Search the Community

I am not sure if this is the right place to post this on the forum, but I am going to be completely honest and admit that I need advice on trying to get this fossil out in one piece. I have a small portable rock saw which I have tried using to no avail. I have also tried chiseling around it but I am an amateur and have only used this rock saw on easier-to-get targets. I do not want to break this and glue it back together unless it is absolutely necessary. My original plan was to cut in a sort of # pattern and chisel the sides till I got deep enough to chisel out a rectangular slab but then got cold feet. This fin spine is lodged in a half-sunken 5 to 7-inch thick chunk of limestone that is too large to carry or move. I want to try and extract this fossil before the rock pile gets taken to the dump, or this fossil erodes completely into nothing. I know it's not in the best shape but it means a lot to me as it was my first "big find" when I started field collecting a few years ago and any advice is appreciated. I am not sure if I should just keep chiseling the sawed portions till it begins to break loose or what my next steps should be. It is also so close to being covered in sediment and so close to another chunk of limestone I am unable to fit the portable saw blade completely in place to saw more for the bottom portion, beyond where it is already cut. (it is at an incline and the rocks form a sort of V shape). Image taken before sawing began (I am leaning on the other rock): Where I am at: Edit: I think I need to keep chiseling it, but I wanted to consult the experts before I continue further. I think i may have panicked when I heard that the landowner may be calling waste management in a few months. Once again sorry if this is the wrong place to post this, and move this post if need be.

