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  1. Hello all, I need some help with the ID on this bit of bone I found this evening in the Kef-Kau transition zone off the near the Denton-Collin County border, If anyone has ever hinted this zone/area you know that it's full off sharks' teeth, vertebra and plenty of bone fragments like fish jaws, this is the first piece of simi recognizable bone I've found in a good while that I have no idea on what to ID it as. Thanks for any help anyone can give me.
  2. Hi, Any help greatly appreciated. Went on a club trip with the Dallas club, mostly looking for shark teeth in a club sponsored trip to a private cement quarry south of Dallas, Texas. Found shark teeth (Scapanorhynchus, Squalicoraxs, Ptychodus), but also found this odd thing. I have cleaned all the extraneous material off of it (with a dremel using a wire brush) and the remaining is hard and fossil like, but a real puzzler. I have included a back and front photo. It was in gray material that had phosphate nodules and small shark teeth. Thanks, Rick
  3. Jared C

    Hadrodus cf. priscus

    From the album: Texas Campanian (Cretaceous)

    Incisor in a portion of premaxilla from Hadrodus cf. priscus. The teeth are not diagnostic to species, and current unpublished research has questions about the validity of certain species within the genus - not my place to discuss openly just yet Though I used to have this in my Santonian album, closer investigation of the geology of the site has led to a pretty conclusive lower Campanian age. Close the the Austin Chalk/ Ozan boundary
  4. From the album: Texas Campanian (Cretaceous)

    cf. Stereocidaris, with possible affinities to S. sceptrifera Lowermost Campanian TX This Cidarid seems to have affinities with Stereocidaris sceptrifera from the late Cretaceous of Europe, but the geographic separation and lack of literature on this new world form suggest a potential undescribed species of Stereocidarid. This is the same taxon as the other Cidarid in this album - both were found the same day, at the same locality Notice the partial aristotle's lantern (mouth), as well as a few of the short, flattened scrobicular spines (which protect the muscles of each primary spine) attached near the bottom. Though crushed, this specimen is excellent. Huge thanks to @JohnJ for the excellent photos, and both John and @Ptychodus04 for the prep Discovered April 1, 2022
  5. From the album: Texas Campanian (Cretaceous)

    cf. Stereocidaris, with possible affinities to S. sceptrifera Lowermost Campanian TX This Cidarid seems to have affinities with Stereocidaris sceptrifera from the late Cretaceous of Europe, but the geographic separation and lack of literature on this new world form suggest a potential undescribed species of Stereocidarid. Huge thanks to @JohnJ for the ID tips and excellent photos and @Ptychodus04 for the prep. Discovered April 1, 2022
  6. Creek - Don

    Central Texas Gastropods

    Spent Saturday looking for fossils in the Central Texas area. Came across huge chunks of rocks near the road. I decided to take a closer look. To my surprise saw loads of fist size gastropods embedded in huge stones. Interesting to see large size gastropods concentrated in a single spot like that. I usually see one or two at the most. I was also in the Walnut Formation, but these rocks may come from the Edwards formation or Austin Chalk formation. I'm leaning more toward the Edwards Formation.
  7. kaleidoscopica

    Teeth? New to teeth IDs. Austin, TX

    I am very new to fossil hunting... this started all of a sudden after I basically tripped on a big Exogyra ponderosa in my local creek the other week, and got curious what else was out there. So I've just scooped through a bunch of gravel in Brushy Creek here and found a lot of little things that I wonder what they could be. 1. Tooth? (First two photos, front and back) 2. Smaller tooth? (Single photo) 3. Maaaaybe a tooth as well, or just an exceptionally pointy rock? (Last two photos) Thanks -- let me know if any other photos or info is needed. Next time I'll use a ruler .
  8. 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.
  9. Mikrogeophagus

    Basal Atco Double Reptile Trouble

    Took a short visit today to my Basal Atco site for the third time. Seems like every visit yields something new and totally unexpected (first visit = Acrotemnus prearticular tooth, second visit = huge assoc. fish verts, and now these). I'm fairly confident both of these are reptilian, but unfortunately I don't know much about identifying tetrapods. The first specimen I found is now my only non-Campanian mosasaur tooth. It's quite small (1 cm tall) and broke into 3 pieces, but the b72 seems to have done the job in making it presentable. Not amazing quality as expected for the Basal Atco, where much of the material is reworked. I'm not completely familiar with the genera present in the earliest Coniacian. I have read about a chunk of Tylosaurinae maxilla being found near if not in the Basal Atco of Grayson county and the subfamily is thought to have started in the Lower Coniacian altogether. I want to say Russellosaurus made it to the Atco although I believe my tooth is a little large for this ID. I think Clidastes was also around in the Coniacian, although not sure how early. And there's a lot of genera I am not mentioning, so hopefully someone in the know can fill in. The tooth itself seems to have both a mesial and distal non-serrated carina. The enamel isn't faceted as far as I can tell. I know it's not much to go off of and a precise ID is unlikely, but my hope is to at least cross off some of the genera that don't fit the description with yall's help. Mosasaur tooth (1 cm tall) Going from a relatively old mosasaur, the second specimen is a surprisingly young Coniasaurus (or so I think). This might be surprising to some, but Conisaurus is found beyond the Cenomanian. It actually has been documented to extend through the Coniacian all the way into the Middle Santonian (though the documentation is few and far between I must admit)! In other words this is a rare sort of find, but not necessarily unheard of. I don't believe any species have been named extending past the Turonian, so this may be an undescribed species. My specimen has that classic bulbous shape as well as textured enamel. It sure pays to look closely at every chunk of matrix. Coniasaurus sp.? (3 mm tall) One thing I would like to note is that I have since found a paper that helped to clarify the geology of this site which was a point of confusion in my previous trip reports. I made the mistake of referring to this place as the "Fish Bed Conglomerate" when it turns out that title has been used for at least a couple different layers, namely the base of the Austin Chalk and a phosphatic pebble bed that exists a short ways below the base documented by Taff and Leverett way back in 1893. This mixup has caused some confusion it seems in old academia. Anyways the stratigraphic chart (Fig. 2) in the source below shows these two phosphatic layers and some info on them. I kinda had a mind blown moment as I have actually visited both of these layers while looking for the Basal Atco at a couple of locations. The site where these teeth were found along with all my other written Atco adventures did actually in fact occur in the Atco or earliest Coniacian. However, the "second location" noted in the report I've linked below was actually at this Arcadia Park phosphatic pebble bed. These two layers are quite distinct and my "Atco" site definitely better fits the base. The sea levels paper specifically notes the layer as being ripple bedded which I coincidentally took a picture of in my old report! So satisfying when everything clicks into place... Hancock, Jake M., and Ireneusz Walaszczyk. “Mid-Turonian to Coniacian Changes of Sea Level around Dallas, Texas.” Cretaceous Research 25.4 (2004): 459–471. Web. As a bonus for reading through this, here are a couple of nice sharks teeth I found from the same layer. They are my first larger complete Cretalamna from the location and a new species on top of that. They compare best with Cretalamna ewelli which Siversson notes as being present in the Late Coniacian. I have some less impressive Cretalamna from the location that I previously identified as C. gertericorum, but I may have to double check those since it would be weird for two species to show up on top of one another in my opinion. They are very similar-looking species so I wouldn't be surprised if I was mistaken before. Cretalamna ewelli with beautifully splayed cusplets Looking forward to hearing yall's opinions! Thanks
  10. Jared C

