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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!

Late last year I received some micro matrix from @Notidanodon that he collected from the Isle of Wright (UK) out of the Greensand Fm. near Yaverland. This material is Lower Cretaceous, Albian aged. I have picked through much of it and have some questions on what I have found. I am not well versed in the fauna from this area and some internet searching has led me to some suggestions, but I'm hoping Will or some of our more experienced collectors from this area such as @Welsh Wizard, @Yoda, @Bobby Rico, and any others that I cant think of off the top of my head, can set me straight. #1. One of the more common (relative term) items I found were these small teeth that belong to some Chondrichthyian, but I am not sure which one. My first guess, based on what little bit I'm familiar with, was some sort of Sclerorhynchidae but I had some doubts due to a total absence of a root on these, then I saw some Hybodontidae (Lonchidion/Lissodus) were found in this formation and some looked similar but not exactly the same, and then otheers reminded me of some Rajiformes with the small lingual face that you can see on some of them. So here I am. They were relatively common so I'm sure someone will recognize them right off, even if the pictures are not ideal. These are about 2-4 mm at their widest. There could be several different types in here, so if you can just get me started with a genus or group, or want close-ups of a particular one, just let me know. #2. Next up are a bunch of shark teeth partials, most are probably too worn or fragmentary to ID, so that's OK. I just wanted to show what else was in the sample. Again, total width of the container is 2cm, so these are all less than 4mm. #3. I believe these to be a fish scale and found many references to Lepidotes, now known as Sheenstia, from this section and they look somewhat similar, so I just would like to confirm that. The largest one has a max. dimension of just under 5mm. #4. These are some other small teeth that may of may not be identifiable. 2-3mm #5. Next up is a small jaw fragment. I know it needs cleaned up some more, but it is somewhat fragile and I didn't want to poke at it too much just yet. Is this fish, something else, or impossible to say? Length is about 4mm. #6. And finally, some fish vertebrae. Again, no ID requested, just wanted to show what else was in the mix. I know reptiles and amphibians are found in this formation, I'm not sure I'm qualified to try and separate those out, especially since may of these are highly phosphatized (is that a word?). Thanks for looking and for any advice that can be offered. And thanks again to Will, for the interesting matrix. Mike

On the night September 2, 2018, a large fire ripped through the prestigious National Museum of Brazil. By the time it was put out, a plethora of precious artifacts, including many dinosaurs fossils (with still many to this day missing). Of the specimens currently missing since the fire - the Holotype of a small theropod dinosaur from the Albian Cretaceous of Brazil's Santana Formation named Santanaraptor placidus. Santanaraptor (Romualdo Member of the Santana Formation) (Early Albian, Cretaceous period 112.6-109.0 million years ago) Specimen: MN 4802-V (partial skeleton with preserved soft tissue) http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=67712 What makes this dinosaur special is, according to recent studies from the 2010s, it is one of the only known Tyrannosauroidea dinosaurs from South America (along possibly with Mirischia). (Also, thanks @Troodon for letting me know about this phylogenetic chart) Source of info and chart: https://www.sciencedirect.com/science/article/abs/pii/S0031018218302566?via%3Dihub The paleontological significance of this specimen cannot be understated, but there is some hope the specimen survived the tragic fire (possibly in one of the museum's metal shelves). https://www.nature.com/articles/d41586-018-06192-9 It's been between 4 years since the fire and the specimen whereabouts are still unknown. Does anyone (ANYONE) know if the Santanaraptor specimen MN 4802-V survived the fire at the National Museum of Brazil and if the specimen is now safe?

