deutscheben Posted August 12, 2017 Share Posted August 12, 2017 Over the last two years I have been able to collect a small but diverse group of shark and other chondrichthyan teeth from Pennsylvanian deposits in Illinois. Actually, all but one of the teeth are from one exposure of the La Salle Limestone of the Bond Formation- the other tooth was found in some roadside rip rap limestone in Central Illinois which seems to share many species with the La Salle, but unfortunately I have no way of determining the exact origin. Here is the first tooth, this is the one collected from rip rap in northern Champaign County. It is a cladodont type tooth, although unfortunately most of the main tooth and some of the cusps are missing. The tooth is 15 mm across at the widest point. 5 Link to comment Share on other sites More sharing options...
deutscheben Posted August 12, 2017 Author Share Posted August 12, 2017 I have posted the next two teeth in the Fossil of the Month contests and although they didn't win, they are still some of my favorite fossils that I have found so far. The first is a lovely little Peripristis semicircularis. It is about 12 mm wide. The second is a Cochliodus sp., which is about 25 mm long. 5 Link to comment Share on other sites More sharing options...
deutscheben Posted August 12, 2017 Author Share Posted August 12, 2017 The next tooth is the biggest I have found yet at this site, a Petalodus ohioensis. Although it was nearly complete when I found it, unfortunately the block it was in split between the crown and root after I got it home, which split the tooth as well. I have been slowly working on trying to prep out the parts that got separated and reassemble it. Thankfully the crown remained largely intact. I have also found some partial teeth at the site as well- the first image is an (I think) incomplete Chomatodus sp., which is 8 mm wide. Here are some of the other partial teeth I have recovered- a chunk of another Petalodus and a cladodont tooth that shattered when I tried to remove it from the 300 pound block it was in on one of my early trips to the site. I felt like a real idiot after that, and I now come prepared with the proper tools so I don't suffer heartbreak like that again. 5 Link to comment Share on other sites More sharing options...
ynot Posted August 12, 2017 Share Posted August 12, 2017 Nice collection. Link to comment Share on other sites More sharing options...
deutscheben Posted August 12, 2017 Author Share Posted August 12, 2017 Thanks! And finally, two more miniscule teeth. The first one is a mystery to me- it doesn't quite match any teeth I could find in my guidebooks, but it may just be a broken fragment. It is 6 mm across. And here is the last tooth and also the least at only 5 mm across- another cladodont of some sort. Although it's tiny, it is mostly complete, and I find its minute details enchanting. 4 Link to comment Share on other sites More sharing options...
Bullsnake Posted August 12, 2017 Share Posted August 12, 2017 Loving it! Can i ask what reference(s) you're using? Your Cochliodus sp. looks like Deltodus, but I'm no authority on the subject. I could certainly use some good references. Great collection! Steve Link to comment Share on other sites More sharing options...
deutscheben Posted August 12, 2017 Author Share Posted August 12, 2017 Thanks @Bullsnake! I use the Illinois Geological Survey published in the mid-1800s as a start, because it has illustrated plates of an enormous variety of fossils from my home state. A digital copy can be found online at the Internet Archive, too, so you don't need to own the physical books. After that, then I check this board, or the Oceans of Kansas site http://oceansofkansas.com or J-Elasmo site http://naka.na.coocan.jp/index.htm, all of which have many photos of Paleozoic shark teeth, and also have more up to date information on the correct classification of the teeth. 1 Link to comment Share on other sites More sharing options...
Fossildude19 Posted August 12, 2017 Share Posted August 12, 2017 These are wonderful! Thanks for showing us - I really like to see these early shark teeth. Regards, Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 IPFOTM -- MAY - 2024 _________________________________________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
ynot Posted August 13, 2017 Share Posted August 13, 2017 Nice finds! Thanks for sharing. Link to comment Share on other sites More sharing options...
fossilized6s Posted August 13, 2017 Share Posted August 13, 2017 Beautiful teeth! Thanks for sharing. ~Charlie~ "There are those that look at things the way they are, and ask why.....i dream of things that never were, and ask why not?" ~RFK ->Get your Mosasaur print ->How to spot a fake Trilobite ->How to identify a CONCRETION from a DINOSAUR EGG Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 In the last 3 years I have collected a fair number more shark, or to be more accurate, chondrichthyan, material from the Oglesby roadcut in LaSalle County, Illinois where most of these are from. These include both shark and holocephalian teeth. I will be posting examples as I get a chance to photograph them- first is one I am currently prepping. When I collected the block all that was visible was the piece below, and I wasn't even sure what I was looking at. As I was cleaning it up, I found a tiny partial petalodont crown of some sort on the top of the block. It has an interesting reddish color and is about 4 mm wide. After removing the section with that small tooth, I have been able to prep a little more from the larger one, revealing that what was visible was actually the flat bottom of a cladodont tooth root. So far I can see the base of the main cusp and 3 cusplets, with a 4th one mostly broken off. I'm hoping the others are all complete, though! 3 Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 Next is a partial holocephalian crusher tooth. I don't have an ID for this one, although it does have a distinctive pattern on the lower portion of the tooth, unlike the normal dimpled surface, it's more labyrinthine. 4 Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 Next is a more typical crusher tooth, possibly Deltodus or Sandalodus? When I found it, it was upside-down, with only a small portion of the root side exposed, so it was a delight when it popped out exposing the crushing surface. I didn't recognize what it was at the time, but now I have become familiar with the underside of these crusher teeth. Here is another example of what I now know is the underside of such a tooth- I have not tried to prep it out as it seems quite fragile and I'm afraid it would crumble. When I have time I may try to approach it from the side and see if can expose it that way. 5 Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 This is the lingual side of a Peripristis semicircularis crown- it is not as complete as the one above (which exposes the labial side) but I love the subtle black and grey coloring. 6 Link to comment Share on other sites More sharing options...
