Partial Mosasaur skeleton - central texas

[Jared C]

Last weekend was one I'll never forget... I've barely processed it, but now that I can be more coherent, here is the story of the mosasaur we found 

 

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On September 11 & 12, I researched and found new fossil hunting area (to me), that exposed the Eagle Ford formation. I decided to scout it, and that scouting trip ended up being wildly successful. On the first weekend of my scout, I walked away with several ptychodus teeth, a great squalicorax, and two small mosasaur teeth, all still in matrix. Many of the ptychodus teeth here represent a species that will be described next year by Shawn Hamm, and are similar to Ptychodus anonymous.

(Below - one of the teeth from the scout - this tooth is one from the Ptychodus species that will be described next year)

 

Fast forward a week. It's Friday, September 17. I returned to my new honey hole a second time, intent to explore a little more. The spot I was working on the week before produced more ptychodus, fish bones, and fish teeth. It was fantastic, and I decided to keep a keener eye out for a different spot to work on next (still in the same area).

 

Walking back, I spotted a great exposure of dense shell hash, at the bottom of the creek. The barren, blueish layer of shale that usually covers this hash had lifted up in one big slab, probably with a flood, and revealed the nice patch I was looking at now. Feeling pretty lucky, I sat down and got to work. "This is the spot to spend the rest of my time here on", I decided.

 

I got to work lifting slabs, expanding the exposed patch, and had some nice results. More Ptychodus teeth, and the odd Scapanorynchus tooth revealed themselves. One slab had a little ptychodus on it that I popped loose with my finger. Immediately below it sat another tooth, in the same orientation that it would be as part of a mouth plate. That was crazy! Perhaps I have a partial mouth plate on my hands (spoiler alert - I still need to prep it to find out)

 

By now, it was late afternoon, and the day flew by. I suddenly had the realization that I was about to be late for work, and had to speed back. I made a mental note to come back to this excavation I had started the next day.

 

Saturday, September 18

Recently I had gotten my older step brother interested in fossil hunting. Today marked the first day he was keen enough to go on his own, rather than with me....however, I should preface this by saying he was only alone because he wanted to hunt quite early, at 8 AM.....my gears were barely even turning yet, so I told him I'll meet up with him a little later.

 

Over the phone, I told him where to go, what type of rock to investigate, and where the spot I was excavating was located. After finding the excavation I had started the day before, he sat down to continue my work until I got there.

 

As he told it to me later, he picked around in the rubble I had left the day before, to see if I missed anything, and then got bored and decided to lift the next loose looking slab...and BAM, he was met with bones. Once I picked up the phone, I was off like a shot.

 

Upon arrival, I immediately realized that we were out of our depth, as it seemed like the bone continued further on under the slabs. Before we even touched them, I hastily contacted @JohnJ, since I had no idea what to do next. He couldn't be there due to a commitment, but the advice he gave to us about continuing the excavation gave us enough confidence at least start. Throughout this dig, John was the crutch that made the whole endeavor manageable - without him we would've been completely lost.

 

(Here's what we saw, before any excavation)

 

 

One Walmart run later, and we got to work. The rock quality wasn't great, and crumbled easily. We worked carefully, but soon had to learn to deal with the fact that some bones would break in the condition they were in. Nothing glue couldn't fix later.

 

(what we saw after the bones had a chance to dry a little, and after some excavation)

 

At this point, we had found three associated mosasaur teeth. With the first tooth, I was hesitant to say it was associated, because there were tons of little teeth of all sorts around. A second, much smaller tooth made me reconsider. 

(Below, the third associated tooth)

It's worth noting that we found quite a few Squalicorax teeth (maybe 7 or 8), and a  few Scapanorynchus teeth as well - suggesting a scavenging event. What was really bizarre though was the sheer number of little Ptychodus teeth (probably around 6 or 7), many of which were the undescribed species I mentioned earlier. While likely a coincidence, I think it's still fun to imagine this Ptychodus crushing through bone as it scavenged a skeleton - a completely different look on what Ptychodus are supposed to do as shell crushers. 

 

(Some of the shark teeth revealed though the dig)

 

 

(Smacking a hammer around doesn't always go as planned)

 

 

At the end of day one, we had lifted one slab out. It was when we tried to reduce some excess rock at the side of said slab that we found the craziest part yet....a jaw piece! The shaky photos I took of this jaw in the field aren't a great angle, so here's that same jaw piece at home:

 

 

Only a little bit of bone remained poking out of the bank after day 1. So, we thought day 2 would go by quickly... but once we started excavating those little pieces, more revealed itself.