The Ctenacanthiform Sharks are perhaps one of the most famous, yet enigmatic groups of sharks currently known, with a fossil range stretching from the Early Devonian to the Early Cretaceous periods 407.6-136.4 Million Years ago and with a range that spans globally. The most enigmatic along with the most famous genus of Ctenacanthiform (as well as one of my personal favorites) is the genus Saivodus, which was only described properly in 2006 after its fossilized remains were mistaken for two centuries as remains of species belonging to two other Ctenacanthiform genus, Ctenacanthus and Cladodus. The genus Saivodus emerged during the Early Carboniferous 360.7-345.3 Million Years ago and included the largest currently known species of Ctenacanthiformes, the Carboniferous Saivodus striatus that grew up to 35 feet in length fully grown. Despite large numbers of teeth and even very well preserved fossilized remains of the head including jaws and fins from large Saivodus striatus specimens being discovered and described, still very little is known about the overall paleoecology of these enigmatic sharks. Artist reconstruction of an Adult Saivodus striatus and its size compared to an adult Human and adult Great White Shark (Carcharodon carcharias) by artist HodariNundu. Image Source: https://www.deviantart.com/hodarinundu/art/Super-Sized-Saivodus-866628428 https://paleobiodb.org/classic/basicCollectionSearch?collection_no=84108&is_real_user=1 The latest record of the genus Saivodus was believed for a few years to be fossils of a small Saivodus sp. from the Fossil Mountain Member of the Kaibab Formation dating to the Kungurian stage of the Permian period 279.3-272.3 Million Years ago in what is now Kachina Village of the U.S. State of Arizona. Hodnett, J. P. M., Elliott, D. K., Olson, T. J., & Wittke J. H. Ctenacanthiform sharks from the Permian Kaibab Formation, northern Arizona. Historical Biology, (2012). 24. 381-395. Retrieved December 16, 2023, from https://www.researchgate.net/publication/254237970_Ctenacanthiform_sharks_from_the_Permian_Kaibab_Formation_northern_Arizona https://paleobiodb.org/classic/basicCollectionSearch?collection_no=132088&is_real_user=1 However, I just found a confirmed (until recently overlooked) record of the genus Saivodus with the assistance of a recent well researched paper on Ctenacanthiform diversity that extends the geological range of genus by around 25.1-20.1 Million Years. I think you’ll all find this record extremely interesting!!! A Ctenacanthiform tooth were found in 1970 in deposits of the Zewan Formation dating to the Changhsingian stage of the Permian period 254.2-252.2 Million Years ago in what is Guryul Ravine of the region of Kashmir, a disputed territory located at the northernmost point of the Indian Subcontinent of South Asia). This tooth were initially described in 1971 by Paleontologists from Kyoto University, Japan as belonging to a new species of Ctenacanthus, (Ctenacanthus ishii). The size of the tooth is the following: Length of the base of tooth specimen - 16 mm. (1.60 cm.) Width of of the tooth's base - 6 mm. (0.60 cm.) Length/height of each of the tooth's two largest subsidiary or lateral cusps on each side of the tooth - 3.5 mm. (0.35 cm.) Length/height from the base of the tooth's apex to the top of the tooth's central/medial cusp - 8 mm. (0.80 cm.) Photographs of the Kashmir Saivodus sp. tooth specimen from the Permian-Triassic Zewan Formation, Kashmir, Asia. Image Source: https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/186572/1/mfskugm 038001_163.pdf However, further analysis of the Kashmir specimen in 2021 (including the general tooth shape and morphology) has confirmed the Kashmir tooth is in fact the latest geological record of the Saivodus genus currently known. Kapoor, H. M,, and Sahni, A. A Shark Tooth from Zewan Series of Guryul Ravine, Kashmir. Memoirs of the Faculty of Science, Kyoto University. Series of Geology and Mineralogy, (1971). 38(1), 163-166. Retrieved December 16, 2023, from https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/186572/1/mfskugm 038001_163.pdf Shah, I. K., Farooq, M., Meraj, G., et al. Geological treasure of Guryul ravine section in Kashmir Himalaya - a case report. ESS Open Archive. (2022). https://doi.org/10.1002/essoar.10510303.1 https://d197for5662m48.cloudfront.net/documents/publicationstatus/75277/preprint_pdf/7673ce9d023bd875199a50b14e3f42e7.pdf Feichtinger, I., Ivanov, A. O., Winkler, V., Dojen, C., Kindlimann, R., Kriwet, J., Pfaff, C., Schraut, G., & Stumpf, S. Scarce ctenacanthiform sharks from the Mississippian of austria with an analysis of carboniferous elasmobranch diversity in response to climatic and environmental changes. Journal of Vertebrate Paleontology, (2021). 41(2). https://doi.org/10.1080/02724634.2021.1925902 Not only does this expand the geologic range of Saivodus and is the first confirmed record of this genus from Asia, but the proximity the Kashmir specimen was collected to the location of the Permian-Triassic boundary at the Zewan Formation (only 3 meters away from the geologic boundary) could indicate small to medium species of the genus Saivodus survived the Permian-Triassic Extinction Event 252 Million Years ago and survived (albeit very briefly) into the Early Triassic. This is a major discovery in the study of Ctenacanthiform sharks. Hopefully more specimens of Ctenacanthiform sharks from Permian-Triassic deposits in Kashmir, Pakistan, India, and around the world could be uncovered, studied, and described soon so that we may all get a more accurate understanding of the paleobiology and paleoecology of these amazing prehistoric sharks. This will also give us a more accurate understanding of the fascinating time they lived before one of Earth’s largest mass extinction events along with the period of biological and ecosystem recovery afterwards.