The brief visit to the second half of the Pawpaw exposure turned out to be a huge success. I didn't think it was possible, but the finds got even better! There wasn't much of a story to be had with accessing the site, so I'll keep things brief and jump straight into the finds. Once I relocated the productive greyish layer, I was already gathering various claw bits left and right. Their bright white coloration really makes them pop out from the ground. However, I didn't let this lead me into lowering the thoroughness of my search. I still took a close look at every pebble and under every rock. The fruit of my labors came when I locked onto the first shark tooth for the site, a small Leptostyrax macrorhiza. I've found one in the past in the Duck Creek, but never in the Pawpaw. Nine times out of ten I would have missed this guy. Just look at how hidden he is in this photo: Leptostyrax macrorhiza hidden beneath a couple pebbles The vertebrate finds continued with a tiny ~1 cm fish jaw fragment. Let me know if you recognize it: Close up with my new stereo microscope! Not too long after, the crustacean finds began to ramp up. Scattered about were fragments of carapaces. It was only a matter of time before the first complete carapace of the day was found. Steorrosia aspera I want to say I continued finding several more that weren't impressive in situ, but amazing after cleaning. One Steorrosia sp. was pretty banged up on the sides, so I couldn't confidently pin an ID. However, I noticed that it had little black dots where the eyes are usually missing in these crab fossils. Well, my Christmas gift came right on time! I placed it under the digital microscope and almost fell out of my chair. This little crab had preserved compound eyes. I'm not sure how rare such a feature is, but it impressed the hell out of me. I should warn that the pics aren't terribly clear since taking photos requires me to press a button on the microscope that shakes the whole thing. Plus, viewing something so small had the device at its absolute maximum magnification. Hopefully you all can spot the pattern on the compound eyes. Underside of the Steorrosia sp. The face of the Steorrosia sp. A close up of one compound eye. Those faint circles are what I interpret to be the individual eyes. Although not from the grey layer I was hunting in, pyritic cephalopods could be found washed out from the red sandstone above. Most are pretty beat up, but I make sure to collect a little bit of each species I can find. I have enough Engonoceras serpintinum as it stands, but I can't help taking a picture when I find a nice one. Engonoceras serpintinum Mantelliceras sp. The first unorthodox find of the day was very clearly a tiny brittle sea star leg. I've always wanted to find starfish parts, so I was super excited to pick this specimen up.... little did I know. Not sure if it possible to ID beyond genus from just a leg segment: Ophiura sp. in situ Close up of same leg From there, I found a couple more very nice carapaces including a MUCH more complete Texicancer renfroae?. Face of the Texicancer renfroae? I hate to say I may have already found a Feldmannia wintoni that surpasses the one I submitted to FotM I need to figure out how to turn off that pesky time stamp on the bottom right. Starting to feel like I'm taking crab mugshots When I got home, I was able to clean up and analyze a couple of enigmatic specimens that had initially given me starfish vibes. After a bit of research, I believe my hunch was right. These two specimens each have one side covered in "spikes". I found a paper (Blake and Reid 1998) on Pawpaw starfish that had similar structures on the oral sides of the arms. Betelgeusia reidi (cool genus name btw) seemed the closest match, but it's a tough call. And to round it off with one of the most legendary finds in my fossil hunting career, a mess of associated brittle sea star chunks including the central disc and several arms fragments. I tried to find more, but these were the only pieces I came up with. It was a massive pain paraloiding this thing together I must admit. There's not much surface area to work with, but it eventually came it alright. Actually looking at it again, I think I put the short arm on upside down, but that will be a headache for another day... The only local brittle star species I know from this period would be Ophiura graysonensis and O. texana. Hard for me to say which it resembles more closely, but I'm leaning towards graysonensis, assuming those exist beyond just the Grayson Marl. The central disc and a couple of arm bits in situ Oral side? Aboral side? It's safe to say this is my most productive hunt yet! Hopefully you all enjoyed reading through this little report. Here is an overview of the finds: Fish jaw section, Leptostyrax macrorhiza, and xiphactinus? tooth fragment (was hoping it was pterosaur ) Crabs of the day L to R: Various Steorrosia, Feldmannia wintoni, Texicancer renfroae?, and Steorrosia reidi? Top: Engonoceras serpintinum Bottom L to R: Mantelliceras sp., Mariella worthensis, Scaphites hilli, and Baculites comanchesnis? Ophiura sp. arm fragment, chunks of Betegeusia reidi?, and a couple of bivalves Thanks for reading!

Hi TFF, Last week the GF and I went for the holy trio (geological wise ), the turonian, cenomanian and albian. It's simply amazing that in a relatively short stretch of cliffs you can find all three. Driving our way there it seemed like the UK also had some decent weather that day as it was quite visible. We first hit the turonian. On the way there you can find santonian(?) deposits which produce some nice flint urchins. I'm usually looking for big ammonites like lewesiceras or mammites. Only two small examples were found that we did not take home. In-situ weathered lewesiceras. For the good eyes amongst us, an i-situ mammites nodosoides. Unfortunately a very flat compressed example At some point a nautilus 'belly' poked out, fairly uncommon and a pleasant find. I believe it's eutrephoceras. Not much later I made a little squeak. We don't find these often here. Meanwhile the GF was very pleased finding another nautilus. Albian deposits drift off towards cenomanian and turonian plates. The next day we were welcomed with a nice rainbow. You see why they call it the 'white nose / blanc-nez'. These visible layers are cenomanian. I hoped for the gault layers (which would be on the other side of the picture) but only some ex situ albian layers were exposed. These are full of pyrite and little ammonites (anahoplites). Sometimes bigger pyrite specimens can be found like this partial beudanticeras. To my surprise something else was just waiting to be picked up. Pretty rare and well sought after. Surrounded by pyrite and ammonites. On the way back we managed to pick up a little acanthoceras. And a final picture

