Fossildude19 Posted April 7, 2021 Share Posted April 7, 2021 12 minutes ago, RobinS87 said: Hey! Who is the expert in the matter. Can someone give a personal consultation? write to direct! You may consider writing a Personal Message to Tony Eaton, the author of this topic. He hasn't been online here in over a year, however. Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "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...
rocket Posted May 16, 2022 Share Posted May 16, 2022 just for showing, a very nice Ptychodus decurrens from middle turonian of Dortmund, nw-Germany, coming from the collection of a friend of mine 2 Link to comment Share on other sites More sharing options...
LSCHNELLE Posted May 16, 2022 Share Posted May 16, 2022 3 hours ago, rocket said: just for showing, a very nice Ptychodus decurrens from middle turonian of Dortmund, nw-Germany, coming from the collection of a friend of mine Beautiful Ptychodus tooth. What is the approximate tooth width and length? Link to comment Share on other sites More sharing options...
rocket Posted May 16, 2022 Share Posted May 16, 2022 thanks, wide is around 40 mm Link to comment Share on other sites More sharing options...
rocket Posted May 16, 2022 Share Posted May 16, 2022 Another one, Ptychodus latissimus, wide is around 50 mm, lower Turonian, Dortmund 3 Link to comment Share on other sites More sharing options...
LSCHNELLE Posted May 17, 2022 Share Posted May 17, 2022 Monster Ptychodus latissimus! Beautiful! 1 Link to comment Share on other sites More sharing options...
rocket Posted May 17, 2022 Share Posted May 17, 2022 48 minutes ago, LSCHNELLE said: Monster Ptychodus latissimus! Beautiful! thanks, yes, it is a fantastic one. We stored it in a museum some years ago, perhaps someone will work on it one day. I thought about but never found the time... Link to comment Share on other sites More sharing options...
rwise Posted May 25, 2022 Share Posted May 25, 2022 (edited) Here are a couple of mine...looking to confirm IDs ....Ptychodus decurrens?? And last one Ptychodus anonymus????? Edited May 25, 2022 by rwise Thanks for your help in advance. Link to comment Share on other sites More sharing options...
LSCHNELLE Posted May 25, 2022 Share Posted May 25, 2022 (edited) Nice teeth! I would think Ptychodus latissimus for both. Notes: (1) see most recent tooth posted here before yours; (2) typically fewer ridges (six each) than other Ptychodus; (3) sharp cutting edge on ridge tops with long wave-like swaths between ridges; (4) low crown height; and (5) granular marginal texture. Edited May 26, 2022 by LSCHNELLE typos 2 Link to comment Share on other sites More sharing options...
LSCHNELLE Posted June 3, 2022 Share Posted June 3, 2022 On 5/25/2022 at 5:52 PM, LSCHNELLE said: Nice teeth! I would think Ptychodus latissimus for both. Notes: (1) see most recent tooth posted here before yours; (2) typically fewer ridges (six each) than other Ptychodus; (3) sharp cutting edge on ridge tops with long wave-like swaths between ridges; (4) low crown height; and (5) granular marginal texture. @rwiseAbove is my opinion in case you want to know. Your question might be better reviewed in the Fossil ID section. Your first tooth is likely NOT P. decurrens because P. decurrens typically has low crown with about 8 to 12 parallel ridges that extend to the tooth margin and then bifurcate. Yours has only the low crown aspect of those four characteristics and the ridges terminate well before the marginal edge. It only has six ridges. 3 Link to comment Share on other sites More sharing options...