Sometimes it could be accurately said a fossil hunting trips most intriguing finds are discovered after bringing the fossils home. That's exactly what happened after my Sunday/August/19/2023 trip with @Tales From the Shale at some Late Pennsylvanian rock formations in Illinois. Lots of brachiopod, bryozoan, and pretty awesome Chondricthyan teeth were found on this trip. But it was at home that I accidentally uncovered a pretty remarkable find I would like help getting a Proper ID for. On Wednesday around 10:00PM EST, I decided to break open with a pretty large hammer some of the large rocks I collected to get rid of excess materials around the fossils. When I got to a brachiopod encrusted rock, I decided to split it down the middle to avoid damaging the top. As a precaution (which I'm super grateful now I still do) I always check the fragments with a flashlight to see if I missed something. This time, I checked extra hard and discovered a very fragmentary cladodont tooth tip!!! I was glad I found it, but kinda kicking myself knowing I may have accidentally smashed to bits the rest of the tooth (the tooth was not even remotely visible on the rock's surface and was hidden in the middle of the rock itself). Fortunately, I searched the surrounding fragments and found the rest of the tooth! I looked at and measured the cladodont tooth fragments more the next morning!! The tooth specimen is definitely from a pretty large Ctenacanthiform Shark! I think (based on the number of lateral cusps) it could be from a large Gilkmanius, but I'm not 100% sure!! What do you guys think? @connorp @deutscheben @Tales From the Shale What do you think?

On Sunday/August/19/2023, myself and @Tales From the Shale went fossil hunting at some Late Pennsylvanian rock formations in Illinois! It was a pretty productive trip! We found lots of brachiopod fossils and an awesome amount of Chondrichthyian fossils! There are some fossils though that I'm a bit confused on their exact ID and I would like help identifying them? I put and photographed some of these specimens under a microscope and dissecting scope to help with species/genera identification. Here are the various and pretty awesome specimens from the trip I would like help Identifying: Unknown Specimen 1 (A Posible and partial Ctenacanthiform tooth) Unknown Specimen 2 (A Peripristis tooth but not 100% sure of exact species ID) Unknown specimen 3 (I think either Deltodus or another type of Petalodontid) Unknown specimen 4 (@Tales From the Shale helped me identify it as a bryozoan, but I forgot what type/genera he said it was (though he said it was pretty rare), I found at least 2 specimens of this type on this trip) Unknown Specimen 5 (Found on the same piece of matrix rock as Unknown Specimen 4, I'm not 100% sure what it is) Unknown Specimen 6 (some other type of bryozoan, I have no idea what could be it's exact ID) Unknown Specimen 7 (Found on the same piece of matrix rock as Unknown Specimen 6, some other type of bryozoan but I have no idea what could be it's exact ID) Unknown Specimen 8 (some other type of bryozoan, I have no idea what could be it's exact ID) Unknown Specimen 9 (A Possible small Petalodus tooth) Unknown Specimen 10 (A Possible small Deltodus tooth)

The Ctenacanthiforms sharks emerged in the Late Devonian period and were one of the earliest evolutionary radiations in the Chondrichthyan lineage. They were also an incredibly successful group, surviving up to at least the Early Cretaceous in deep waters of what is now Southern France and Austria. Image of Reconstructions by J.P. Hodnett of some Ctenacanthid Sharks (the three yellow sharks) from Permian formations at Yellowstone and Grand Teton National Parks, U.S. Image Source: https://www.nps.gov/articles/000/fossil-inventories-uncover-permian-sharks-in-western-national-parks.htm Unfortunately, this group is currently still relatively rarely studied by large sections of academia specializing in prehistoric sharks. This is the case even for species with preserved body fossils such as the magnificent, awe inspiring, and a personal favorite of mine, Saivodus striatus (Duffin and Glinter, 2006)! Duffin, C. J., & Ginter, M. (2006). Comments on the Selachian genus Cladodus Agassiz, 1843. Journal of Vertebrate Paleontology, 26(2), 253–266. https://doi.org/10.1671/0272-4634(2006)26[253:cotsgc]2.0.co;2 However, one incredible genus that deserves more study and academic along with public spotlight is Amelacanthus (Maisey, 1982)!! Maisey, J. G. (1982). Studies on the Paleozoic selachian genus Ctenacanthus Agassiz. No. 2, Bythiacanthus St. John and Worthen, Amelacanthus, new genus, Eunemacanthus St. John and Worthen, Sphenacanthus Agassiz, and Wodnika Münster. American Museum novitates; no. 2722. https://digitallibrary.amnh.org/handle/2246/3536

