A Classic Hunt on the NSR

[Mikrogeophagus]

I think North Texans will relate when I say that now and then, the urge to take a drive out to the NSR and spend the day hunting some Campanian gravel bars can spontaneously take complete hold. I had one of those moments just after the series of heavy rains and powerful winds our region encountered some days ago. Previously, my luck with weather at the NSR had been rather poor. Each time, the temps were either nearing a hundred degrees or only just above freezing, making a full on adventure crossing muddy waters and crawling atop unshaded gravel beds too much to handle. I had yet to experience a proper adventure at this historic site, so I decided that this week would be the one where I changed that. Luckily, my friends @PaleoPastels(Lari) and Cole where kind enough to invite me out to their special spot along the river. After waking up bright and early, I got in my car and followed the rising sun.

 

After jumping out of our vehicles and exchanging brief greetings, we quickly slid our way down to the shale bed and beelined for the first bar. Cole has a bit of an aversion for water, so he stuck around at the entrance for most of the day while Lari and I got our clothes wet hopping from bar to bar. The weather and water temp were absolutely perfect, and the lack of footprints assured us it would be a productive day. It's not often you beat the crowd to a place as popular as this! Although I maintained measured expectations coming in, the sheer variety of strange and interesting fossils/artifacts that are known to come from this area kept me on my toes from the outset.

 

When we arrived to the first bar, we started off strong, picking up a variety of shark teeth. Lari had an eye for them, immediately spotting a few super big Scapanorhynchus texanus, a staple of the Ozan Formation. Despite my protests, she was very generous in donating a few to me due to my limited NSR collection . 

 

Finally one I spotted myself! Scapanorhynchus texanus

 

Scapanorhynchus texanus of the day. Some may be Carcharias samhammeri as I am still working on differentiating the two.

 

In between crawling the gravel, I did some sifting which yielded a few interesting specimens including Squalicorax kaupi, Cretalamna sarcoportheta, Carcharias samhammeri, and a vole tooth which I will ignorantly assume to be Pleistocene in age.

 

Cretalamna sarcoportheta, Squalicroax kaupi, and Carcharias samhammeri

 

Sifting also yielded a plethora of shark vertebrae and I was fortunate enough to come across a beautiful spiral shark coprolite. I found one solitary coral which I assume is Trochocyathus sp.

 

Shark verts, shark coprolite, and Trochocyathus sp.

 

As I scanned the gravel looking to spot a complete Cretalamna, I was instead met with the first mosasaur tooth of the day! It was mostly in tact and showed some nice detail. I was relieved to know the entire trip was already made, and I could spend the rest of my time playing with house money. The only other mosasaur tooth previously in my collection has a beat up crown, so this new specimen certainly complements it.

 

Don't know much about mosasaur genera in the NSR, but I will go with Tylosaurus proriger for now.

 

Throughout the day, we also found tons of very large Enchodus fangs and jaw sections. I'm so used to finding these teeth in their miniature forms as I sift for micros, I almost forgot how big they could get. Lari did good with spotting the Ischyrhiza mira rostral teeth and quickly built up a small collection. She was nice enough to give a large one to me.

 

Top: Fused fish vert and Pachyrhizodus tooth. Bottom: Enchodus jaw section and large fangs.

 

Ischyrhiza mira

 

By now we had hopped a couple of gravel bars and there was still plenty ways to go. It took me longer than it should have, but reaching the third bar finally brought me a large tumbled mosasaur vertebra. Not far from it, there was a section of finer gravel. Used to the routine, I once again got close to the ground and began scanning every pebble. After tossing the millionth shrapnel of shark tooth, I finally locked eyes with the most perfect mosasaur tooth I had ever seen. As I picked it up, I could tell something wasn't right, however. Of course the best side was on full display, but the rest of the tooth was cleaved cleanly off. Oh well, at least it'll look nice in pictures. Not long after, I found a second mosasaur tooth that was decently complete and hooked albeit tiny.

 

Two nicest mosie verts.

 

 

A slice of an exquisitely preserved mosasaur crown.

 

The next oddball find came awhile later. My initial impression was that it might have been a segment of a Xiphactinus tooth, but the curvature suddenly ended along one of the edges of it. At this sudden end, there were two columns of small protrusions running longitudinally. I was debating on throwing it out, but my history of carelessly tossing neat finds convinced me to play it safe and take it home for identification. I'm glad I did because after the hunt, I immediately googled my hunch and it seems to be correct. This is a fragment of a hybodont spine! I wish I could pin down a more specific ID, but the info on them seems limited. I will say that, out of Moss Creek, I had found a tooth belonging to Lonchidion babulskii last year which could be the culprit. Quite an uncommon find for the NSR! Wondering if any shark experts here might have any ideas @ThePhysicist@Al Dente. 