    Pycnodont oral tooth

    From the album: Texas Santonian stage (Cretaceous)

    Pycnodont oral tooth Santonian Austin Chalk
  11. The weather's finally warming up here in DFW, and with that, it's time to move on from the comforts of dry land and return to the ways of creek stomping. These past few months, I've been mostly hanging around cuts and construction sites within the Washita Group, and to be honest, I've gotten a little sick of it. During that period, I steadily accrued a sizable list of potential Eagle Ford and Atco locations within the metroplex, and I was itching for the opportunity to finally go and check them out. Yesterday, I circled a few spots on the map and hit the road. Well, the first couple of sites were more or less complete duds. Stop 1 was situated in the Turner Park Member of the Britton. Lots of cool stuff can be found here and it's one of the more prettier formations, but I'm still trying to figure it out. I only spent about 30 minutes there, and nothing really impressed me. Nevertheless, I was at least rewarded with my first ptychodus from DFW (yeah it took awhile). Stop 2 was a famous site within the Camp Wisdom Member of the Britton. There were some interesting cephalopod specimens to be had, but nothing worth taking home. I did not lose hope, though. I knew that my third site was the most promising of the bunch and I accordingly saved most of the day for it. Stop 1 in the Turner Park, and my first ptychodus from DFW (P. anonymous) The Atco lies just above the Arcadia Park Formation of the Eagle Ford Group in DFW. It's famous for being densely packed with a diverse array of vertebrate material dating to the Coniacian, mostly concentrated within a thin layer dubbed the "Fish Bed Conglomerate" just at the contact of the Eagle Ford and Austin groups. The key to finding this layer is to look for matrix that is highly concentrated in phosphatic pebbles and fossils. Down in Austin, I think it gets a bit overshadowed by the Eagle Ford. In DFW, however, I would say the Atco reigns supreme. After a decent drive and trek, I stepped into the creek and began my descent through the Austin Chalk in search of this coveted conglomerate. It was difficult to tell where exactly I was stratigraphically since the Arcadia Park seems to be a bit calcareous whereas the Austin Chalk can be a bit marly. Where the calcareous marl ends and marly chalk begins is tougher to differentiate in practice, especially for someone less experienced like me. I eventually reached a large gravel bar and decided to pause the walking and have a look for any clues. I didn't find anything out of the ordinary in my initial scan, and almost picked up my backpack to move on. However, I took a moment to take a closer look at what I had first subconsciously written off as concrete. In this chunk of rock, I saw hundreds of tiny rounded phosphatic pebbles. Once my eyes reached the edge of the block, I spotted the unmistakable serrated blade of a Squalicorax falcatus tooth. There was no doubt, this was Atco matrix! The material was noticeably greyer than I had expected. Down in Central TX, the Atco is about as white as the rest of the overlying chalk. With all of the odd bits and bobs intermingling with the grey rock, it really does look like something manmade. I pulled out the rock hammer and began searching the bar for more chunks of fish bed conglomerate. It's amazing the things your eyes can miss when you unknowingly tune things out. There were very obvious shark teeth encased in many of the rocks I had walked by earlier. I collected several larger pieces and sat down to begin extracting teeth. Found my nicest shark vert yet. Unfortunately, it was super fragile and lots of it broke apart in cleaning. My first oddball tooth from the Atco. It has the shape of Cretalamna appendiculata (in the strict sense), but the presence of labial striations pushes me towards a posterior tooth of Cretodus crassidens. It also notably has doubled cusplets on one side. That same tooth post extraction. It broke in half by the time it got home, so I'll be doing a bit of consolidating. Funky little guy. There were some very large slabs of Atco conglomerate washed out atop the gravel bar. I did some hammering to break them into more manageable chunks so I could rinse them in the flowing creek. As I split one of the large slabs in half, I let out an annoyed sigh as I saw a decent Cretalamna appendiculata tooth crumble from the point my hammer had hit the stone. I tried to push that misfortune out of my mind as I perused across the newly exposed surface for any other teeth. I quickly spotted some fine serrations poking out of a chip of matrix that had just come loose. It was a Squalicorax falcatus doing its best chameleon impression. Please don't break please don't break Voila! By far the largest Squalicorax in my ever-growing collection! Florida megs better watch out... My constant hunt for micros at home adequately prepared me to keep an eye out in the field. I was able to spot a couple of Ptychotrygon triangularis oral teeth throughout the day. I also managed to find a mediocre Scapanorhynchus raphiodon and my first decent Ptychodus