, at the microscopic level, we can see that they are alike. These tubercles, in my amateur opinion, are just like that of a salenia or cidarid species. My favorite observation was the presence of the articulated spines of course. Something I did not expect was their morphology. The bottom 2/3 of the spine appears to be longitudinally ridged and has a black color. The top 1/3 transitions to a yellow coloration while also beginning to flatten out into the shape of a shovel. Also, the spines seem to generally point away from the front of the urchins. I'm sure some of the resident echinoid experts on here are already well familiarized with the shovel shape of these spines, but I was quite intrigued. I already knew that irregular echies travel under substrate, so I began to wonder if these spines perhaps served a function that related to their lifestyle. If you haven't yet had the "aha moment", it appears that spatangoids use these shovel spines to help dig and move their bodies while buried! Hopefully this little tangent helped to enrich your appreciation for irregular echies as it did for me ! Anyways, by then I had had enough of the Grayson Marl and was ready to check out some other sites that were preferably a little easier to navigate. So I packed my things and headed for the car. But first, here is an overview of the Grayson Marl Finds: Hemiaster calvini with articulated spines. The one at the top seems to be complete, though completely flattened. The bottom chunks are from many individuals. I have many smaller pieces not pictured. From afar, they have a "fuzzy" texture. Top L to R: Ophiura graysonensis limb frag, Stereocidaris hemigranosus plates, S. hemigranosus spines (cool), and Parasmilia graysonensis solitary corals. Bottom L to R: Bivalve, bivalve, Neithea texana scallop, unknown fossil with interesting bumpy texture (perhaps decapod), and Mariella bosquensis heteromorph ammonite. Top L to R: Cretalamna catoxodon, Squalicorax baharijensis?, Cretoxyrhina vraconensis? (more on this at end of the topic), and Cretalamna catoxodon. Bottom L to R: Various verts, Xiphactinus tooth? (no cutting edges - always wonder if these could be pterosaur), and fishy bits. ~ ~ ~ Some Say Lightning Doesn't Strike the Same Place Twice... Well, the original plan was to scope out two new Pawpaw sites in the area, but, in my exhausted state, I decided to say screw it and take a trip to my favorite spot in the Pawpaw. It's been said that you shouldn't go looking for fossils when you've already found them, so what was the point in risking my time and energy when I could see what the rain had swept out at ole reliable. When I got to the exposure, I went straight for the productive layer and instantly had a field day with a plethora of micro ammonites. I'm guessing since they had limited exposure to the atmosphere, they were still shiny and easily spotted. It was definitely the best luck I'd had for cephalopods so far at the place. The first picture-worthy find was an exceptionally preserved central disc to a brittle sea star. I could tell it had eroded from a layer different to the previous starfish I had found. Unfortunately, there was not even a single associated limb fragment in sight. The aboral side appears to differ from that of Ophiura graysonensis. It is difficult to compare with O. texana of the Weno since the only picture I could find of the type specimen is blurry and the fossil itself hard to make out. So, I'll stick with Ophiura sp. for now. Periodically I came across more fantastically preserved crab carapaces. It seems every hunt at this site, I find one beautiful Feldmannia wintoni carapace and this visit was no different. In the past, the better Steorrosia crabs I gathered tended to be S. aspera, but this time, I finally collected a couple great S. pawpawensis specimens including my second carapace with preserved eyes! The fierce compound eye of Steorrosia pawpawensis! Vertebrate fossils are tough to come by, so any shark tooth is a welcome site. The one pictured below had an amazing purple tint that sadly did not stay after being cleaned. It was my first Squalicorax from the Pawpaw, so I knew I was adding a new species to my collection. After some research online, I believe it to be Squalicorax priscoserratus on the basis of its thin neck, dense root, and well-developed serrations. Squalicorax priscoserratus I hadn't been hunting for long when I began to tire. Since the ground was so muddy, I didn't have the chance to sit and hunt like I usually prefer to do. On top of all the squatting, staying right side up on the slippery muck created additional strain. I decided