connorp Posted April 12, 2020 Share Posted April 12, 2020 These are some very nice finds! 3 hours ago, deutscheben said: Here is another example of what I now know is the underside of such a tooth- I have not tried to prep it out as it seems quite fragile and I'm afraid it would crumble. When I have time I may try to approach it from the side and see if can expose it that way. I just attempted this on a similar tooth. The entire underside of the base was exposed but nothing else. Wasn't 100% successful but not a complete failure either. Only advice I could give would be to stabilize the bottom with a lot of glue before touching it. On 8/12/2017 at 2:46 PM, deutscheben said: a cladodont tooth that shattered when I tried to remove it from the 300 pound block it was in on one of my early trips to the site. I felt like a real idiot after that, and I now come prepared with the proper tools so I don't suffer heartbreak like that again. Funny, the exact same thing happened with the cladodont tooth I'm prepping now. What kind of tools do you use for such extractions now? 1 Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 8 hours ago, connorp said: These are some very nice finds! I just attempted this on a similar tooth. The entire underside of the base was exposed but nothing else. Wasn't 100% successful but not a complete failure either. Only advice I could give would be to stabilize the bottom with a lot of glue before touching it. Funny, the exact same thing happened with the cladodont tooth I'm prepping now. What kind of tools do you use for such extractions now? Thanks for the advice on glue, I will try that. I don't have anything too advanced for extractions-the first time I was just using my regular Estwing rock hammer, but now I have a mini sledge, chisels, and a hacksaw with a carbide rod blade. With a few years of experience, I also think I have slightly better judgement now too. Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 I posted this next Petalodus ohioensis in the Fossil of the Month contest late last year. It is more complete and larger than the one above, although still have not been able to extract the left edge of the crown and root from the matrix. When I have more time I will work on that and prepping more of the lingual side of the root out. Too many fossils, not enough time! 5 Link to comment Share on other sites More sharing options...
RCFossils Posted April 12, 2020 Share Posted April 12, 2020 On 4/12/2020 at 12:34 PM, deutscheben said: I posted this next Petalodus ohioensis in the Fossil of the Month contest late last year. It is more complete and larger than the one above, although still have not been able to extract the left edge of the crown and root from the matrix. When I have more time I will work on that and prepping more of the lingual side of the root out. Too many fossils, not enough time! Beautiful specimen Link to comment Share on other sites More sharing options...
deutscheben Posted April 12, 2020 Author Share Posted April 12, 2020 3 hours ago, RCFossils said: Beautiful specimen Thanks! Link to comment Share on other sites More sharing options...
deutscheben Posted April 14, 2020 Author Share Posted April 14, 2020 Here is a another partial crusher tooth, possibly Deltodus? This one is pretty banged up. 2 Link to comment Share on other sites More sharing options...
deutscheben Posted April 27, 2020 Author Share Posted April 27, 2020 I finished exposing the cladodont tooth above- although it could still use a little clean-up, I'm very happy with how it turned out. The central cusp is almost 100% there, and I love that you can see the crown and the full depth of the root. After some research, I have identified it as Glikmanius occidentalis. 4 Link to comment Share on other sites More sharing options...
fossilsonwheels Posted April 27, 2020 Share Posted April 27, 2020 13 hours ago, deutscheben said: I finished exposing the cladodont tooth above- although it could still use a little clean-up, I'm very happy with how it turned out. The central cusp is almost 100% there, and I love that you can see the crown and the full depth of the root. After some research, I have identified it as Glikmanius occidentalis. I’m far from an expert but I agree with the ID. Great find and really nice tooth. 1 Link to comment Share on other sites More sharing options...
connorp Posted April 27, 2020 Share Posted April 27, 2020 I just scanned through the Handbook of Paleoichthyology and you're ID looks good. Absolutely spectacular tooth. 1 Link to comment Share on other sites More sharing options...
deutscheben Posted April 27, 2020 Author Share Posted April 27, 2020 12 hours ago, fossilsonwheels said: I’m far from an expert but I agree with the ID. Great find and really nice tooth. 40 minutes ago, connorp said: I just scanned through the Handbook of Paleoichthyology and you're ID looks good. Absolutely spectacular tooth. Thanks @fossilsonwheels and @connorp! This was my last definite find from the Oglesby roadcut in need of prepping. I'm thinking of smashing up some of my extra matrix from that site to see if I can find anything else. Link to comment Share on other sites More sharing options...
deutscheben Posted May 26, 2020 Author Share Posted May 26, 2020 After a day of bashing some of the extra La Salle Limestone I had lying around, I actually found a few tiny fish parts. Unfortunately I still don't have a micro-photography setup, so the pics are not the greatest. First is a partial and exceedingly tiny (2 mm tall) cladodont tooth- I will try to prep it out more, but under the magnifying scope you can see the typical wrinkles at the base of the broken cusp, and the distinctive "button" on the root. Next is an intriguing one- I am not sure exactly what it is, but I am nearly certain it comes from a fish. Only a tiny portion of typically fish texture/color was showing after I smashed the block, so I tried to prep it out. Unfortunately, the object itself was so frail and tiny it immediately shattered. However, it left a clear negative impression in the limestone. I seems like some sort of scale or denticle? It is 6 mm long. Link to comment Share on other sites More sharing options...
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