Hell Creek Gar Reproduction Now Available

ValDaGar in initial stages of preparation

Back in the summer of 2012, known as the summer of "Lake Dakota" in the lab due to how much it rained that year keeping us at our soggy campsite, I was lucky enough to discover an articulated gar in the Hell Creek Formation. In the previous decade of Hell Creek fieldwork, I had found hundreds of scales and isolated bones from gar but hadn't given them much thought. 

Hell Creek gar scales

Perhaps it was because of all the rain that year, but late on our first trip out to South Dakota for that season on a low, soft, sandy outcrop I found vertebrae, articulated scales and the outline of a skull just beginning to erode out. I had no idea at the time just how special that discovery would be. It turns out this specimen - RMDRC 12-008 - which I nicknamed "ValDaGar" after my wife giving it a bit of Nordic sounding flair, was the most complete articulated gar fossil out of the entire Mesozoic of North America. 

RMDRC 12-008 ValDaGar as originally found, with beautiful articulated scales

The excavation was pretty straightforward. Our now Executive VP Jacob Jett and I managed to perimeter around the specimen through the soft sand and jacketed the gar all in one day. Unfortunately there were no sizeable outcrops immediately adjacent to the dig to help place us in section, however a butte a short distance away had a Triceratops skeleton eroding out approximately 60 feet above our dig, indicating we were definitely working on a Cretaceous gar, not a later one from the post-asteroid Fort Union Formation. 

Jacob Jett cleaning out the trench before jacketing

I'm not going to lie, I was a bit nervous when it came time to prepare the specimen. The matrix was very soft, which poses quite a few challenges, especially when you're set to work on an animal that is basically a tube sock made of 10,000 scales floating in loose formation in the sand. Since this specimen was extremely rare and scientifically important, I went very slowly.

Initial prep of the skull area in the lab

Much of the initial work was done with just an X-acto knife and chip brushes, slowly working down to the specimen until you feel and hear the "thunk" of the underlying bone or scale. Once the bulk of the matrix was moved off a section, I stabilized it with Paraloid B72 and came back with low pressure air abrasion to finish cleaning the surface. All this was done one section at a time so that the air abrasion wouldn't blow away any adjacent patch of scales that may not have been consolidated yet. 

Skull area after basic consolidation and air abrasion

In the end, prep took me about a solid week. After the specimen was cleaned, we wondered how to replicate this rare (and likely new taxon) gar. Traditional silicone molding techniques were rejected right away due to the danger the demolding process might pose to such a soft and delicate specimen. It would be a shame to rip it apart after all of this work so we turned to technology.

Skeleton after prep, Senior Curator for scale

We were curious how the specimen looked hidden under the surface of scales and sand, and what might be present for the lower jaws that were spun under the skull. For this we took it to a local animal hospital, Powers Pet Emergency in Colorado springs to have it CT scanned in between patients. There were concerns that the metal poles used in stabilizing the field jacket might interfere with the scans however no problems were noted and the images they turned out just fine. 

Image taken of the skull area at Powers Pet Emergency

Luckily though 3d scanning was very much still in its infancy at the time, we at TPI had the equipment and skill to create a very high fidelity surface scan and model of ValDaGar. Turning the digital model into something physical would take a bit more time though, as we thought the resolution of the printers used in making such a large print was insufficient for what we wanted the final product to be. Fast forward about a decade. Luckily for us, technology has caught up enough to allow a high fidelity physical replica to be made. 

Scanning of ValDaGar in our collections area

We were able to print it out, though not all in one piece. That's where I came in, reassembling the parts and getting it ready for our skilled artists to detail and paint up. The detail was fantastic, especially with the diamond plate skin resolution.

With this step finished, we are now able to offer reproductions of this Mesozoic gar for museums across the world. Contact Jacob Jett jacob@rmdrc.com for specifics and to make your order.

What's the Bag Limit on Xiphactinus?