whipplei! Managed not to lose it in the gravel. Ptychotrygon triangularis Lots of beat up Scapanorhynchus raphiodon that day Ptychodus whipplei. The bits and pieces I have from Austin look like they were crapped off a cliff by a coyote as some Texas fossilers like to say. After getting a nice sunburn, I decided to get up and explore more of the area to perhaps find a source for this matrix. I spotted a little tributary that seemed promising and had a gander. Some outcrops have a beauty that only fossil hunters can truly appreciate... You who are reading this, I know your mouth is watering A little ways farther, the source is found. As I walked up the small feeder creek, I periodically inspected the pieces of fish bed conglomerate that were scattered in the way of the flowing water. One ball of matrix had an unsuspecting appearance, but something about it wouldn't let me leave it alone. There was what initially seemed to be some part of a bivalve erupting from it, but the color and texture gave off enamel vibes. After hammering off some chalk, I still couldn't figure it out. I eventually extracted the entire thing. It was extremely smooth and came to an edge at the top. The surface was mostly bluish gray and semi translucent. It took a second for the cogs in my brain to start working and realize I'd seen something very similar before. @Jared C and I have been recently discussing Hadrodus, and, of course, one of his best discoveries is a large fragment of Hadrodus hewletti of which shares many visual characteristics with the object in my hand. I was excited to realize I was holding the tooth to a gargantuan pycnodont fish. Just after extraction Occlusal view and side pics For scale. Stay tuned for the identity of this monster After this discovery, my stomach growled, signaling it was about time to head back. This was only my first excursion in the Atco of North Texas, and it had already proven to be one to remember. For sure, this will be a site to return to. As I walked along the banks towards my exit, my eyes were still honed in on the ground as is the curse set upon every fossil hunter. I usually don't find anything on my return walks, but I was delighted to see the sheen of black enamel poking out of some Atco chalk just several feet above the fish bed conglomerate. I popped it out and quickly identified it as Ptychodus, though the species I was unsure of. At the moment, I think it is P. atcoensis as it seems to be a good match with a specimen in Hamm's paper on the Atco. It's got radiating ridges and a marginal area similar to some P. anonymous. That paper mentions Meyer (1974) suggested that the taxon could be transitional between P. mortoni and P. anonymous and I certainly understand that reasoning. It's a little beat up, but that's a rare species and a special one. In situ Radiating ridges and concentric ridges in the marginal area as expected for P. atcoensis Once I got home, I began researching more on my fish tooth to try and pin an ID. My initial idea was that it could be a Hadrodus incisor like what Jared had in his collection based on size and coloration alone. Jared was quick to point out that the morphology differed greatly between my tooth and most incisors. This was a valid hole in the argument and I went back to the drawing board. The tooth was most certainly pycnodont in origin, but the world of pycnodonts is much deeper than most people realize. When examining the edge of the tooth I noticed a characteristic I couldn't come up with a name for until I saw it in one of the papers on Hadrodus Jared had shared. "Papilla-like tubercles" were the things lining the edge, and thankfully the author of the paper offhandedly brought up another genus of pycnodont that shared this trait: Acrotemnus. After some searching, I found a recently published paper by Shimada on a newly discovered specimen of Acrotemnus streckeri from Big Bend in the Ernst Member of the Boquillas Formation. And wouldn't ya know it, Hamm stated that the Ernst Member can be correlated with the Atco Formation (though I should mention a discrepancy in that Shimada places the Ernst Member in the Turonian and not the Coniacian which Hamm asserts the Atco + Ernst to be). The Acrotemnus paper had some high quality images of the dentition of the specimen, and I found the most similarity in size and morphology with the prearticular teeth of their fish. The Shimada paper mentioned that most pycnodonts are small, only reaching about 25 cm in size. To people who are unfamiliar with pycnodonts, these teeth may not look all that crazy, being measured only as 1-2 centimeters . However, scaling the body with the size of the dentition shows that Acrotemnus streckeri reached lengths of at least 1 - 1.3 meters, making it some of the largest pycnodonts to exist at the time! This definitely shattered my preconceived notions about pycnodont fish. Already, the Atco has proven to be one of the most interesting formations in North Texas. This site is a bit of a laborious drive for me, but I'm certain many future adventures will be had and many more fascinating discoveries with it. Thanks for reading!
  12. Cyclist

    Ammonite cast?