to finish up a little early and save some of the site for a future day when the conditions were drier. I set a location in my mind for where I would call it quits - the area I had found the articulated brittle sea star in my last visit. Of course, I would be crazy to expect a repeat of such a legendary find, but I would be lying if I said the thought wasn't hanging over my head throughout the final 15 minutes of the day. In parts of medieval Europe, heart urchins were once known as "thunderstones" for their supposed creation at the place of a lightning strike sent by a god. They were magical items collected and often cherished by those who hoped to find connection with the heavens. In modern times, such beliefs are easily dismissed, but that isn't to say that the same curiosity and admiration those distant peoples felt for these treasures has eroded away in the slightest. As I approached the location of where the last articulated sea star had been found, I began to wonder if the fossil gods may have cast another bolt in my favor. Kneeling down for one last time, my eyes were embraced with the sight that sent me straight back to my feet. Although the ground didn't show any apparent signs of burn marks sparked by the wrath of Zeus, I was face to face with something I thought I would only find in dreams. A horde of 15 brittle star limb fragments surrounded a single yellow central disc. For reference, my last star had only 4 limb fragments! To any passerby, I looked crazy with the number of fist pumps I was doing. I made sure to gather as much as I could and headed for the car, though I was definitely not in the right head space to be driving . In situ. Doesn't look like much yet! The consolidating process was tedious as expected. Thankfully, my last project had given me some much-needed practice that made the process much easier than it could have otherwise been. With each attachment, the delicate figure of this animal could be more thoroughly appreciated. Once it was complete, I took way too many pictures, but can you really blame me ? Brittle sea stars old and new This is my new favorite in my collection! I'm almost afraid to return to the spot because I know it'll be a let down from this... though on second thought I guess I'm not afraid enough to stay away. Overview of Pawpaw Formation Finds: Top L to R: Cantabrigites wenoensis, Engonorceras serpintinum, and Stoliczkaia asiatica. Bottom L to R: Neophlycticeras sp., Enigmaticeras riceae, Scaphites hilli, Stoliczkaia worthense, and Conlinites wrighti. Not 100% on some of these IDs but based off of overall morphology and suture patterns shown on a publication, these are the names I've somewhat confidently come up with. Top L to R: Steorrosia aspera (the one on the right is oddly shaped and could be something entirely different), Feldmannia wintoni (beautiful blue coloration), and Steorrosia pawpawensis (The one on top has the preserved eyes). Bottom L to R: Various decapod fragments. A look at the undersides of (L to R) Steorrosia aspera, Feldmannia wintoni, and Steorrosia pawpawensis. A close up of the spines on one of the claw fragments: Top L to R: Squalicorax priscoserratus, and Haimirichia anomensis (Even though this is upper Albian and not Cenomanian, I assume this newly described genus applies to this tooth since Eostriatolamia anomensis/Carcharias anomensis were previously known from the Pawpaw). Bottom: Fish parts Brittle stars of the day, oral and aboral sides: ~~~ Questions Just to round off the post, I have some questions regarding identifying teeth from the Pawpaw and Grayson (Late Albian and Early Cenomanian). Specifically, I have confusion when distinguishing between Cretalamna and Cretoxyrhina. About a month ago, I found a tooth in the Pawpaw that I think strongly resembles Cretoxyrhina vraconensis. During my recent hunt in the Grayson, I picked up a couple of damaged teeth that seem to usually be identified as Cretalamna online, but I think share a resemblance with my Pawpaw Cretoxyrhina specimen (similar tiny splayed cusplets and a large, protruding root). So, I am wondering if any of you can help to clarify. Are these teeth also Cretoxyrhina or simply more Cretalamna? I may even have my Pawpaw tooth misidentified for all I know. L to R: My Pawpaw "Cretoxyrhina vraconensis", two unknown teeth from the Grayson (Cretalamna catoxodon or possibly Cretoxyrhina denticulata/C. vraconensis), and lastly a pretty obvious Cretalamna catoxodon from the Grayson. Feel free to let me know if you would like additional pictures or @ some who might know a thing or two! Thanks for reading!
  16. Mikrogeophagus