I am really excited about a project we have been working on. We decided to switch our shark displays from the ones based on Geological era to a taxonomic display style. We had been considering this since we made a similar switch with our dinosaurs. It has made those programs flow more easily and i think allowed the kids to get a better understanding of the animals. We originally set our displays up as they were because we simply did not have enough material to do taxonomic displays. There were a few orders of sharks for which we had only one or two fossils and one extinct order for which we had zero fossils. Doing the displays along a timeline allowed us to cover up the holes in the collection. We have made a lot of improvements to our shark collection in the last year and were strongly considering changing things. A conversation with @siteseer really sealed the deal. Jess nudged me over the ledge lol So work has begun on this project and I am loving it but it is a lot of work. Each order of shark, extant and extinct, will eventually have it's own display. Within the the display, each family or in some cases genus, will be set up by temporal range. I think these displays will not only allow more efficient presentations but will also show temporal range and distribution as best we can. Step 1 was identifying which orders, families, and genera we need to add to the collection in order to round out what we already had. Some orders needed little attention but there were some that needed a bit of a boost. Heterodontiformes was an example of one that needed to a boost. We had Jurassic teeth (Paracestracion and Heterodontus) but little else. Having the Jurassic teeth is awesome because it shows how far back they go in the fossils record but that would be an underwhelming display visually and not give the kids a great sense of the sharks. We had to find fossils to place them at various points in their temporal range and widen their distribution to the best of our ability. Pristiophoriformes was another that we needed to upgrade as we only had one small rostal tooth. We had a good variety of material for most extinct orders but wanted a Carboniferous Xencanthid tooth to better tell the whole story of the Eel sharks as all of ours were Permian. We picked through micro fossils to add Devonian Ctenacanthiformes teeth to expand the temporal range and add diversity in the form of Phoebodus. Step 2 is on going and is probably the hardest part, acquiring the fossils we need. It is quite easy to find some of the things we needed. Others have been extremely difficult and a few are pretty much impossible. We are unlikely to knock Hemiscyllium or Oxynotus off the list. It proved very difficult, but not impossible, to locate a Cenozoic Chiloscyllium tooth. We had Cretaceous teeth but nothing beyond that and Bamboo Sharks are one that we do talk about quite a bit. After a lengthy search, we finally tracked one down and it was quite inexpensive. Cost is always a factor for us so early on we understood we were not going to be adding some collector type teeth like a 2" Chilean White Shark or the transitional White Shark teeth. We focused instead in smaller teeth and anything that added a new shark, contributed to showing distribution or temporal range. For us a STH Scyliorhinus is a significant fossils because it adds to both distribution and temporal range of a shark we talk about. I am very proud of some of the inexpensive teeth we have found including a Chilean Angelshark, a Miocene Mitsukurina, the Paleocene Chiloscyllium, and a Heterodontus fin spine from STH. We have also been greatly aided in our quest by a couple of donations, including one from @Troodon that included very important Eocene Orectolobiformes teeth and a super Megachasma from Chile. I want to credit @siteseer too though I am not sure what he is sending but I know it help tremendously lol Step 3 was figuring out how many display cases we would need and what sizes we would need. We knew that in addition to the displays by order, some sharks would get their own displays. For example, we have a lot of Lamniformes that we cover during our presentations but Goblin Sharks get special attention because kids really love them so they would get a separate display. The displays will not be of uniform size as some orders will be better represented. There will be more Carcharhiniformes than other orders for example. Size of the shark and size of the fossils also contribute to the need for a variation in display size. Step 4 is dismantling the old displays and putting together the new ones. This is on going and will not be finished until mid March probably. We need new labels which is taking a bit of time as there is a lot of shark fossils going into these displays. Step 5 will be displays of shark relatives. I think we will have one small one that will feature the three Stethacanthids we have, one small display for the two Eugenodontids and then another larger one to house the Batoids. We do cover shark relatives and they are quite popular with the students so these are important to the programs too. Kids love these wierdo creatues lol One of the really cool parts of this project is it allows me to think as an educator but also very much as a collector. I am an educator first and these fossils are for educational purposes but I consider myself a collector of shark fossils too. Doing this does allow me to add things that have educational value but also cross things off the personal list of sharks I want in the collection, like Megachasma and Mitsukurina. I can also view the collection and see areas where we can improve the quality of teeth at some point down the road. White Sharks and Cow sharks in particular will get an upgrade at some point. We can hunt for some of the rare Squaliformes teeth. Maybe we will track down a Ctenacanthus fin spine. Our goal is not just to tell the story of sharks but to show the story of sharks through the fossils. The people who invite us to present our fossils not only get to handle Megalodon teeth but they get close up examinations of a 300 million year old egg case, a Hybodus fin spine, shark vertebra and can compare the difference between Sawshark rostal teeth and Sawfish rostal teeth in their hands. I am quite proud of the hands-on education we give people and I think this project improves the overall impact. This project has also given us far more scientific knowledge and a far better understanding of shark classification. The learning has been invaluable really. Carter and I are both very passionate about sharks as we are with all of our programs but sharks have a special place. When he was a little guy, we would watch shark documentaries and this is an extension of that father son time for us. We knew this would require spending more money and take some time to do but we know it will be worth it. This will be a shark education program that will educate elementary students, museum patrons, college students and senior citizens. That is pretty darn cool I think. We also want to thank all of the forum members who contributed shark fossils and knowledge over the last year. This, like our other programs, would not be possible without the support, encouragement and generosity of TFF members. I apologize for the length of this post lol I have been really busy and have not been able to take the time to post about this and am pretty excited hence the rambling nature. I will post some pictures as we go through this and complete these. Pic 1 one of the boxes of shark fossils currently laying around our house lol It is a small box but there is quite a lot stored in there, just waiting for their permanent home.