 

Hybodont fin spine. Lonchidion babulskii is a candidate.

 

By the penultimate gravel bar, I thought the best finds had surely been made. All day Lari had been talking about how this was THE spot to find Globidens teeth and how every visit she would find at least one fragment. Well, the walkable land was starting to run out and she expressed how disappointing it would be not to come across one that day. I find Globidens to be really interesting, but I think of it as one of those finds I would never expect to make on any given hunt. For me, not finding one would not define the day as a let down. As I was beginning to form those thoughts into words, I reached down to pick up a circular fragment of a tooth with a peculiar texture. Finding the right angle of light soon revealed the undoubted best find of the day: The top of a Globidens sp. crushing tooth!

 

The whole day I had been hallucinating "finding" Ptychodus teeth. Funnily enough, this may very well be the tooth that ended their supremacy as shell crushers of the WIS. Seems too coincidental that Globidens suddenly appears right around the last occurrence of Ptychodus. I wonder if they directly competed Ptychodus out of existence or if Ptychodus went extinct on its own and mosasaurs simply filled in the niche .

 

I don't think the Globidens of the Ozan Formation has been formally described yet. Globidens sp. 

 

Mosasaur teeth of the day!

 

Despite having hunted for over a year in the creeks of Austin, I am surprisingly bad at spotting artifacts. Throughout the span of the day, the both of us had found a few chert flakes, but no sign of anything more even as I was trying to make a conscious effort to spot one. On the same bar as where the Globidens sp. was found, I noticed a worked edge of stone so big even someone as archaeologically blind as me could never miss it. Without an ounce of self control, I yanked it from the sand before I could finish yelling the word "arrowhead"! I seriously need to work on milking the moment . I did a little bit of searching online later and found that the point is likely a Darl or Hoxie. Both put its age in the thousands of years! 

 

Darl or Hoxie point. It measures 8.5 cm in length.

 

On the way back, we kept our eyes peeled for anything we may have missed. I was sifting random spots of gravel, but not having the most luck. Lari casually handed me rock with a pearly white exterior and triangular shape. It was the most textbook mastodon I had ever seen, but she wasn't very impressed with it. She told me she had many of these already and that nonmarine fossils didn't interest her. I won't say I understand her terrestrial prejudice, but I will withhold my complaints since it meant I had acquired my first significant chunk of proboscidean .  

 

Mastodon enamel, mammoth enamel, and vole tooth.

 

We finally reached Cole at the entrance. In our absence he had wondered off the other way and found a neat spider to pique his entomology interests and pocketed a few fossils. We managed to make it out by the mid afternoon, but I was so exhausted and content, I couldn't bother checking out any other spots along the river. The spoils of the hunt were amazing, but most of all I was happy to finally experience a classic hunt on the NSR as I had seen so many post about before. Doing it with a couple of friends made the adventure even better! Sadly this place has got not much time remaining, so those of you who have stumbled upon this post, maybe take it as a sign to give this historic spot one last go before the opportunity floats away.

 

Thanks for reading!

 

 

Edited March 8, 2023 by EPIKLULSXDDDDD
Spelling

[Jared C]

Awesome report, those are some fantastic finds

 

1 hour ago, EPIKLULSXDDDDD said:

I wonder if they directly competed Ptychodus out of existence or if Ptychodus went extinct on its own and mosasaurs simply filled in the niche .

IMO, Globidens evolved to fill the niche. Globidens is most classically a Maastrichtian animal, and their occurrence in the Ozan formation is only a somewhat recent development. Mike Polcyn had some early involvement on the Ozan Globidens. Thus, middle campanian Globidens are unusual and likely basal to the group (though IMO those teeth look pretty derived to me).

 

Ptychodus as a genus really started diminishing after the Coniacian and sputtered its last breaths (or bubbles, hehe) during the early campanian. Not entirely sure why. Maybe our resident Ptychodus expert @LSCHNELLE has some insight. 

[Jared C]

1 hour ago, EPIKLULSXDDDDD said:

Darl or Hoxie point. It measures 8.5 cm in length.

Also, I'm not strong in arch at all but I would agree with Hoxie. I have seen a very similar Hoxie (also while hunting the Ozan formation, lol)

[Mikrogeophagus]

34 minutes ago, Jared C said:

IMO, Globidens evolved to fill the niche. Globidens is most classically a Maastrichtian animal, and their occurrence in the Ozan formation is only a somewhat recent development. Mike Polcyn had some early involvement on the Ozan Globidens. Thus, middle campanian Globidens are unusual and likely basal to the group (though IMO those teeth look pretty derived to me).