October has a lot of opportunities for hunting big game such as deer and elk. Some people use muzzleloader firearms or bows and arrows. I prefer to use my trusty walking shovel, Winona.

Fishing for the biggest toothiest one out there

This October I led a small field crew out to the Niobrara Chalk of Western Kansas, squeezing a week of scouting in between seminars and the Society of Vertebrate Paleontology meeting in Minneapolis. Due to injury, this was my first time out on the rocks since August. The Kansas chalk is full of some amazing fossils like Pteranodon, Tylosaurus, and my personal favorite, Martinichthys. It also has Xiphactinus.

Finding a piece of Bonnerichthys while wearing a Bonnerichthys shirt

By Wednesday morning of the trip, we had found a few cool specimens like a pathological tail fin from an ichthyodectid fish, but nothing large or truly impressive. As my crew packed up some of their gear at the truck, I struck out for a distant outcrop that I could see the distinctive Marker Unit 5 layer (home to Martinichthys). Less than half of the way there, I looked down and froze.

Fish face as found, curatorial hand for scale

Eroding out of the small exposure of chalk is the perfectly articulated face and pectoral fin of a moderate sized Xiphactinus. The amazing thing is the up side of the fossil was all still articulated. Usually when the animal decays on the seafloor, the top side gets stirred around a bit by scavengers. The bottom part, pressed into the seafloor ooze, is usually even better.

Evan and Jordan opening the site to see what's there

Before touching it I grabbed the team. They were from our 3D department and were getting some well deserved away-from-screen time. This past year I worked with them on so many excellent dinosaur, mosasaur and crocodilian reconstructions that some fresh air and exercise seemed like a great respite. And what better way to get fresh air and exercise than with digging up a giant fish? I told them I found another Xiphactinus and they only groaned a little. When they got to the untouched site, I think they got a little excited. It's not every day you have the chance to work on a beautiful fossil like this one.

Undercutting process begins

When you're big and dead and bloated floating at the surface of the Western Interior Seaway, you make a really nice meal for all kinds of predators in the late Cretaceous. After a little excavation (the site had maybe 3 inches of overburden on it), we determined that all that remained of this fish was the disembodied head, fins, and a few vertebrae. The rest of the fish was long ago consumed by some lucky shark I think. That made our jacketing job so much easier, as this was originally a 12 foot long fish.

The jacket is finished!

I was very nervous about the flip of this large jacket in very loose and friable chalk. I broke out every trick I could think of to ensure success but the lift and flip was extremely stressful. Luckily, 27 years of experience paid off and the flip went perfectly! We lightened the jacket by removing a little of the extra chalk, then loaded it into the back of the field truck to bring back to Colorado. The naming scheme this year is due to a song I had stuck in my head, so they all flow from a stream of consciousness rant during the song "A Shogun Named Marcus" by the band Clutch. This being the 4th good fish I found this year, it gets the name "Spitfire", which I think suits it just fine.

I managed to get 2.5 out of the 3 of us in this shot. Successful flip!

All in all, it was a very successful expedition to the Niobrara. No pterosaurs or giant lizards, but a big fish head and another specimen worthy of publication is still a good haul. Stay tuned for more updates as we get to preparing Spitfire's fish face back in the lab. 

Ashley: The cannibal Xiphactinus

 If you're following me on the twitters I'm sure you all know about my absolute and undying love for the giant ugly predatory fish from Kansas, Xiphactinus audax. We spend a lot of time in normal years in Kansas during the spring and fall (when the weather and bugs aren't too miserable) and we tend to find a good number of at least partial skeletons, some exceeding 18 feet in length.

Random Xiphactinus verts in the wild

It's easy to think of them as just another boring fossil, as if they were the hadrosaurs of the ocean, but every once in a while something about them makes them interesting.Sometimes because they are found inside something interesting, other times because something interesting is found in them.