LSCHNELLE Posted September 3, 2022 Share Posted September 3, 2022 On 11/29/2016 at 1:14 PM, LSCHNELLE said: The UT students said the huge single Ptychodus tooth was not a trustworthy ID as P. Rugosus - even though they can be up to 80mm wide. My understanding from Shawn Hamm's MS paper is that P. Rugosus has a bulbous and often offset from center crown which this tooth did not have. This tooth looks more like a huge P. Marginalis because of the concentric circles. Or, if from England, it could be P. Polygyrus. The dentition is a harder ID. I would guess that it is a very large P. Decurrens due to its bifurcating transverse ridges extending to marginal edge and due to its numerous fine ridges on the labial and lingual margins perpendicular to the transverse ridges. Shawn Hamm gave his opinion on the dentition a few years ago. He first thought P. occidentalis based on the photo only. 1 Link to comment Share on other sites More sharing options...
siteseer Posted September 21, 2022 Share Posted September 21, 2022 On 1/14/2021 at 8:38 AM, Seaspawn said: These are honestly beautiful. Geographically speaking I'm guessing they're mostly found in the southern region of North America? I honestly would not have known at a glance that this was a tooth at all. Thanks so much for the guide. Ptychodus teeth are also found in Kansas, Oklahoma, Utah, Wyoming, Colorado, South Dakota, Montana, and Canada. 1 Link to comment Share on other sites More sharing options...
truceburner Posted September 22, 2022 Share Posted September 22, 2022 On 9/20/2022 at 7:18 PM, siteseer said: Ptychodus teeth are also found in Kansas, Oklahoma, Utah, Wyoming, Colorado, South Dakota, Montana, and Canada. And Russia. https://instagram.com/irenochka62?igshid=YmMyMTA2M2Y= Link to comment Share on other sites More sharing options...
siteseer Posted September 23, 2022 Share Posted September 23, 2022 8 hours ago, truceburner said: And Russia. https://instagram.com/irenochka62?igshid=YmMyMTA2M2Y= And England, France, Kazakhstan, and Japan. Link to comment Share on other sites More sharing options...
mike23 Posted November 24, 2022 Share Posted November 24, 2022 these are really cool. Seeing the teeth from Denton Co, makes me hopeful I might find some in my hunting grounds. Link to comment Share on other sites More sharing options...
LSCHNELLE Posted November 24, 2022 Share Posted November 24, 2022 On 5/16/2022 at 5:19 AM, rocket said: just for showing, a very nice Ptychodus decurrens from middle turonian of Dortmund, nw-Germany, coming from the collection of a friend of mine @rocket Based on Middle Turonian age and the rounding at the margin, I think that this is more likely a Ptychodus marginalis. Link to comment Share on other sites More sharing options...
rocket Posted November 25, 2022 Share Posted November 25, 2022 11 hours ago, LSCHNELLE said: @rocket Based on Middle Turonian age and the rounding at the margin, I think that this is more likely a Ptychodus marginalis. oh, thanks, I will talk to my friend and check Link to comment Share on other sites More sharing options...
LSCHNELLE Posted November 25, 2022 Share Posted November 25, 2022 (edited) 5 hours ago, rocket said: oh, thanks, I will talk to my friend and check @rocket Ptychodus decurrens can be Middle Turonian at its youngest age. Maybe, the other side of your tooth has dendritic branching of ridges to the edge of the margin. If so, then it is properly diagnosed as Ptychodus decurrens. If the ridges are also rounded with a broader margin, then it more likely is Ptychodus marginalis. Again, without an associated set of teeth, this is only an educated guess based on tooth morphology. Edited November 25, 2022 by LSCHNELLE 1 Link to comment Share on other sites More sharing options...
rocket Posted November 25, 2022 Share Posted November 25, 2022 (edited) 15 minutes ago, LSCHNELLE said: @rocket Ptychodus decurrens can be Middle Turonian at its youngest age. Maybe, the other side of your tooth has dendritic branching of ridges to the edge of the margin. If so, then it is properly diagnosed as Ptychodus decurrens. If the ridges are also rounded with a broader margin, then it more likely is Ptychodus marginalis. Again, without an associated set of teeth, this is only an educated guess based on tooth morphology. thanks again. Always complicated with the Ptychodus... when we wrote a paper about the fauna (total fauna, fishes had been only less than 10%) from there many years ago we had several Ptychs we did not 100% know... Nice literature about english and a bit about german Ptychs, but not absolutely sufficient... Edited November 25, 2022 by rocket Link to comment Share on other sites More sharing options...