I will say that I did read on the Oceans of Kansas site that Globidens alabamaensis is the oldest in the literature coming from the Early Campanian. That would place it pretty close temporally with the youngest ptychodus from the Roxton Limestone of the Gober Chalk (also Early Campanian). But definitely agree ptychodus seemed to be already well on its way out by the time Globidens appeared. Fun to wonder about.

 

 

[Doctor Mud]

Great trip report. Loved that Ischyrhiza mira tooth. Haven’t heard of that before - is it reptile or fish?

 

Wish we could find Squalicorax teeth here, I’m a sucker for anything with serrations! Wikipedia says you can find them in NZ but the article has no references. @Al Dente might know? 
 

How awesome that you can also find artifacts there too.

 

 

Edited March 8, 2023 by Doctor Mud

[Mikrogeophagus]

24 minutes ago, Doctor Mud said:

Loved that Ischyrhiza mira tooth. Haven’t heard of that before - is it reptile or fish?

It's a rostral tooth to a sawfish (the tooth on the saw itself)!

[Al Dente]

6 hours ago, EPIKLULSXDDDDD said:

This is a fragment of a hybodont spine! I wish I could pin down a more specific ID, but the info on them seems limited. I will say that, out of Moss Creek, I had found a tooth belonging to Lonchidion babulskii last year which could be the culprit. Quite an uncommon find for the NSR! Wondering if any shark experts here might have any ideas @ThePhysicist@Al Dente. 

Chimaera is another possibility. Something similar to Ischyodus.

[Jared C]

5 hours ago, Doctor Mud said:

Wish we could find Squalicorax teeth here, I’m a sucker for anything with serrations! Wikipedia says you can find them in NZ but the article has no references. @Al Dente might know?

there's some end cretaceous marine stuff there. Check out this link about NZ mosasaurs, the formations that produce them will probably also produce Squalicorax.

https://www.otago.ac.nz/geology/research/paleontology/otago065923.html#:~:text=Mosasaurs have been found previously,Cretaceous reptiles in New Zealand.

[Doctor Mud]

3 minutes ago, Jared C said:

there's some end cretaceous marine stuff there. Check out this link about NZ mosasaurs, the formations that produce them will probably also produce Squalicorax.

https://www.otago.ac.nz/geology/research/paleontology/otago065923.html#:~:text=Mosasaurs have been found previously,Cretaceous reptiles in New Zealand.

Thanks @Jared C!

 

Ive been collecting a site with abundant Mosasaur, plesiosaur bone etc near me and there are loads of shark teeth, but alas no Squalicorax. It’s supposed to be global so surely it must show up. Maybe there’s something about the deposits I’m collecting that is not a suitable environment?

 

I haven’t heard of anyone who’s collected one in NZ and I haven’t found it in a paper. 

 

I’ll keep on looking though! 

 

thanks for the reference. 

[MarcoSr]

2 hours ago, Al Dente said:

Chimaera is another possibility. Something similar to Ischyodus.

 

I agree with Eric.  Below is a Chimaera fin spine, from my collection, from the Paleocene Aquia Formation of Maryland.

 

 

 

 

 

 

 

Marco Sr.

[Al Dente]

7 hours ago, Doctor Mud said:

Wish we could find Squalicorax teeth here, I’m a sucker for anything with serrations! Wikipedia says you can find them in NZ but the article has no references. @Al Dente might know? 

 

I did a Google Scholar search and couldn't find an example of Squalicorax from NZ. 

[Doctor Mud]

9 minutes ago, Al Dente said:

 

I did a Google Scholar search and couldn't find an example of Squalicorax from NZ. 

I couldn’t either. The Wikipedia article I read that said they had been found in NZ didn’t have citations, but cited Capetta’s work at the end. 
 

[PaleoPastels]

So happy you had so much fun! You left out the part where we were wading in waist deep water and my Icelandic slipped out happily when the soft-shelled turtle popped up in the water next to us! That was such a treat! Also the 85° angle cliff I scaled in flip flops was fun.  
 

I agree with Tylosaurus proriger as I said for the first/big tooth specifically- the apical ridge design and overall compressed mosasaur tooth with the pronounced anterior carina are dead giveaways as I have a few Tylo’s myself! 
 

It’s most likely a Globidens alabamensis tooth cap btw; the most recorded species of the area.   