 

 

This slab was particularly unstable, and after four hours of careful digging, we decided to rip the band aid off and try to pry it out.Fortunately, instead of coming apart in 20 pieces, it came apart in just 2

 

(below: One of the two slab pieces)

 

We were done-  9 hours of excavation for what felt like (after the fact) a small amount of bone. However, since so much bone is still deep in the matrix, we're crossing our fingers that we have more than just isolated jaw elements and vertebrae.

Since both of us are new to prep, we decided to leave this intimidating (to us) job to the talents of Kris - @Ptychodus04, who graciously made room for us among his existing prep work. I'm excited to see what his hand reveals, and I'm crossing my fingers that our find has some diagnostic elements.

 

I'll likely continue to post updates on this thread as they come, but this is basically it! I'd like to write a little more, but unfortunately I have chemistry homework that simply cannot be neglected any longer... It's been understandably hard to think about those trivial things after a weekend like this 

 

[facehugger]

Pretty amazing stuff. Exploration has its benefits!!!

[JohnJ]

Again, a hearty congratulations to you and Christian!  Your mosasaur adventure and education has just begun.  

[Mainefossils]

That is a really neat find! I will look forward to seeing the post-prep photos, @Ptychodus04 always does an amazing job. Thanks for posting this! 

[Denis Arcand]

Quite an exploit, I would have liked to be there.

[Fossil_Adult]

Wow. Nice find! A partial mosasaurus skeleton must me a trip maker.

[old bones]

How exciting!

[fossilhunter21]

Awesome find! 

[Uncle Siphuncle]

You guys have essentially smoked my 18 years of Eagle Ford experience in 1 hunt!  Well done.

[Jared C]

5 minutes ago, Uncle Siphuncle said:

You guys have essentially smoked my 18 years of Eagle Ford experience in 1 hunt!  Well done.

Sheer luck, that I can promise you 

[HemiHunter]

awesome

[FranzBernhard]

WOW, simply WOW!! 

Thanks for sharing!

 

8 hours ago, Jared C said:

It's worth noting that we found quite a few Squalicorax teeth (maybe 7 or 8), and a  few Scapanorynchus teeth as well - suggesting a scavenging event. What was really bizarre though was the sheer number of little Ptychodus teeth (probably around 6 or 7), many of which were the undescribed species I mentioned earlier. While likely a coincidence, I think it's still fun to imagine this Ptychodus crushing through bone as it scavenged a skeleton - a completely different look on what Ptychodus are supposed to do as shell crushers. 

Yeah, most fun part would be to decipher the relationship between these three species. This could be a really significant contribution to science.

 

2 hours ago, Uncle Siphuncle said:

You guys have essentially smoked my 18 years of Eagle Ford experience in 1 hunt!  Well done.

 I think, this is the biggest compliment you can get, @Jared C!

 

2 hours ago, Jared C said:

Sheer luck, that I can promise you

No, no! Its all about this guy:

8 hours ago, Jared C said:

and then got bored and decided to lift the next loose looking slab...and BAM, he was met with bones.

And this:

8 hours ago, Jared C said:

he wanted to hunt quite early, at 8 AM

Exactly also my time to start with field work, latest ! (Have yet to find some Cretaceous reptile, though...)

 

Again, thanks for sharing, what a great experience, and you are only starting!

Franz Bernhard

Edited September 23, 2021 by FranzBernhard

[Jared C]

12 minutes ago, FranzBernhard said:

Yeah, most fun part would be to decipher the relationship between these three species. This could be a really significant contribution to science.

 

I really hope so... for one, the strata that we discovered this mosasaur in is 91 million years old, making it a basal species, much older than most mosasaurs. If we're lucky, it will have potential to be significant in that way 

 

Also, although Christian popped out most of the matrix shark teeth in the area before I got there (beginner's error, no biggie), I still think there are bound to be more locked in the matrix. I'm secretly really hoping there are some Ptychodus teeth in such a close association - it may be enough evidence to suggest a change in niche, or at least an opportunistic behavior in the genus- especially if similar fossils are found that show that show the same thing (sounds like a new mission....)

It's not a fully formulated thought of mine yet, but I find it easy enough to imagine. Marrow is nutritionally rich, and easy enough to harvest for a shark that likely hunted ammonites, bivalves, and perhaps even sea turtles.

I've also read that because squalicorax teeth are so commonly found among skeletons like these, it's thought that they scavenged, and this find also seems to reinforce that.