    I've had this limestone cast (?) on my back porch for a while now. I picked it up on a walk below my house, and thought it different than the various other oddities I pick up from time to time. I was wondering if this was perhaps some sort of ammonite cast. Any thoughts? Thank you.
  13. Mikrogeophagus

    Ptychodus latissimus

    From the album: Austin Chalk

    Ptychodus latissimus, Travis Co. Cretaceous Mar, 2022 Originally found in a gravel deposit. Formation of origin is unknown. It could be due in part to heavy weathering, but the tooth appears to show signs of digestion. Also thank you to @LSCHNELLE for IDing this guy as well as many other teeth!
  14. Cyclist

    Help with I.D. please

    I am hoping to get some opinions on a couple of pieces recently found in a dry lake bed. They were found about a foot apart among a group of smaller fragments in roughly a 20 foot circular area. Their unusual color and texture (for this area) is what drew my attention. I'll attempt to add a few photos. I have more if needed. Location: Austin Chalk - Rock unit Kau - Period Cretaceous - Epoch Gulfian
  15. Apologies for the dramatic title. I thought it sounded cool and stuck with it even though 90 + 80 + 80 is only 250 . Anyways... This past 30 days, I decided to make it a point to check out some new spots. I won't be living in Austin soon, so I thought it would be good to branch out and scout some new locations with potential. I've found lots of creek-worn mosasaur bits and pieces over the past year. I'm ready to find things in situ, and, one day, something articulated. It's a tall order, I know, but I feel like it's the next step and really the ultimate goal I've always had. So, the first step towards this objective was to find locations and, of course, take a look. This is what I saw! Location 1. Austin Chalk: In my usual Ozan stomping grounds, I've come across a variety of fossils ranging from the Eagle Ford to the Ozan itself. Included, was an assortment of spectacular Austin Chalk invertebrates along with the occasional and highly sought-after mosasaur vertebra. They can be readily distinguished from their Ozan counterparts by their yellow-orange preservation and lack of pyritic elements. Honestly, I come across them just as commonly as I do Ozan verts, so I took this to be a sign that the Austin Chalk could be a good bet. In Austin, it's a pretty wide formation with lots of members to look into. I did some research and found a place with some potential. When I arrived, it was a hot afternoon. I picked up my backpack and swapped my school notes out for a rock hammer and a couple of icy bottled waters. Walking down a little trail, I came across the first large exposure of Austin Chalk in what I believe to be the Dessau member. Literally within the first minute, I had to take a double-take at a white glint on the ground. "Surely there couldn't already be a shark tooth," I thought to myself as I kneeled for a closer inspection. Sure enough, it wasn't just a shiny piece of shell; it was indeed the enamel to a bleached tooth from the king shark of the Late Cretaceous seas, the infamous Cretoxyrhina mantelli! Thankfully, it popped out in one piece. A recreation of the tooth in situ and after extraction. I poked around the rest of the surrounding exposure. There were a couple of mangled echinoid bits and gastropods, but not much else, so I continued on to search the main creek. Unfortunately, the only apparent path forward was along a narrow and steeply banked feeder stream. Many of you will know that navigating through these can be a real pain. The brush was densely packed and smelly stagnant water had to be avoided with every step. There were thorny vines dangling from each limb and I was constantly tasked with picking off the burrs that snagged onto my clothing and in my hair. Last year, I was in a similar situation when I was suddenly attacked by a hive of wasps (don't worry, I managed to avoid getting stung too much). It's a fun story to tell friends now, but I must admit that the thought always crawls back into my mind when I am in a position that's a bit difficult to get out of in a hurry. Anyways, after about twenty minutes, I took the final hop over a fallen tree to get to the main creek. It was nice to breathe in the fresh, open air as I sat my backpack down and took a rest, of course, with my eyes perusing along the limestone bed. After the brief sit-down, I began to notice the beauty of the area I was in. The air was filled with the drip-drop of water leaking from the fern-covered bank and the reflection of the greenery was simply mesmerizing. I couldn't help but snap a quick photo. A beautiful, hidden place away from the city. Though, not too far... there's a shopping cart wedged in the gravel just out of frame. In terms of fossils, this place was loaded. Just about everywhere I stepped, I was standing over piles of clams and oysters along with the occasional baculites segment. I didn't bother taking any of these with me, however, as I have plenty already. I noticed there was a decent amount of chert as well, so artifacts were on my radar when I came across a preform. A little farther down the creek, I found a nice ammonite fragment. I didn't intend on keeping it, but sometimes it's nice to have something to hold so I took it along with me. By now, much of the afternoon had come and went. It was about time I turned around and faced the prospect of navigating my way through the dreaded feeder creek in reverse. As I was coming to a stop, I saw a girl walking along the slanted banks of the creek who almost certainly did not enter the way I did. I tried my best to get her attention without spooking her (keep in mind I look and smell like a swamp monster at the moment). She was nice enough to come close to the limestone ledge and introduce herself as I trudged my way through knee deep waters towards dry land. Turns out, she's a local who often hikes by the creek. We chatted for some time and I ended up giving her the preform and ammonite fragment, hopefully inspiring a future hobbyist. After explaining the situation I was in, she laughed and pointed out a trail that led back to the road. When I climbed out and exited the trail sore and tired, I kicked myself. My car was right in front of me. I could have taken this path from the beginning, but instead I took the road never traveled and boy did it make all the difference. Location 2. Ozan Formation: Although many of the mosasaur verts I come across are from the Austin Chalk, a significant portion are still from the good ole Ozan. With that in mind, I took a trip to a creek I usually don't hunt that had a decently-sized exposure. Something in a book tipped me off to this particular site, so I had high hopes. The trip from the road to the waterway wasn't as troublesome as the feeder creek from the week before, but it was still a challenge. I worked my way along the dirt bank to a place I could safely enter the waters when I saw what I was more so wary of. Across the lazy stream was a tent set up along a slope with a clothesline and shopping carts around it. On the initial drive to this spot, I did take notice of the pronounced homeless presence in the area. From the cover of the trees, I took a moment to scope out