historianmichael Posted February 28, 2022 Share Posted February 28, 2022 These shark teeth were found in the Lower Cretaceous Del Rio Clay. I have seen posts on here that have identified Cretodus semiplicatus and Cretalamna appendiculata as the common shark teeth of the Del Rio Clay; however, none of these teeth seem to match up with photos I have seen of those teeth. Could these teeth simply be from a different position in the mouth than the ones in the photos I have seen? The measurements listed below are from the top of the root to the tip of the crown. Any help would be greatly appreciated. Thank you in advance! #1- 9mm #2- 7mm #3- 5mm Follow me on Instagram (@fossil_mike) to check out my personal collection of fossils collected and acquired over more than 15 years of fossil hunting! Link to comment Share on other sites More sharing options...
hemipristis Posted February 28, 2022 Share Posted February 28, 2022 (edited) the last one looks like a Squalicorax sp. Not sure what species, maybe S. falcatus? Edited February 28, 2022 by hemipristis 'Those who cannot remember the past are condemned to repeat it.' George Santayana Link to comment Share on other sites More sharing options...
historianmichael Posted February 28, 2022 Author Share Posted February 28, 2022 4 hours ago, hemipristis said: the last one looks like a Squalicorax sp. Not sure what species, maybe S. falcatus? I initially thought that the third one was a Squalicorax but I did not think that they ranged that far back. In doing further research I found an article that describes a number of species from the Albian of Texas. Follow me on Instagram (@fossil_mike) to check out my personal collection of fossils collected and acquired over more than 15 years of fossil hunting! Link to comment Share on other sites More sharing options...
ThePhysicist Posted March 5, 2022 Share Posted March 5, 2022 1,2. I'm thinking some kind of sand tiger, 2 could be goblin with the broader cusplet. 3. Squalicorax sp. "Argumentation cannot suffice for the discovery of new work, since the subtlety of Nature is greater many times than the subtlety of argument." - Carl Sagan "I was born not knowing and have had only a little time to change that here and there." - Richard Feynman Collections: Hell Creek Microsite | Hell Creek/Lance | Dinosaurs | Sharks | Squamates | Post Oak Creek | North Sulphur River | Lee Creek | Aguja | Permian | Devonian | Triassic | Harding Sandstone Instagram: @thephysicist_tff Link to comment Share on other sites More sharing options...
sixgill pete Posted March 5, 2022 Share Posted March 5, 2022 Have you tried finding a good reference on Texas Cretaceous sharks? A really good one is "The Collector's Guide to Fossil Sharks and Rays from the Cretaceous of Texas, by B. J. Welton and R. F. Farish" I have a paper copy somewhere, but not a digital file. The first tooth could be Odontaspis and the third strikes me as Psuedocorax, except for the root. Need to find my reference. 1 Bulldozers and dirt Bulldozers and dirt behind the trailer, my desert Them red clay piles are heaven on earth I get my rocks off, bulldozers and dirt Patterson Hood; Drive-By Truckers May 2016 May 2012 Aug 2013, May 2016, Apr 2020 Oct 2022 Link to comment Share on other sites More sharing options...
GPayton Posted March 5, 2022 Share Posted March 5, 2022 (edited) I've been to the Waco Pit (which is in the Del Rio Clay member of the Grayson Formation) probably at least seven or eight times this year and have found quite a lot of shark teeth in that time including two that look identical to your first and last pictures - the first I've identified as some species of Cretolamna, likely the same kind that is responsible for the majority of the teeth in the pit. I'm unsure if it's the same as Cretolamna appendiculata or some other species, because I had heard in one paper I can't remember the name of that there could be another. Either that or these straight teeth are just from a different position in the shark's mouth than the more recognizable wide curved ones. The last tooth I'd call Squalicorax like most have said, but I'd also add that it's almost definitely Squalicorax falcatus. For comparison: Edited March 5, 2022 by GPayton Link to comment Share on other sites More sharing options...
Adam86cucv Posted March 5, 2022 Share Posted March 5, 2022 2 hours ago, sixgill pete said: Have you tried finding a good reference on Texas Cretaceous sharks? A really good one is "The Collector's Guide to Fossil Sharks and Rays from the Cretaceous of Texas, by B. J. Welton and R. F. Farish" I have a paper copy somewhere, but not a digital file. The first tooth could be Odontaspis and the third strikes me as Psuedocorax, except for the root. Need to find my reference. I ordered a copy of that book from the Dallas Paleontological Society a few years ago, lots of good information in it. Here are a couple of pages that may be of use...if it's not ok to post the pages here please let me know and I will remove them or the mods will. 3 1 Link to comment Share on other sites More sharing options...
GPayton Posted March 5, 2022 Share Posted March 5, 2022 Thank you very much for posting the pages @Adam86cucv! I just ordered a copy of the same book myself a couple of days ago. The first anterior Carcharias amonensis tooth on the first page makes pretty much a perfect match for both my first tooth and the first one that @historianmichael posted. The laterals also make pretty good matches for the second one with the double cusplets as well. Link to comment Share on other sites More sharing options...