 

This Ptychodus talk kind of reminds me.... I haven' seen anything before that tries to distinguish the different feeding patterns exhibited by different ptychodus species - their teeth are so variable after all...it would be hard to convince me that peg toothed Ptychodus whipplei had the same diet as the flat toothed Ptychodus decurrens, for example. If that research doesn't already exist (I'm sure it must somewhere though), then that sounds like a fun research project to try solving on my front....just speaking to wind here, sorry for my ramblings, lol.

 

[Jared C]

7 hours ago, Fossil_teenager said:

Wow. Nice find! A partial mosasaurus skeleton must me a trip maker.

For sure! I'm lucky, as this is a less than 30 minute drive from my house. I never thought central texas had this sort of thing to offer when I started, and instead assumed that the party was all happening in north texas instead. I'm still pretty new to all this (only been seriously fossil hunting for 8 months), and I'm sure many of the members here will remember how I constantly whined about never even finding shark teeth around town. Gone are those days, but I don't think I'll beat this find soon.

[FranzBernhard]

59 minutes ago, Jared C said:

as this is a less than 30 minute drive from my house.

And judging by all those power lines, it seems to be located in a densely populated area.

 

1 hour ago, Jared C said:

instead assumed that the party was all happening in north texas instead.

The party takes place where you let it take place . You did exactly the right thing: Exploring, exploring, exploring!

 

1 hour ago, Jared C said:

I'm sure many of the members here will remember how I constantly whined about never even finding shark teeth around town. Gone are those days, but I don't think I'll beat this find soon.

Oh yeah !

 

Franz Bernhard

 

 

 

[Jared C]

10 minutes ago, FranzBernhard said:

Oh yeah !

point in case!

[Coco]

Hi,

 

Very nice adventure! I can’t wait to discover the rest !

 

Coco

[Ludwigia]

Isn't TFF a great resource?

[Yoda]

@Jared C

 

Fantastic find 

[pachy-pleuro-whatnot-odon]

 

I've said it before, but just: WOW! This is an amazing find, and I don't mind admitting that I'm quite jealous! Not much in terms of these kinds of exposures in my area unfortunately, so I depend on making long trips far away that typically result in one vertebrate find per trip (and with those taking place on average once a year, you do the math ). You guys got very, very lucky - or, may be, your hard work of exploring, exploring and exploring just paid off big time

 

I did once make a find like this, in much the same way you guys did, though. And even though I've got a background and training in archaeology, nothing really prepares you for a find like this: it's never under the perfect conditions or in the right place and always poses new challenges. Of course you'll get better at solving the issues you encounter the more often you face them, but I think that even the most experienced users on TFF will tell you every dig is unique. You definitely did the right thing in extracting it: this way there's no risk of it eroding away or getting intentionally damaged. And if you'd have left it, who knows who would've come to collect it... Also, when you extract part of such a fossil, you should extract it all. Otherwise you'll loose context. So, again, great job Christian and Jared!

 

5 hours ago, Jared C said:

I'm secretly really hoping there are some Ptychodus teeth in such a close association - it may be enough evidence to suggest a change in niche, or at least an opportunistic behavior in the genus- especially if similar fossils are found that show that show the same thing (sounds like a new mission....)

 

Keep in mind, though, that smaller and lighter-weight fossils have a tendency to accumulate next to bigger ones, so that finding Ptychodus-teeth next to the skeletal material may just be the effects of water currents collecting material, rather than actual evidence of feeding behaviour. You see it a lot at sites like Lyme Regis, where you get beautiful specimens of tiny ammonites laid down right next to fossilised wood. And I've seen this pattern at other sites too...

 

Let me also tag @Praefectus. May be he's got some ideas on whether this could be a russellosaurine or rather basal mosasaurine

Edited September 23, 2021 by pachy-pleuro-whatnot-odon

[NSRhunter]

Congrats man Well done

[Paleorunner]

This is a fantastic find ... 
Congratulations !!! 

[Ptychodus04]

Great trip report @Jared C

 

I’m looking forward to attacking this prep! Should be pretty cool.

[erose]

Jared,

 

Well now I want kick myself for not meeting up that weekend after you contacted John and me.  But honestly JohnJ was the man from whom you needed advice. He has experience with mosasaur fossils, and other vertebrates, that I don't.  But it's been a real pleasure following your progression here in Austin.  And an early mosasaur will definitely be an important specimen.  And again John certainly has much experience working with paleontologists and can give you serious advice on how to move forward.

 

Great big congratulations!  

 

ERose

[truceburner]

Nice work, champ! Congrats on an exceptional find.