the tent and the surrounding area. The last thing I wanted was to have an unexpected encounter in a secluded place like this. Luckily, it seemed nobody was home, so I entered the creek, though making sure to have my rock hammer visibly in hand. When I approached the first gravel bar, I was greeted with tons of broken down blocks of Ozan shale and various Austin Chalk fossils. Curious, I started splitting the blocks open to see what the area had to offer. Each one was filled with heart urchin spines and plates! Most were fragmented and all were extremely fragile. Still, I took this to be a good sign. After hours of splitting the loose slabs, I finally found a complete irregular urchin. It's a definite upgrade from the half of one I had found a while back in the Ozan (though that one did have a nice red color). A compressed heart urchin. Looks to be Pliotoxaster/Hemiaster? It may appear round, but it is totally flat! The slab splitting continued with some compressed ammonites and enchodus teeth, but not much more, so it was time to move on to the main event. As I walked the rest of the gravel bar, however, I was forced to once again stop in my tracks. Lying in the mud right in front of me was, by far, the largest mosasaur vertebra I had ever seen in person. It had the preservation of what I assume to be Austin Chalk (of course as soon as I return to the Ozan). The underside of the vert was badly weathered, but it was, nevertheless, far heavier than any others in my collection. Plus, I only need one decent side to show in my picture . Gargantuan mosasaur vertebra. I wonder how long the whole lizard was. Welp, there's really no better motivator than something like that, so I took the short walk to the main exposure. A large expanse of creek bed was Ozan shale ripe for the picking. I got straight to working chiseling out every strange thing just poking out of the ground. Most of them were only oddly shaped pyritic accumulations, I'm guessing originally bivalves and poop. Now and then I would come across a Hamulus squamosus worm tube or piece of fish bone. The bed was a little difficult to see as the lack of recent rain meant that the detritus and algae had yet to be washed away. I didn't find much in the water. Thankfully, the dry parts of the bed were easy to probe. Eventually, I came upon something unmistakably bony. Before I could stop myself to snap a photo, I was already digging. It popped out easily and was instantly apparent of being mosasaur, the very thing I was seeking most. Frantically searching for a continuation of the vertebral column, I spotted what I thought was the head of the next vertebra behind. In my mind, I could see it all right in front of me. The ultimate prize was right there! Just some minor excavating and I'll have done it! Perhaps in theme with fool's gold, I was fooled by the imprint of the very fossil I had just pulled out . I was bummed out for a second, until I had time to realize that this was my first ever mosasaur vert found in situ! Out popped my first in situ mosasaur vert! Cleaned up, it is a real beauty. The color of the cuboidal pyrite outgrowths looks amazing when moved under the light. "Fool's gold" is a real disservice as far as names go. And with that, the sun was already starting to set. The finds of the day. 2 mosies, a flattened echinoid, a Hamulus squamosus tube, an Austin Chalk ammonite, and an Austin Chalk Exogyra tigrina. Location 3. Ozan Formation: After crossing such a major milestone, I had no choice but to head out for the Ozan again once a brief rain had passed. This new location was similar to number 2 in that it was a large expanse of Ozan creek bed. Unfortunately, the route to reach it from the road was a treacherous one. I didn't intend on swimming across a sudden deepening of the creek waters, so I had to search along the steep banks for ways to traverse the barrier. There was somewhat of a flattened trail along a slope with various obstacles that seemed the most doable to me. For the most part, I side-stepped my way across, hugging the dirt and tree limbs to avoid losing balance or putting too much weight on the unstable ground. Now and then, I'd have to cross through a bush that would replenish the population of burrs covering every part of me. By that point, I couldn't have complained too much as things were going relatively smoothly. That is until I made one misstep and had to quickly catch myself by snagging an exposed tree root. Regaining my composure, I heard the rustling and sliding of a plastic bag followed by a loud splash of water from underneath my feet. I usually carry my dirty pair of tennis shoes in a plastic bag since I swap between them and water shoes on my excursions. Now they were just a white shimmer far beyond reach. I hopped off the bank and landed on firm ground. Most of the bed was readily exposed to the air. There was a high density of deer and raccoon tracks. I was entertained most by the shale claw marks I saw at the bottom of shallow pools that I interpreted to be raccoons taking a refreshing swim. From way up the creek, I even caught a glimpse of a coyote jumping from out of the foliage. He sniffed around a bit before noticing me and darted off the other way. I settled down to catch my breath and inspected broken bits of Ozan shale nearby. Pretty soon I spotted the first regular echinoid I've seen in the Ozan. Unfortunately, it was too fragile and didn't survive the journey home. A regular echinoid and a mess of urchin spines surrounding. This portion of the Ozan is rich in echinoid material, though heavily compressed and often very fragile. Denture clams are the other most common find of which fragments can also be seen here. After some rehydration, I got up to start looking for bone. It took some time, but I eventually found a peculiar specimen sticking out of the shallows. It was too suspect to ignore, so I began excavating. Spongey thing as originally found. I was hoping it would be a rib or something, but it just didn't look right. The pores of the cancellous bone were much larger than what I was familiar with for reptiles and the thing didn't seem like fish at all. Typical for fossils in this layer, there was pyrite all over. However, there was an additional mineral I hadn't encountered before. Encrusting the entirety of the underside were selenite(?) crystals in prismatic shapes. As I dug deeper and deeper, the form continued on. The spongey thing was long and had curvature. There was another short one layered just underneath it intersecting close to the hammer. If it's vertebrate, I have no idea what bone it would be. I suspect it's invertebrate in nature. Revealing more of it showed that a separate, shorter piece was present just underneath. Both structures were flattened, fragile, and had to be removed in chunks. From what I could tell, their spongey structure remained consistent across the entirety of their lengths. Once extracted, I searched the surrounding space, but found no sign of continuation. Post extraction I was completely stumped by what I had found. All I could think was spongey, pores, spongey, pores. I am embarrassed to admit it took me way too long to cut off the "y" and realize that it's likely a sponge. Pore bearing (porifera) is about as accurate as you