Multicusp Posted June 18, 2012 Share Posted June 18, 2012 Some past discussion posted here outlined the units of River Bend formation found in the Onslow County regions and the species specific nature of these units. There is 1 location at the present time that has unearthed River Bend fossils and it is approximately 8 miles North of the Bel Grade Quarry. I guess the question that was raised prior on the forum is whether this material is Oligocene, or Eocene. I have found late Eocene to early Oligocene species in this deposit and many transitional species as well. Onslow County is a primary Eocene formation in most excavations that I have ever collected from and Castle Hayne material is normally the main deposit, this is very different than the normal exposures for the area and some of the other formation members include Spring Garden and Comfort per the U.S.G.S. The River Bend is appearently a very uncommon part of the Eocene/Oligocene Castle Hayne members here. Please feel free to add any undocumented, or unknown cases of this strange and rare deposit. Link to comment Share on other sites More sharing options...
Al Dente Posted June 21, 2012 Share Posted June 21, 2012 You should post some pictures of your transitional species. If they are from the River Bend Formation then they are Oligocene, unless they have been reworked which isn't unusual for shark teeth and bones. The River Bend is more common in Jones County where it crops out along the streams. It is the limestone that is quarried in the Belgrade Quarry and also occurs in the old New Bern quarry. Link to comment Share on other sites More sharing options...
DeloiVarden Posted June 21, 2012 Share Posted June 21, 2012 I am looking forward to the pics Link to comment Share on other sites More sharing options...
Paleoc Posted June 24, 2012 Share Posted June 24, 2012 Belgrade formation is latest Oligocene River Bend formation is older Oligocene Link to comment Share on other sites More sharing options...
Multicusp Posted June 25, 2012 Author Share Posted June 25, 2012 That makes complete sense with these late Ric teeth mixing with early Angustiden teeth. I am familiar with the Bel Grade material and it is a very coarse rock compares to this version of River Bend, sediment is dominant much like Yorktown. Link to comment Share on other sites More sharing options...
Multicusp Posted June 27, 2012 Author Share Posted June 27, 2012 Link to comment Share on other sites More sharing options...
Multicusp Posted June 27, 2012 Author Share Posted June 27, 2012 Onslow late Auriculatus & early Angustidens found in the same deposit - no reworking here, Link to comment Share on other sites More sharing options...
Multicusp Posted June 29, 2012 Author Share Posted June 29, 2012 Here are some of the little guys from the same deposit as the big guys. More to photo and add later. Link to comment Share on other sites More sharing options...
Al Dente Posted July 20, 2012 Share Posted July 20, 2012 Onslow late Auriculatus & early Angustidens found in the same deposit - no reworking here, I was meaning to respond to this post but forgot. Your second photo with the smaller teeth looks similar to some of the finds I have from the Belgrade quarry (Oligocene) but the photo isn't very easy to see. Your Carcharocles teeth look like they might be an upper lateral tooth and a lower anterior tooth. Lower teeth tend to be thicker and narrower. Carcharocles tend to be highly variable in shape and I don't know of a good way to differentiate C. auriculatus from C. angustidens except C. angustidens can get larger and are sometimes proportionately thinner depending on tooth position. Link to comment Share on other sites More sharing options...
Multicusp Posted July 20, 2012 Author Share Posted July 20, 2012 I collect Ric teeth as a regular habit and there are some very evident differences between these teeth...Agustiden no longer supports the tooth by standing on the root end, the Ric does, in certain position and form. These two teeth have combined charactaristics that show transition from Angy to Ric, one has incorparated cusps into the blade, the other does not and has the distinctive ragged serations on only 1 cusp. They are from the fine line between extreme late Eocene and early Oligocene. 1 is definate Ric, the other is definate early Angustiden. Not typical fro Onslow County formation, but this is an isolated case of rare River Bend. Link to comment Share on other sites More sharing options...