Coco Posted March 5, 2022 Share Posted March 5, 2022 Hi, 3 hours ago, GPayton said: IMG_6797.heic 314,17 Ko · 1 téléchargement IMG_6796.heic 307,83 Ko · 1 téléchargement HEIC files are not supported by the forum. Coco ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
GPayton Posted March 5, 2022 Share Posted March 5, 2022 56 minutes ago, Coco said: Hi, HEIC files are not supported by the forum. Coco Sorry @Coco, should be fixed now. For some reason the pictures upload like normal from my phone but would only show up as downloads when I did the same from my computer. Link to comment Share on other sites More sharing options...
Coco Posted March 5, 2022 Share Posted March 5, 2022 Coco ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
sixgill pete Posted March 5, 2022 Share Posted March 5, 2022 (edited) Thanks for posting those pages @Adam86cucv I believe the first one is C. amaonensis and possibly the second. Edited March 5, 2022 by sixgill pete Removed incorrect ID of the third tooth Bulldozers and dirt Bulldozers and dirt behind the trailer, my desert Them red clay piles are heaven on earth I get my rocks off, bulldozers and dirt Patterson Hood; Drive-By Truckers May 2016 May 2012 Aug 2013, May 2016, Apr 2020 Oct 2022 Link to comment Share on other sites More sharing options...
Adam86cucv Posted March 5, 2022 Share Posted March 5, 2022 10 hours ago, GPayton said: Thank you very much for posting the pages @Adam86cucv! I just ordered a copy of the same book myself a couple of days ago. 1 hour ago, sixgill pete said: Thanks for posting those pages @Adam86cucv No problem, glad I can help out. Link to comment Share on other sites More sharing options...
ThePhysicist Posted March 5, 2022 Share Posted March 5, 2022 4 hours ago, sixgill pete said: The third tooth I think Pseudocorax granti. P. granti is nonserrated and has a nutrient groove: 1 "Argumentation cannot suffice for the discovery of new work, since the subtlety of Nature is greater many times than the subtlety of argument." - Carl Sagan "I was born not knowing and have had only a little time to change that here and there." - Richard Feynman Collections: Hell Creek Microsite | Hell Creek/Lance | Dinosaurs | Sharks | Squamates | Post Oak Creek | North Sulphur River | Lee Creek | Aguja | Permian | Devonian | Triassic | Harding Sandstone Instagram: @thephysicist_tff Link to comment Share on other sites More sharing options...
sixgill pete Posted March 5, 2022 Share Posted March 5, 2022 2 hours ago, ThePhysicist said: P. granti is nonserrated and has a nutrient groove: Somehow, I completely missed that. Bulldozers and dirt Bulldozers and dirt behind the trailer, my desert Them red clay piles are heaven on earth I get my rocks off, bulldozers and dirt Patterson Hood; Drive-By Truckers May 2016 May 2012 Aug 2013, May 2016, Apr 2020 Oct 2022 Link to comment Share on other sites More sharing options...
siteseer Posted March 5, 2022 Share Posted March 5, 2022 (edited) Vullo et al, (2015) proposed a new genus for the species amonensis based on a partial skeleton from the Cenomanian of Morocco. https://www.tandfonline.com/doi/abs/10.1080/14772019.2015.1137983 I don't think that Squalicorax tooth should be identified as S. falcatus which has a less-rounded distal blade. The tooth shown has a more rounded one and the main cusp seems narrower toward the tip as in Albian forms. I'm not sure if the Squalicorax teeth from the Del Rio Clay have been named to species other than Squalicorax sp. It seems closer to S. curvatus if that is still a species in use. Edited March 5, 2022 by siteseer corrected term 1 Link to comment Share on other sites More sharing options...
MikaelS Posted March 25, 2022 Share Posted March 25, 2022 On 3/6/2022 at 6:27 AM, siteseer said: Vullo et al, (2015) proposed a new genus for the species amonensis based on a partial skeleton from the Cenomanian of Morocco. https://www.tandfonline.com/doi/abs/10.1080/14772019.2015.1137983 I don't think that Squalicorax tooth should be identified as S. falcatus which has a less-rounded distal blade. The tooth shown has a more rounded one and the main cusp seems narrower toward the tip as in Albian forms. I'm not sure if the Squalicorax teeth from the Del Rio Clay have been named to species other than Squalicorax sp. It seems closer to S. curvatus if that is still a species in use. The Del Rio Squalicorax was briefly discussed (and a tooth illustrated) in Siversson et al. 2019 (Anacoracid sharks and calcareous nannofossil stratigraphy of the mid-Cretaceous ‘upper’ Gearle Siltstone and Haycock Marl in the lower Murchison River area, Western Australia). 3 Link to comment Share on other sites More sharing options...
siteseer Posted March 28, 2022 Share Posted March 28, 2022 On 3/25/2022 at 2:19 AM, MikaelS said: The Del Rio Squalicorax was briefly discussed (and a tooth illustrated) in Siversson et al. 2019 (Anacoracid sharks and calcareous nannofossil stratigraphy of the mid-Cretaceous ‘upper’ Gearle Siltstone and Haycock Marl in the lower Murchison River area, Western Australia). Thanks. I will have to find that paper. Link to comment Share on other sites More sharing options...
MikaelS Posted March 29, 2022 Share Posted March 29, 2022 8 hours ago, siteseer said: Thanks. I will have to find that paper. Pm me your email address so I can send you a pdf. Link to comment Share on other sites More sharing options...
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