I've recently heard about a Ctenacanthiform genus named Pyknotylacanthus from the Triassic of what is now Nevada and Idaho. The Ctenacanthiform genus consists of two species (P. spathianus and P. humboldtensis). What makes this genus so interesting is that while I've mostly heard that there is a gap in the fossil record between Permian and the Cretaceous where Ctenacanthiform fossils are recorded, this genus bridges that gap (if only by a little bit). G. Guinot, et al. (2013). Cretaceous stem chondrichthyans survived the end-Permian mass extinction. Nature Communication. 4:2669 doi: 10.1038/ncomms3669 https://www.nature.com/articles/ncomms3669 P. Davidson (1919). A cestraciont spine from the Middle Triassic of Nevada. University of California Publications, Bulletin of the Department of Geology 11(4): 433-435 R. J. Mutter and H. Rieber. (2005). Pyknotylacanthus spathianus gen et sp nov, a new ctenacathoid from the Early Triassic of Bear Lake (Idaho, USA). Revista Brasileira de Paleontologia 8(2): 139-148 There is also more recently another unnamed Ctenacanthiform recorded from the Triassic Arrow Rock section of the Oruatemanu Formation of New Zealand (this record also somewhat bridges the Permian-Cretaceous gap in Ctenacanthiform records). Grant-Mackie, & Yamakita, Satoshi & Matsumoto, & Hori, Rie & Takemura, & Aita, Yoshiaki & Takahashi, Satoshi & Campbell, Hamish. (2014). A probable shark dorsal fin spine fragment from the Early Triassic of the Arrow Rocks sequence, Whangaroa, northern New Zealand. New Zealand Journal of Geology and Geophysics. 57. 10.1080/00288306.2014.889722. https://www.researchgate.net/publication/265606171_A_probable_shark_dorsal_fin_spine_fragment_from_the_Early_Triassic_of_the_Arrow_Rocks_sequence_Whangaroa_northern_New_Zealand Iris Feichtinger, Andrea Engelbrecht, Alexander Lukeneder & Jürgen Kriwet (2020). New chondrichthyans characterised by cladodont-like tooth morphologies from the Early Cretaceous of Austria, with remarks on the microstructural diversity of enameloid, Historical Biology, 32:6, 823-836, DOI: 10.1080/08912963.2018.1539971 https://www.tandfonline.com/doi/abs/10.1080/08912963.2018.1539971?journalCode=ghbi20 What I'm really wondering is why has this Ctenacanthiform genus and it's confirmed presence in the Early Triassic been overlooked by most of the public (especially since the discovery of the Cretaceous Ctenacanthioform fossils in Europe in 2013 and 2020)?