LSCHNELLE Posted March 14, 2023 Share Posted March 14, 2023 (edited) On 7/25/2010 at 3:30 PM, Tony Eaton said: I'm recycling some content from a prior post to cobble together a quick, non technical guide to ID Ptychodus teeth. Many of the pictures below are from CreekCrawler. A few terms: transverse ridges = the lines going across the tooth crown = the abrasive "eating" surface of the tooth margin = the area around the crown above the root flat crowned, from oldest to youngest: Ptychodus decurrens low crown with ridges that split (bifurcate) to the end of the marginal area http://farm5.static.flickr.com/4076/4807278088_118329b99a.jpg Ptychodus marginalis (polygyrus) crown only moderately raised ridges circle crown at marginal area and margin has a circular "finger print" pattern unlike decurrens http://farm5.static.flickr.com/4081/4807277210_fed82602c1.jpg Ptychodus latissimus few, thick, "sharp" ridges on the low crown little marginal area http://farm5.static.flickr.com/4121/4806655695_1ec3a110f0_m.jpg Ptychodus martini very low crown, unlike decurrens and marginalis the marginal area is rough or non existent and has no discernable pattern more ridges and generally more rectangular compared to litissimus http://farm5.static.flickr.com/4098/4827562753_f387287fd7.jpg high crowned, oldest to newest: Ptychodus anonymus small in general 10+ ridges rough margin crown lower than whipplei and more rounded than mammillaris http://farm5.static.flickr.com/4135/4827323677_c734855de1_b.jpg Ptychodus occidentalis gently curved high crown at a slight angle to margin unlike mammillaris 10+ fine ridges ridges branch into the marginal area unlike anonymous http://farm5.static.flickr.com/4035/4673307815_9b5e843d2a.jpg Ptychodus mammillaris crown attached at a steep angle to the marginal area unlike occidentalis ridges are course and crown wider/squarer than anonymous marginal area has a circular pattern around the crown http://farm5.static.flickr.com/4137/4806655949_af319493f6.jpg Ptychodus whipplei very high crowned, peg like transverse ridges generally do not extend to the margin Ptychodus mortoni the crown is pointed with ridges running together meeting at a single point at the top of the crown http://farm5.static.flickr.com/4073/4828264368_9dc6bef454.jpg Ptychodus atcoensis (sp.) front to back (labial to lengual) median line thick ridges that form a "chevron" pattern recenly named by Shawn Hamm, previously Ptychodus sp. http://farm5.static.flickr.com/4076/4827431719_7fbe50bd14.jpg Ptychodus rugosus most rare Ptychodus at least in Texas, no pictures to post ;-) transverse ridges are rough and poorly defined, almost giving the ridges a heavily "rusted" outline Orginal post with some other great picks from kknight. http://www.thefossilforum.com/index.php/topic/14366-ptychodus-occidentalis/ It's time for an addition to this post for Ptychodus hunters who find a strange looking miniature version of these species from the Upper Medial (UMF) or upper centerline (aka symphosial) tooth file. These UMF teeth are a fraction of the medial file tooth size and they have similar marginal and ridge patterns to the characteristic medial file teeth. They have an oversized root and a strangely proportioned crown. It's usually much narrower from side-to-side (labial/lingual) than in the front-to-back (anterior/posterior) direction. Otherwise, Ptychodus medial file teeth are usually rectangular to square with somewhat rounded corners and the largest dimension is primarily width-wise. Here are five species in age order, four which I collected and the last one found by @JohnJ with @Jared Con a shared adventure. Ptychodus anonymous (Middle Cenomanian to Middle Turonian) Not the best image - pictured through my glass display. Ptychodus occidentalis (Middle Cenomanian to Middle Turonian) Ptychodus marginalis (Late Cenomanian to Late Turonian) Ptychodus decurrens (Late Cenomanian into Turonian) - not yet verified by Shawn Hamm) Ptychodus new species (Middle to Late Turonian) - not yet verified by Shawn Hamm because he has never seen an UMF example) Please add any verified UMF teeth you might have that aren't listed here (such as P. whipplei, P. rugosus, P. polygyrus, or P. mortoni. Edited March 15, 2023 by LSCHNELLE Inserted images between text. Corrected the person who found the last UMF tooth. 3 Link to comment Share on other sites More sharing options...