 

Also no shade for anyone who loves mammal fossils! When you dream of wanting a double major in marine biology and paleontology for Mesozoic marine fauna you gotta save pack space to pick up your own study materials! I’ll save any masto teeth fragments for ya- I’ve already got a goodie bag going for next time.   
 

Thanks again for coming out- one of the best hunts EVER! Hopefully you didn’t get too much sun! 
 

I felt like my old forum pal Fruitbat was watching over us that day.  The weather was so perfect!

 

Extra in-situ pics from that day because that’s what people here wanna see! 

 

 

 

 






 



 






 


 



 


 


 



 



 



 



 



 



 



 



 



Curious to know what this is actually! Looks like marine reptile material but the texture is telling me it’s something else! 
 

EPIK came over and plopped this in my hand and asked, “Hey Larí, is this a globidens?” and of course I squealed in celebration for him!







***So my best bro Cole actually found an impressive Encho fang! I’ll try add a pic later (I’m out camping for morel season atm.) Maybe if he wasn’t talking to his girlfriend on the phone he’d find more stuff!    Happy he found a cool Latrodectus to entertain him! Sadly he didn’t take a picture. 

Overall I’m happy EPIK found the coolest stuff since he traveled so far!  I came home with a heavy fanny pack of giant verts but he arguably found some of the coolest treasures I’ve seen in a day trip. Thanks again for hanging out & splashing in the river with me, we gotta do that again sometime at another favorite spot. 
 

Edited March 8, 2023 by PaleoPastels
more pictures!

[automech]

@EPIKLULSXDDDDD "Sadly this place has got not much time remaining, so those of you who have stumbled upon this post, maybe take it as a sign to give this historic spot one last go before the opportunity floats away." 

 

 

I don't understand? What's happening to that area?

[digit]

Spectacular trip report replete with lots of great imagery. You can't beat a collecting trip to a classic locality--unless you add in some additional forum members as collecting partners.

 

Thanks for taking us along vicariously on this trip.

 

 

Cheers.

 

-Ken

[Collector9658]

1 hour ago, automech said:

@EPIKLULSXDDDDD "Sadly this place has got not much time remaining, so those of you who have stumbled upon this post, maybe take it as a sign to give this historic spot one last go before the opportunity floats away." 

I don't understand? What's happening to that area?

Dam construction.

Edited March 8, 2023 by Collector9658

[ClearLake]

1 hour ago, automech said:

I don't understand? What's happening to that area?

They are constructing a dam just downstream of the prime fossil hunting areas which, when complete in a year or so, will flood the whole area.  People need water, and the area's population is rapidly expanding.

[ClearLake]

@EPIKLULSXDDDDD, great trip report, glad you found some great items and had a good time.

[Advantage]

Thanks for taking time to write and share the trip. I loved reading it and wonderful collecting.

[Jared C]

Speaking of hybodont spines, take a look at this campanian specimen @Mtskinner found in Alabama. It is truly spectacular 

 

 

 

[Mikrogeophagus]

@Al Dente @MarcoSr I had no idea chimaeras also had fin spines! I think you two are on the money. Looks like a closer match than hybodont.

[LSCHNELLE]

23 hours ago, Jared C said:

Awesome report, those are some fantastic finds

 

IMO, Globidens evolved to fill the niche. Globidens is most classically a Maastrichtian animal, and their occurrence in the Ozan formation is only a somewhat recent development. Mike Polcyn had some early involvement on the Ozan Globidens. Thus, middle campanian Globidens are unusual and likely basal to the group (though IMO those teeth look pretty derived to me).

 

Ptychodus as a genus really started diminishing after the Coniacian and sputtered its last breaths (or bubbles, hehe) during the early campanian. Not entirely sure why. Maybe our resident Ptychodus expert @LSCHNELLE has some insight. 

I have not studied what led to the demise of Ptychodus. Shawn Hamm ponders that question near the end of NMMNH Bulletin 81. I think he says that part of it's demise may have had to do with changing ocean conditions within the Western Interior Seaway (WIS) and other areas around the world. He points out that they were a diversified species adapting both low crown broader teeth (marginalis, decurrens, latissimus, martini, polygyrus) and narrower or conical higher-crowned teeth (anonymous, occidentalis, whipplei, mortoni, atcoensis, rugosus) to hunt different species of shellfish - not only bottom-dwelling ones. He thinks some post-Turonian Ptychodus could swim as fast as some of the laminiform sharks like Cretoxyrhina, Squalicorax and Cretalamna. Also, he thinks that predators like the mosasaur and other creatures may have preyed on them as the size of the WIS diminished. Then, other shell-crushing competitors like skates, rays, and Globidens seem to have filled in the niche that Ptychodus left behind.