Last weekend was an extended weekend and good weather forecast, that means a few field trips to the French coast for us The first trip was Friday, we got there early in the morning and planned to hunt the Turonian part of the coast. There was a lot of sand on the beaches so we didn’t find much, but quality is better than quantity and Natalie scored 2! Ptychodus teeth. I only found an ammonite that proved to be incomplete after extracting it :/ and a flint echinoid on the way back to the car. On Monday we tried our luck in the Cenomanian and Albian part of the site. Again lots of sand covering op the boulders but we did find a bit more and some really interesting specimens. The 1st interesting piece was a belemnite in the chalk, this might seen strange, but although the belemnites are common in the Albian gault clay, they are almost non-existent in the Cenomanian chalk and it was the 1st specimen I ever found in there. Not long after that It was Natalie’s turn, she found a complete irregular echinoid. The rest of the finds that day were mostly chalk ammonites, except on one spot were a little bit of gault clay was exposed on the beach were we found a nice little phosphate crab. 1st fieldtrip on Friday, early at the beach: little ptychodus 1: Ptychopdus 2: To bad for this one: A flint echinoid on our way back: Field trip on Moday: Belemnite : Neohibolites ultimus Natalie's echinoid: Tiaromma michelini The little crab in situ in the clay peeking out: All the stuff cleaned up:

Hi TFF, The other week I went for a quick trip to the beloved chalk at Cap Blanc-Nez in France. I heard that the gault clay (albian) was exposed, since that's my main interest I had to go and see. 'Sadly' it was layer P6 (late albian) which does not provide as much ammonites as earlier layers. In my experience this layer provides quite a lot of fish remains like teeth and small vertebra. Picked up a small lamniform shark tooth. Besides a lot of bivalves (inoceramus) and gasteropods (gyrodes gaultina) there was nothing but that tooth I took home. Next time I'll make some in-situ photo's because there's tons and tons of phosphate fossils. Probably very similiar to the gault in Folkestone. On my way to the turonian there was a micraster waiting to be freed. Spotted some sutures that fooled me. I thought they went inwards to the matrix but it turned out just to be a chunk as can be seen (sutures going outwards). Rookie mistake hehe. You can also see where the living chamber starts. That's usually a weak spot to be careful for when extracting, in this case there's already a good crack forming. From not to hot, beautiful mammites nodosoides (turonian) just waiting for someone

I picked up the shark tooth below a while back, labeled as Cretalamna borealis. I'm not very familiar with the species--does this ID appear to be correct? The label that came with the tooth says it was found near Stary Oskol, Belgograd Oblast, Russia, and that it's Upper Albian in age from the Kursk Osteolite member of the Seversk Sandstone formation. The tooth measures 38.6 mm along the slant. One of the root corners is missing and there's some hard matrix still cemented to the tooth near the root margin of the lingual side. @ThePhysicist, I think this one might be a Dwardius woodwardi or Dwardius sp., but I'm not sure.

Hi guys anyone recognise this Ammonite from Tulear Madagascar? It’s Albian

My first Metengonoceras dumbli ammonite at the Walnut formation. Although not complete, I've been searching this species of ammonite for many years. Plenty of Oxy's, but never ever found this one. This one measures around 4.5 inches / 114.3 mm.

I'm visiting family in San Antonio, Texas, and have been doing a little fossil hunting as well, including in a nearby creek. Based on a local geologic map, I believe this creek mostly exposes the Edwards Group (Albian age), though there appear to be some younger (Cenomanian age) rocks from the Del Rio Formation mixed in as well, based on an Ilymatogyra arietina shell that I found a couple of days ago. This creek isn't very fossiliferous. In about 3 hours of searching, I've only found a single I. arietina and a few small shell impressions in rocks. However, today, I also found the rock below and am wondering if it's something more. I am moderately confident that the bit in the lower right is a shell impression. What I'm unsure of is whether there's a bigger (worn) shell mold here too or just a bit of pareidolia. Any thoughts? Here's the outline of what I'm seeing -- the dimensions of what I've outlined are approximately 7cm wide x 6cm tall. Here's further detail of the part in the lower right that I'm more confident is part of a fossil shell/shell impression: The "shell mold" is raised relative to the surrounding rock, though is pretty heavily eroded if it is a fossil: Here as well is the I. arietina I found -- no doubt that this one's a fossil at least! And here's a wider shot of the creek: Thanks for looking!