    Cretoxyrhina vraconensis

    From the album: Pawpaw Formation

    Cretoxyrhina vraconensis, Tarrant Co. Albian, Cretaceous Dec, 2022 Originally had this down as Leptostyrax macrorhiza, but decided Cretalamna appendiculata was a better match after having a second look (lack of wrinkling on labial surface). Edit: Apologies for changing so much. I did a little more research, and it appears that Cretoxyrhina vraconensis is a much better ID.
  17. Mikrogeophagus

    Cretacoranina punctata

    From the album: Pawpaw Formation

    Cretacoranina punctata, Tarrant Co. Albian, Cretaceous Apr, 2023 Cretacoranina is a type of "frog crab" which are still around today and are known to bury under the sand with their modified claws. They keep their eyes above the sand and ambush prey. Unlike most other crabs, frog crabs do not have their abdomen tucked beneath their cephalothorax. The frog crab fossil record starts in the Albian which means this specimen is very close to their supposed origin! I actually found the posterior end of this crab a couple of months ago. I knew it was from this species which is a bit rare so I held on to it. Then I came across the anterior portion earlier this week and was excited to find that the pieces fit together perfectly.
  18. Mikrogeophagus

    Goniophorus scotti

    From the album: Duck Creek Formation

    Goniophorus scotti, Tarrant Co. Albian, Cretaceous Apr, 2023 Scoped out my first Duck Creek site that wasn't all the way up in Texoma. I was surprised to find it had a micromorph zone complete with pyritic ammonites and this tiny echinoid. Fingers crossed it might have some sharks teeth too.
  19. Jared C

    Tetragramma sp.

    From the album: Texas Albian (Cretaceous)

    Tetragramma sp. Albian Texas Found at site #14, dubbed by my step brother and I as the "Anti-wishing well" - but it sure seems like a wishing well to me! It's a tiny site at the base of an ephemeral waterfall revealing comanche peak shales - a lithological feature I was unaware of being possible in the comanche peak until the site's discovery.
  20. Mikrogeophagus

    Steorrosia reidi

    From the album: Pawpaw Formation

    Steorrosia reidi, Tarrant Co. Albian, Cretaceous Jan, 2023 Surprisingly rare amongst my decapod finds. This one was found broken in half. It's my best specimen as of yet. Distinguished by its unique style of granulation on the carapace.
  21. Mikrogeophagus

    Acanthaxius carinatus?

    From the album: Pawpaw Formation

    Acanthaxius carinatus?, Tarrant Co. Albian, Cretaceous Feb, 2023 Fossil mudshrimps of the Pawpaw are special finds and are easily overlooked. This is my first specimen, but it is missing much of the carapace so identification is difficult.
  22. Mikrogeophagus

    Squalicorax baharijensis

    From the album: Pawpaw Formation

    Squalicorax baharijensis, Tarrant Co. Albian, Cretaceous Feb, 2023 Squalicroax baharijensis on the basis of broad neck and well developed serrations (?). Could be wrong with the serrations. If they are "poorly developed", S. pawpawensis would be the better ID.
  23. Mikrogeophagus

    Leptostyrax macrorhiza

    From the album: Duck Creek Formation

    Leptostyrax macrorhiza, Grayson Co. Albian, Cretaceous Jan, 2022 A huge tooth found by my brother from the shores of Texoma. It has a height of 31 mm!
  24. Mikrogeophagus

    Cretalamna catoxodon

    From the album: Duck Creek Formation

    Cretalamna catoxodon, Grayson Co. Albian, Cretaceous Jan, 2022 The only Cretalamna species I can find described from the Albian is C. bryanti. However, I don't see much resemblance with my specimen. C. catoxodon is found in the Cenomanian and looks similar, but it is possible this tooth may belong to some undescribed species.
  25. Mikrogeophagus

    Lechites comanchensis

    From the album: Pawpaw Formation

    Lechites comanchensis, Tarrant Co. Albian, Cretaceous Dec, 2022
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