Multicusp Posted July 20, 2012 Author Share Posted July 20, 2012 I collect Ric teeth as a regular habit and there are some very evident differences between these teeth...Agustiden no longer supports the tooth by standing on the root end, the Ric does, in certain position and form. These two teeth have combined charactaristics that show transition from Angy to Ric, one has incorparated cusps into the blade, the other does not and has the distinctive ragged serations on only 1 cusp. They are from the fine line between extreme late Eocene and early Oligocene. 1 is definate Ric, the other is definate early Angustiden. Not typical fro Onslow County formation, but this is an isolated case of rare River Bend. Whoops! Ric to Angy is what I meant. Link to comment Share on other sites More sharing options...
Al Dente Posted July 20, 2012 Share Posted July 20, 2012 (edited) Agustiden no longer supports the tooth by standing on the root end, the Ric does, in certain position and form. These two teeth have combined charactaristics that show transition from Angy to Ric, one has incorparated cusps into the blade, the other does not and has the distinctive ragged serations on only 1 cusp. There are a couple of publications you should look at. One is Richard Chandler's Cretaceous and Paleogene Fossils of North Carolina. In this publication on page 33 he illustrates 5 C. auriculatus teeth demonstrating the highly variable nature of the lateral cusps. The other publication is An associated specimen of Carcharodon angustidens from the late Oligocene of New Zealand by Gottfried and Fordyce. In this publication they describe a specimen that contained 165 teeth plus vertebrae. It is a single individual shark and the authors make a point to demonstrate the high amount of variability in the teeth there is within this one individual shark. Their figure 4 shows 3 teeth with high variation in the side cusps, one tooth with only a hint of a cusp, one with a cusp attached to the blade and one with the cusp separated by a notch. You mentioned auriculatus being able to stand on the root. I have seen this demonstration on the Black River Fossils website. I can tell you that my auriculatus from South Carolina will sit on their roots but all of mine from the Castle Hayne Formation have thinner roots and won't stand. Edited July 20, 2012 by Al Dente Link to comment Share on other sites More sharing options...
Paleoc Posted July 20, 2012 Share Posted July 20, 2012 (edited) This is the type specimen of angustidens from an associated dentition in the Oligocene of Belgium. Note this is what most people would call auriculatus. Edited July 20, 2012 by Paleoc Link to comment Share on other sites More sharing options...
Multicusp Posted July 20, 2012 Author Share Posted July 20, 2012 I have seen the publication on this single Angy find. The teeth that I posted in this thread are a Ric and an Angustiden though. I also have some nice large Ric teeth from Eocene Castle Hayne and they stand on the root, however there are many, as stated, certain position & form that do not. I realize that these two versions of Carcharocles are very difficult because of the many variations. I have found nothing but Auriculatus in this region for close to 20 years until the Angustiden in this thread showed up in Oligocene material. I agree that Angustiden teeth are frequently mistaken for Auriculatus. Mine is positively Angustiden, I'll do some more comprehensive photos for the thread with some good close up detail on both of these specific teeth. Onslow County is 90% late Eocene with reworked layers over the primary Castle Hayne cap rock and we are a hot spot for big late Rics. Link to comment Share on other sites More sharing options...
Multicusp Posted July 23, 2012 Author Share Posted July 23, 2012 To keep on topic here I have put the River Bend teeth in a different more comparative set up. This may, or may not solve what they really are, but anyone who is more qualified than I is welcome to make the call. As I noted above, Onslow County is not known for Oligocene species for the most part and I have found no les than a few hundred true Auriculatus in several private & commercial pits in the region. The larger tooth looks nothing like any Ric that I have, but the smaller tooth does have many like features including the root stand. Link to comment Share on other sites More sharing options...
Paleoc Posted July 23, 2012 Share Posted July 23, 2012 Keep in mind that the same shark may have a mix of more modern and more ancient teeth in its mouth at the same time (particularly juveniles). Case in point, I have a juvenile Great white jaw that has fully serrated, almost completely unserrated, cuspleted and uncuspleted teeth in its mouth. Independently found as fossils they might be identified as 2 or 3 species. Root nubs are another case in point. I have megalodons with protective nubs while most megalodons do not have them. Not a identifying feature. Link to comment Share on other sites More sharing options...