As I have been researching large ctenacanthiform sharks from North America, I've been wondering if there are any known globally that are currently unnamed. I definitely know of the large Ctenacanthiformes Saivodus stratus (found in both what is now North America and Great Britain), the large Ctenacanthiform from the Permian Kaibab formation in Arizona, and the 'Texas supershark' (a likely large species of Gilkmanius) from the Pennsylvanian Texas Graham formation (all three as larger or larger than an adult Great White Shark (Carcharodon carcharias)). But are there any large ctenacanthiformes (at least in size comparable to a modern day adult Great white shark (Carcharodon carcharias)) currently unnamed that are also known? Ctenacanthiformes are known from North America, Greenland, Europe, Asia, and South America. https://www.mindat.org/taxon-P34476.html Even though study of Ctenacanthiformes as a whole is just starting to become more through within the past few decades, I'm wondering if anyone on the forum is aware of any currently unnamed Ctenacanthiform fossils from areas outside of North America of Great White Shark (Carcharodon carcharias)) size?

As I was recently doing some research on the prehistoric shark genus Cladodus, I came across some info that classifies the genus as a member of the family Cladoselachidae, Order Cladoselachiformes. https://en.wikipedia.org/wiki/Cladoselachidae This is somewhat confusing to me as mindat and the Paleontological Database aka fossilworks list Cladodus as a member of the family Ctenacanthidae, Order Ctenacanthiformes. https://www.mindat.org/taxon-8657177.html http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=104838 I'm personally leaning more towards Cladodus being a member of at least the Ctenacanthiformes. But I'm curious what are the origins of this taxonomic confusion on the genus Cladodus's phylogenetic placement in the Chondricthyan family? Is Cladodus a member of the Cladoselachiformes or Ctenacanthiformes? What do you guys think?

During the early part of the Serpukhovian stage of the Mississippian period, Carboniferous era around 330 Million years, a mass extinction occurred that wiped out between 13-39% of marine genera. Stanley, S. M. (2016, October 3). Estimates of the magnitudes of major marine mass extinctions in earth history. pnas.org. Retrieved December 30, 2022, from https://www.pnas.org/doi/10.1073/pnas.1613094113 McGhee, G. R., Sheehan, P. M., Bottjer, D. J., & Droser, M. L. (2012, February 1). Ecological ranking of Phanerozoic biodiversity crises: The Serpukhovian (early Carboniferous) crisis had a greater ecological impact than the end-Ordovician. Geology. Retrieved December 30, 2022, from https://pubs.geoscienceworld.org/gsa/geology/article-abstract/40/2/147/130800/Ecological-ranking-of-Phanerozoic-biodiversity?redirectedFrom=fulltext Its causes are still currently unknown and most marine genera groups recovered in the Pennsylvanian period. But I'm curious about the impacts this extinction event had on the diversity on Ctenacanthiformes and other Chondricthyian groups from the time and their subsequent recovery? What do you guys think? @Elasmohunter @Fossildude19 @deutscheben What do you think?

I've visited the Pennsylvanian Bond formation in Oglesby Illinois a few times but have only found a few cladodont teeth so far! I find a decent bit of teeth from crusher plate chondrichyans like Deltodus, but I've also heard there have been some large cladodont teeth found in the area. I'm just curious what is the largest cladodont teeth found in Oglesby Illinois?