can get when describing it. So, I settled with that as my final guess for what this mystery structure could be. Though, this is still up for debate, so let me know if there are any opposing opinions. From there, I took a couple of paces before stumbling upon the next thing of interest. It was a robust black protrusion with some apparent symmetry. Okay, if the last thing was pseudo-bone, surely this had to be the real thing. As per usual, there was pyritic encrusting on it. From how it was positioned, it was hard to say how long it could be - if there was much more to try and dig out. I got to chiseling and it popped right out within the first few swings. Instantly, I knew I had once again fallen for some pseudo-bone. That being said, it was the first time I had found carbonized wood in the Ozan. I don't usually keep fossil wood, but this guy is interesting enough to warrant it. A pyritized deposit of coal, pretending to be a mosasaur rostral. The fossil wood with a pyritized denture clam and Serratolamna(?) tooth on top. A piece of an artifact and irregular urchin on top. The clam on the right is a cool optical illusion. It's only 3/4 of an inch tall. Here and there I made some other nice smaller finds. A fragment of an artifact, some shark teeth, and an even better flattened irregular urchin to name a few. Though, I had spent a lot of the recent weeks hammering away at things in creeks, so I thought it would be best to call it early and head home to have a nice meal and reflect on my prizes. No articulated mosasaur bits, but a great many lessons learned and special memories to reminisce upon in the future. I know I'm preaching to the choir with this one, but there are few things as magical as traveling alone and exploring a side of the outdoors you hadn't encountered before. It's hard to explain, but I love just parking somewhere and walking into a part of the brush where few people go, if ever. It's freeing in a sense. But for now, I've creek walked way too much. I'm gonna go hunt a roadcut or something
  16. Found this one while on my morning walk creek walk with my dogs. Recent heavy rains, so I'm guessing it washed out of the bank within the last week. It was just sitting on the gravel bar. I have another post with a recent find that the group identified as “Mosasaur indet. cf. Tylosaurus sp.” This tooth felt noticeably heavier than my other find. It weighs 16.1g on my coffee scale. Last pic included of other finds. I'm thinking T. proriger, but am new to this and would love to know more about it. @Jared C @pachy-pleuro-whatnot-odon
  17. Hey y'all! I am a geology/paleontology student at Texas A&M and I am researching the Austin Chalk. I was wondering if anyone had any good Austin localities near the Waco/Temple area or anywhere near 35 all the way up to Dallas. I’ve researched a few old papers and found a couple of spots but I figured this forum could be a good outcrop resource as well. Would love some help! Thanks so much.
  18. I have been hunting the Basal Atco member of the Austin group in Central Texas for about 7 years. Others say that it is the uppermost part of the Eagle Ford. I don't doubt that it is some type of erosional zone involving the two. I have found hundreds of fossils in it. Most of them are beautiful reddish brown color. Most of them have been damaged somewhat by paleo-erosion before they were left in their final state. Many Basal Atco fossils are very interesting to me, because I can't find them anywhere else. My first area to hunt back in 2015 was a lot of fun. An exposed bluff where a giant chunk of the overhanging bedrock limestone had fallen down into the creek. I'm glad I wasn't under that whenever it fell. But, it left behind a nice exposure of what I came to think represented the Basal Atco. Boy was I wrong. Over 100 Ptychodus and other shark's teeth from the same area within a 1 ft thickness of conglomerate like material. Since then I have been at multiple locations of the same Basal Atco with many different expressions of what that might look like from a soft shaley mudstone to a hard rock-like conglomerate to primarily white thin sandy limestone seams with only occasional fossils in the middle of the bedrock. Most of these Basal Atco exposures have no fossils WHATSOEVER! I have found only half again as many Ptychodus fossils in all the other Basal Atco sites combined. Maybe I'd have better luck hunting the gravel banks - which is not my forte. I found a new location that I was not aware of early this summer. It was kind of fun hunting it because it was different than all the rest. I pulled out a partial ammonite and knew that I was in the Basal Atco formation and that there might be more fossils in there. It was obvious that other people had probably been hunting it some before I had been there. I came a second time and walked the football field length of the seam. If you've ever hunted the Basal Atco, then you know you might find yourself under an overhang of a large bluff that could collapse on you at any moment. This one was not that bad! I have generally avoided the areas with the most extreme overhangs. Those where you feel like you have entered a cave-like area (like Mesa Verde) where the rock acts like a huge roof over your head - that (in my overly cautious mind) could fall at any moment. So my goal was to hopefully find a Ptychodus martini. I have developed long-term inflammation in my wrists and hands. So hammering with a big 3 lb hammer or geologic hammer to break open limestone rock is no longer a pleasant thing. In fact, it can be downright debilitating for the next few days. But I did it this one time and was rewarded with a few Ptychodus teeth out of a 7 ft length x 1ft wide triangular seam of sandy limestone. The largest Ptychodus was 18 mm wide and it initially appeared to be what I was seeking. But, upon further evaluation it was instead a nice Ptychodus latissimus. The latter species is perhaps my favorite from the Atco. Under the light it has a little bit of a rainbow sheen which doesn't come out in the photos. I don't know that it has pyrite as part of the preservation. I've seen and found Ptychodus that were completely pyritized from South Dakota and this was not like them. The first photo is initial shot of the Ptychodus latissimus in the rock. The second is of a similar limestone flaggy rock to the one I found these fossils in. The third is a shot of it in my display area partially still in the rock. The final picture is a shot of one found in North Dakota that is a Ptychodus marginalis that was completely pyritized. Mine is a little smaller. The last photo is a side view of the Ptychodus latissimus. It comes out of the rock but still has the root. You can see how low the crown is. My wife and I have continued our monthly fossil forays (her Christmas gift to me) finding at least one nice Ptychodus fossil on each outing. On the above featured hunt, she and one of my adult daughters were at home with a very unkind version of COVID19. So, my wife kindly invited me to "get some fresh air" and leave the house for a while. So I took her up on it and hunted several places on that hot day. Cheers!