Multicusp Posted July 23, 2012 Author Share Posted July 23, 2012 The nubs were pointed out because that particular feature did carry over to the Megalodon in isolated cases, as you have pointed out, but was first noted on Angustidens. The smaller tooth is a 2 & 1/4", I don't think it is from a juvenile based on the jaw position at latteral. I do have a juvenile tooth from this same deposit though. As far as the max size for Auriculatus, they have been found in excess of 4" and the standing record at 5" plus. The old grey Ric above is just a hair under 4" , Castle Hayne Fm. Onslow County, NC. Angustidens are bigger in more frequency, but the big Rics are out there too if your in the right stuff. Link to comment Share on other sites More sharing options...
Al Dente Posted July 23, 2012 Share Posted July 23, 2012 The nubs were pointed out because that particular feature did carry over to the Megalodon in isolated cases, as you have pointed out, but was first noted on Angustidens. Is this documented? Here is an auriculatus (Eocene) from Africa with nubs that I found on the internet. I have a South Carolina auriculatus in my collections with nubs.. Link to comment Share on other sites More sharing options...
Multicusp Posted July 24, 2012 Author Share Posted July 24, 2012 I have indicated early in the thread that I suspect the Ric that I found is extreme late Eocene, possibly around 39 MYA. Your teeth from Africa and SC are also late Eocene, I believe, and now given the Sokolowi title, somewhere between the Ric to Angy. Just like Isaurus to the GW that started from upper root down the the blade with seration, it appears that sharks transition to the next step from the top of the tooth & root downward to whatever the next version would be. The answer to the question on documented is yes, Wikipedia I believe has an Angy publication that coins the nubs as an early version of what the Megalodon roots would produce, obviously not all Megs. but there are even Chubentensis that have them.The photo, not too clear because of the showcase, is a 3" NC Auriculatus, approx. 42 MYA.No nubs and no visable transitioning traits. Link to comment Share on other sites More sharing options...
Multicusp Posted July 26, 2012 Author Share Posted July 26, 2012 Better River Bend Oligocene non-Bel Grade teeth. Killer stuff though, Ric, Angy, or not. Link to comment Share on other sites More sharing options...
MikeDOTB Posted July 30, 2012 Share Posted July 30, 2012 (edited) Multicusp! You joined and only took me a second to figure out who you were. Yes I did post some of those teeth on here and I think brought up the subject of age. I'm now gonna go back and read through the topic, but anyways welcome to the forum! Edited July 30, 2012 by MikeDOTB DO, or do not. There is no try. Link to comment Share on other sites More sharing options...
Multicusp Posted July 30, 2012 Author Share Posted July 30, 2012 I had found some of your thread replies, but could'nt get back to your River Bend post. Anyway, I guess you can see that the forum regulars have responded to these teeth with tons of info and healty speculation, debate, etc. How are your large GW's doing at GMR? My Ric teeth in the Eocene boneyard have been very cooperative lately, along with the Eocene Makos. This is a very easy Forum to operate! Talk soon. Link to comment Share on other sites More sharing options...
MikeDOTB Posted July 30, 2012 Share Posted July 30, 2012 Hey MC, my great white collection hasn't changed much at all unfortunately, but I've found a few interesting things lately. Which reminds I have to take some pictures for fossil of the month! DO, or do not. There is no try. Link to comment Share on other sites More sharing options...
Multicusp Posted July 30, 2012 Author Share Posted July 30, 2012 Must be a special fossil to rate fossil of the month. I'll be posting some more well preserved River Bend here, Nortorynchus, Hemi Curvatus, Mako, and if all goes well hopefully another Super Auricustiden Angulatus, new species I think? Link to comment Share on other sites More sharing options...
RickNC Posted July 30, 2012 Share Posted July 30, 2012 Pretty sure I know who you are. Welcome. Mike has no luck with GW's. Doesn't look like he will ever find a really big one. Link to comment Share on other sites More sharing options...
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