Xiphactinus as stomach contents of a large shark, Cretoxyrhina
Photo taken at University of Kansas Natural History Museum

Xiphactinus is well know for its gluttony. The famous "Fish Within a Fish" at the Sternberg Museum of Natural History, where a 13 foot long Xiphactinus semi-successfully ingested a nearly 6 foot long Gillicus is a prime example of this. I claim it to be semi-successful as the Gillicus is completely articulated and not digested, indicating that trying to swallow this meal likely killed the Xiphactinus. Other times smaller remains of a fishy meal in the body cavity of a Xiphactinus are found, we see this in a little less than half of our specimens.

Photo courtesy of Mike Everhart www.oceansofkansas.com

Fast forward to the spring of 2018. I was scouting the lower Niobrara Chalk in Gove County, Kansas. The chalk is defined stratigraphically by 23 distinctive easily traced (usually) bentonite layers laid out by Hattin in his 1982 work. These outcrops were around Hattin's Marker Unit 6, so the upper limit of where I could possibly find my dream fish , an articulated specimen of the ram-snouted Martinichthys ziphoides. No luck on that front however I did find this fine pile of bone eroding out, seemingly face-first. A small pile of bones is always a good sign!

The bones are the kinda grey things on the yellow chalk

Unfortunately it looked like it was headed into the base of a big cliff. After initial evaluation, we decided to GPS and cover up the site to protect it until we could come back at a later date. That date came the next spring.After a long morning of removing overbruden, we were relieved to see the fish had actually folded in half back on itself about 4 feet from the erosional edge and the balk half pointed back out that direction. We didn't have a tail fin, but we also didn't have to move a mountain of rock chasing this Xiphactinus either. I gave it the nickname "Ashley" after one of my trivia teammates (remember when we could go to bars and do that? Wear a mask and maybe we can soon).

Can you see the digsite?

One of the strange things we noticed while exposing the bones in the field was a large bulky bone near the belly. It looked like a cliethrum, one of the bones that the pectoral fin hangs off of. The skeleton itself was mildly disarticulated in parts, and any Xiphactinus will have 2 of them, so maybe this was just a bit of Ashley that was pulled off the carcass when scavengers like the shark Squalicorax came to strip off all the flesh.

Typical Kansas fish dig

Preparation showed the skeleton was in much better condition than we had imagines, with decent articulation and a beautiful pelvic fin. It also showed both cliethra that were supposed to be present on a Xiphactinus wee in fact there in place. So what does that mean with our now THIRD cliethrum?

2 very nice looking jackets all cleaned up

One way to be sure is to prepare it as well. Free from all of its matrix two things were readily apparent: One: the acid-etched texture of the surface of the bone meaning it was stomach contents and Two: based on the shape, it also belonged to Xiphactinus.

The smoking gun, so to speak. Acid-etched Xiphactinus cliethrum

With that shocking knowledge in hand with al of the bad things Xiphactinus could be (common, boring ugly, a lot of work to dig up and prepare) we can also add cannibalism to that ever growing list.

Protosphyraena: Like a Swordfish Made Babies With a Chainsaw

We're back from SVP 2017 in Calgary, which was an awesome opportunity to debut our prototype Protosphyraena (Proto Proto) skeletal reconstruction. I've been involved with this project for 13 years now, very heavily for the past 4 with my various research projects with Drs. Jeff Liston, Kenshu Shimada, Bruce Schumacher and Matt Friedman. We've published a bunch of papers and talks recently, and there's even more on deck. If you're in Tahiti next week, stop by and hear my talk!

Image Copyright Mike Everhart

Loomis' reconstruction attempt

Protosphyraena was a tough nut to crack. The first bits were discovered in the late 1700s in the English chalk and first figured by Gideon Mantell in 1822. It got its name later in the mid 19th Century by Joseph Leidy meaning "early barracuda" due to the flat knife blade shaped teeth. Unfortunately this is what happens when you only have sparse material to work with. Protosphyraena is known now to have a basically worldwide distribution however since the animal has replaced its skeletal bone with cartilage wherever possible, more than isolated bits are extremely difficult to come by. In the Bone Wars of the late 1800s, Cope and Marsh's teams discovered many partial specimens in the Niobrara Chalk of Western Kansas, consisting mostly of isolated pectoral fins and skull bits.