  19. For whatever reason, I used to completely dismiss the Austin chalk as a formation of any interest. I viewed it almost through the same lens that I view the Edwards formation, as if it was some barren uninteresting hinderance that gets in the way of cooler formations. Accidentally finding a large Parapuzosia ammonite in it once changed that a bit, but for the most part I still ignored it... Turns out I was just looking in the wrong places, and had very little understanding of its members. @LSCHNELLE recently explained a lot of it better to me, and so equipped with new knowledge I decided to try and discover a member of the Austin Chalk I've been wondering about for a while now, which I always falsely assumed was its own formation. I found myself deep in a Travis county creek, following very specific instructions I had read on an old thesis from the 80's I found online. To avoid being too long winded - nothing stood out to me as different in the geology, so I think that the vertebrate rich member I was seeking still eludes me. Yet, I wouldn't say I was skunked, because I found some very interesting invertebrates that even a simpleton like myself can appreciate My first find had me cheering and jumping, partly because of how just picture perfect the insitu was, but mostly because it was just an aesthetic looking echinoid I haven't seen before. Here it sat below, as I originally saw it: Fortunately, what's left in the matrix I believe is still in great detail. It's just on a smaller-than-it-looks exposed portion where the wear took a toll, as you will see at the end when I show more photos. For another hour and half beyond this, I was just sloshing my way through the water, very slowly, admiring the highly fossiliferous limestone as I went. Usually when I scout a new spot, it ends up being more exploring than actual hunting, and yesterday was no different. Close to my turn around spot, I for whatever reason took strong notice of inconspicuous looking pebble lying loose on its own. Picking it upon a whim, I was surprised to see it was another echinoid of the same type I found earlier, albeit in worse condition. Pictures all at the end. (update: I now know that these are cidarids - funny that on april fools day, I make two of my rarest invertebrate finds, back to back. Odds are I won't have a luckier day in the invertebrate field ever again) Walking back was a serene vibe with few fossils - I was distracted by the new greenery that's been blooming lately. When I got back to where I found the first echinoid, I decided to poke around a bit more, and was surprised to find two ammonites - one large (Mortoniceras?) which I removed, and a much smaller ammonite as well. Results below! No vertebrates but these were well worth it! @JamieLynn put together a phenomenal guide of the inverts by formation that we can find in our central texas stratas, but I wasn't able to find these echinoids in it. I'm aware they need prep, but if you know what they are already please chip in! Results below: Echinoid #1: Echinoid #2 - While it's in worse shape than even the first, I think the substantial attached matrix has protected a lot of it. We'll find out when it preps! Larger ammonite I removed - glue will come to the rescue here. I'm rather sure that the inner coils are preserved under that! Smaller ammonite below: This was just one day sandwiched into what is so far a very busy weekend for me on the paleo front - lots of exploring, and also some good work brewing on two interesting, older vertebrate finds. I'll update this post when i eventually manage to get these echinoids cleaned - the hard limestone they're in will be tough for hand tools - perhaps this is my signal to finally buy a scribe. (update: rest assured, I won't be tackling these echinoids with my rudimentary prep skills - It'll be done by a professional)
  20. For whatever reason, I used to completely dismiss the Austin chalk as a formation of any interest. I viewed it almost through the same lens that I view the Edwards formation, as if it was some barren uninteresting hinderance that gets in the way of cooler formations. Accidentally finding a large Parapuzosia ammonite in it once changed that a bit, but for the most part I still ignored it... Turns out I was just looking in the wrong places, and had very little understanding of its members. @LSCHNELLE recently explained a lot of it better to me, and so equipped with new knowledge I decided to try and discover a member of the Austin Chalk I've been wondering about for a while now, which I always falsely assumed was its own formation. I found myself deep in a Travis county creek, following very specific instructions I had read on an old thesis from the 80's I found online. To avoid being too long winded - nothing stood out to me as different in the geology, so I think that the vertebrate rich member I was seeking still eludes me. Yet, I wouldn't say I was skunked, because I found some very interesting invertebrates that even a simpleton like myself can appreciate My first find had me cheering and jumping, partly because of how just picture perfect the insitu was, but mostly because it was just an aesthetic looking echinoid I haven't seen before. Here it sat below, as I originally saw it: Fortunately, what's left in the matrix I believe is still in great detail. It's just on a smaller-than-it-looks exposed portion where the wear took a toll, as you will see at the end when I show more photos. For another hour and half beyond this, I was just sloshing my way through the water, very slowly, admiring the highly fossiliferous limestone as I went. Usually when I scout a new spot, it ends up being more exploring than actual hunting, and yesterday was no different. Close to my turn around spot, I for whatever reason took strong notice of inconspicuous looking pebble lying loose on its own. Picking it upon a whim, I was surprised to see it was another echinoid of the same type I found earlier, albeit in worse condition. Pictures all at the end. Walking back was a serene vibe with few fossils - I was distracted by the new greenery that's been blooming lately. When I got back to where I found the first echinoid, I decided to poke around a bit more, and was surprised to find two ammonites - one large (Mortoniceras?) which I removed, and a much smaller ammonite as well. Results below! No vertebrates but these were well worth it! @JamieLynn put together a phenomenal guide of the inverts by formation that we can find in our central texas stratas, but I wasn't able to find these echinoids in it. I'm aware they need prep, but if you know what they are already please chip in! Results below: Echinoid #1: Echinoid #2 - While it's in worse shape than even the first, I think the substantial attached matrix has protected a lot of it. We'll find out when it preps! Larger ammonite I removed - glue will come to the rescue here. I'm rather sure that the inner coils are preserved under that! Smaller ammonite below: This was just one day sandwiched into what is so far a very busy weekend for me on the paleo front - lots of exploring, and also some good work brewing on two interesting, older vertebrate finds. I'll update this post when i eventually manage to get these echinoids cleaned - the hard limestone they're in will be tough for hand tools - perhaps this is my signal to finally buy a scribe
  21. Mikrogeophagus