Jared C Posted March 14, 2023 Share Posted March 14, 2023 7 hours ago, LSCHNELLE said: Here are five species in age order, four which I collected and one collected by @Jared Con a shared adventure. To be fair, it was actually @JohnJ that spotted that tooth during the excavation, though the tooth will join the collection ranks of fossils found affiliated with that excavation 1 “Not only is the universe stranger than we think, it is stranger than we can think” -Werner Heisenberg Link to comment Share on other sites More sharing options...
LSCHNELLE Posted March 15, 2023 Share Posted March 15, 2023 3 hours ago, Jared C said: To be fair, it was actually @JohnJ that spotted that tooth during the excavation, though the tooth will join the collection ranks of fossils found affiliated with that excavation Thanks @Jared C. I just corrected the post, but I kept you in the adventure. 2 Link to comment Share on other sites More sharing options...
Mikrogeophagus Posted April 24, 2023 Share Posted April 24, 2023 I was told this UMF would be useful here . Suspected to be Ptychodus marginalis from the Middle Turonian Kamp Ranch of North Texas. 1 Link to comment Share on other sites More sharing options...
Syndy Posted May 6, 2023 Share Posted May 6, 2023 On 7/26/2010 at 6:31 PM, Tony Eaton said: Hieronymus, thanks for the feedback. I enjoy the debate :-) I have just taken a picture that might be a better diagnostic example. Here is a picture of 2 teeth roughly the same size from the same site (middle Turonian, Kamp Ranch Fm., Denton Co.) http://farm5.static.flickr.com/4112/4832923794_a3411304c6.jpg The tooth on the left is mammilaris, the one on the right anonymous. They have more or the same margin design and same ridge count, but the difference is that mammilaris is much more squared off (flat) at the top of the crown. I have several teeth that are less clear cut and seem to be variations between mammilaris, anonymous, and even a bit like mortoni or atcoensis. The picture of anonymous in my post above includes a tooth, (second tooth on the bottom left) that I might consider mammilaris judging by just that picture. In the pictures I included originally of mammilaris, the tooth on the right has a flat crown, but it is more narrow compared to most "mammilaris" that I've collected and at the angle I picked it is not clear. Here is another view where the flat crown is more obvious. http://farm5.static.flickr.com/4120/4807277936_b20c76427d_m.jpg Unless I saw a naturally associated tooth set that showed morphology of both the flat and rounded crowns I would not agree that anonymous is a nomen dubium (doubtful name). It looks like the roof of a mouth, feline. Link to comment Share on other sites More sharing options...
LSCHNELLE Posted May 6, 2023 Share Posted May 6, 2023 On 11/26/2016 at 4:49 PM, LSCHNELLE said: Pics of Ptychodus teeth dentition with slightly out of focus larger tooth. Also, age chart - modified by me for Austin courtesy of Shawn Hamm's thesis. Shawn Hamm told me a while back that this dentition looked like Ptychodus occidentalis. Based on the crown height and multiple finer ridges, I think that is a good possibility. But I am not entirely sure. Both Ptychodus decurrens and Ptychodus occidentalis would be very rare dentitions to find in the Western Interior Seaway. UT students said it was donated without an understanding of where it came from. Link to comment Share on other sites More sharing options...
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