    4 Mosasaur Verts in a Day! Austin TX

    With the end of the semester approaching, school has picked up and I have been too busy to embark on many adventures. When my schedule finally cleared up one afternoon following a brief rain in Austin, I jumped at the opportunity to do a bit of exploring. One of my goals right now is to check out new parts of the creek I hunt on. Scanning through my list of potential spots, I decided to try and be the first one out to a very promising location. Like my previous hunts, this place ran through the Ozan formation, so my expectations were set on some nice Cretaceous specimens as well as the usual native artifacts that Central Texas is so famous for. After I parked and carefully scaled my way down to the water's edge, I was immediately met with several pairs of shoes and jackets. Thinking I had been beaten to the punch, I decided I might as well head down the stream and meet whoever it was to discuss the location and fossils in general. Thankfully, the trip was saved when they turned out to be a kind group of fishermen. After a brief chat, I carried on to get the hunt started. The mud was an absolute nightmare. I had never been up to my knees in it until then. Somehow, I managed to trudge my way through without getting one of my water shoes sucked away into a different dimension. When I finally reached the first gravel bar, I was instantly rewarded with the nicest Ptychodus tooth (E) I have found yet. Scattered around the bar were tons of flakes and a couple of larger worked pieces (G, I) that were unfamiliar to me. Before moving on, I also stumbled upon what would've been the largest point I'd ever found (H). Unfortunately, it was pretty banged up. The previous rain wasn't that big in terms of flooding, so I spent the most time scouring the gravel still under water as I reasoned that the stuff on dry land was less likely to have been moved around in the storm. It was during this moment that I found my first mosasaur vertebra of the day (A). This one was exciting to me as I personally thought it very much resembled the verts that famously come out of the NSR's Ozan formation. Within a couple feet of it I found another half piece of mosasaur vertebra (B). With the close association of these two bones, I went into a bit of a frenzy. Nothing else came up, but I knew that there was a massive exposure just up ahead so I hurried on. Along the way I ran into a fragment of the smallest point I've come across (F). At its size, I wonder if the original piece would've been a true arrowhead. Once I reached the main exposure, I immediately got to probing around. I came across two more pieces of bone that I believe are both belonging to mosasaurs (C, D). They have bony structures, but they are also pretty beat up and may have come from a different formation in comparison to the other two verts I collected. With the day winding down I picked up a nice big Exogyra ponderosa for my dad's friend as well as a couple of preforms. I tried to look around in the exposure for any hints of mosasaur, but that shale is extremely difficult to get through. All in all, it was a great success. I think I've found my new go-to spot! With the addition of potentially 4 new mosasaur verts, that's a 400% increase in my total mosi collection! P.S. Does anyone else get "Tetris Syndrome" after scanning gravel bars for way too long? For hours after the trip, I literally could not stop seeing gravel and chert flakes every time I closed my eyes. An overview of the finds: Closeups for ID: A: First mosasaur vert of the day. To me, it strongly resembles those found in the NSR's Ozan formation. This one was covered in a clay-like matrix. B: The second vert of the day. Seems to be broken in half and from the same formation as A. Appears to have pyritization on some parts of it. C: Third vert which I believe is mosasaur. This one is beat up and seems to be of differing material from A and B. Could it be from the Austin Chalk which is present farther up the creek? D: The last "vert" of the day. This one I am least confident about. It appears to have a bony texture, but is very worn and has a confusing shape. It seems closer to C than A or B, but it also feels very distinct in it of itself. What do you guys think? I suppose it could be something else entirely! E: A nicely preserved Ptychodus tooth. I'm thinking anonymous or mammillaris, but my ID skills are pretty lackluster. F: "True" arrowhead fragment? G: Strange artifact. The angle seems too wide to be a point. I think it's too thin to be an adze. Obviously missing a huge chunk from that fresh curved break. What do you guys think? H: Fragment of a large point I: Another strange fragment. I think it may be an adze since it's a bit more robust. Fresh break on one edge. Let me know if you want any more close-ups. Thanks for reading!
  22. roxanneminerals

    Austin Chalk Mosasaur Fossil ??

    I found this rock in Austin, TX in Waller Creek next to an exposed outcrop of the Maastrichtian (Late Cretaceous) Austin Chalk. I’m wondering if it’s a mosasaur vertebra or humerus? Several mosasaurs have been found in creeks nearby, and the wavy pattern in the rock reminds me of fossilized bone. I’ve included three photos of the rock that I found in Austin, and a photo from Otero et al. (2016) of a Maastrichtian mosasaur right humerus (scale bar = 50 mm) that looks similar.
  23. Creek - Don

    Just a rock or something else?

    Can anybody ID what this is? I found this several years ago in the North Texas creeks. It has some spots on the top and broken shells mixed with it. Could that round dark spots be coral or bryozoans?
  24. ThePhysicist

    Pycnodonte in situ (4)

    From the album: Austin Chalk

    Pycnodonte aucella, oysters abundant in the chalk.
  25. ThePhysicist

    Inoceramid in situ

    From the album: Austin Chalk

    Inoceramids were very large clams that are abundant in the chalk. Often you only find portions like this, with telltale calcite prisms (seen here as vertical lines) which composed their shells.
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