Pectoral of P. perniciosa showing saw-tooth edge

The skull was amazing, with a long rostrum and forward-directed massive protruding teeth. The fins showed some variation, however the ones attributed to Protosphyraena perniciosa reached nearly a meter in length ad were adorned with saw-like serrated front edges. A tail fin was discovered near the turn of the last century and then one the first reconstructions was attempted by Loomis.

Cast and original parts at beginning, apple for scale

Not too shabby based on what they knew. Since the body had such little bone, it was highly unlikely that one would be found, yet the Niobrara as usual was full of surprises. In 2003 Mike Triebold found a partial Protosphyraena skull eroding out of the rocks in western Kansas. The specimen was already missing its rostrum, but a bit of pectoral fin was also visible. He continued excavation and noticed articulated evenly spaced spines, and followed them. They were ribs, hemals and neurals, ans they led to an articulated tail. This was the first "complete" Protosphyraena discovered.

Dig site pic, the specimen is already uncovered and pedestalled

This specimen ended up becoming the "Rosetta Stone" for our reconstruction attempt. Though it was a small example, it gave us tons of information about the body proportions. it kept on giving though, showing the streamer-like pelvic fins and large lobe-shaped "go faster" caudal peduncles.

The "go faster" caudal peduncles

We prepared out several specimens of large Protosphyraena in order to have a decent starting point for the reconstruction. One good skull specimen was partially disarticulated, we scanned the gill basket of a second smaller one and reproduced it out at the proper size on our 3D printing rigs. Our pectoral fin donor specimen was famously covered here as the victim of a poaching attempt in 2011. The original bones were molded and we made multiple copies of the parts so we could cut them up into individual elements. They were later remolded with most of the distortion taken out.

The kid seems bored

Jaws attached

Complete skull exterior

After that, the process was pretty easy! We decided to ignore how bizarre the critter was and just accept that's how these parts fit together, seeing where the reconstruction took us. It tuned out to be stranger than we ever imagined, and a lot bigger too, measuring over 2 meters in length (and flipperspan). We showed it off in Canada and it seemed to be a big hit! Enjoy the photos of the finished mount below.

I'm useful as a scalebar sometimes

Down the hatch!

Front view

First Kansas Trip in the Bag - 2017

For the first time in a few years, we've been able to hit the Niobrara outcrops in the spring! Holy crap was it cold. The last day out, I don't think it got above 50 degrees, not that the 40mph winds would make it feel any warmer. Perfectly miserable. And just like clockwork, on our last day, as the sun was setting behind a large row of thunderstorms on the horizon, we found the best skeleton of the trip! The rest of the time was staring at blank ground finding fossil poop.

Look at this swirly poop!

I entertained myself by finding a "nice" Xiphactinus tail. I was instructing a new hire on how to actually find fossils in pretty bleak badlands when I saw just a small fragment of tail fin coming out of the rock. I'm happy I found this one as since we have SO MANY Xiphactinus specimens in storage, we've implemented a "one in, one out" policy on these fish and I've somewhat jokingly insinuated firing anyone that finds another of these darn fish. Our newbies were safe.

Well, there's a fish tail

Jesse using a chainsaw to trench around the fossil

When you find weathered out fish tail chunks, you have to chase them in (even if they're "just" a Xiphactinus). Sometimes the rest of the tail is there. Sometimes there's the rest of a 15 foot long fish attached to it. Sometimes it just ends. In this case, we found a perfect lower lobe of the fin, but no body. As far as we were from the truck, I'm happy we didn't have to make a huge jacket, since those are heavy and I'm getting lazy in my old age.

Trenching complete, curatorial boot for scale

Jacketing complete and ready to flip, other curatorial boot for scale

Popping it out and prepping it was also quick. Measuring the vertebrae we found it's the exact same size to complete another Xiphactinus specimen we excavated 3 years ago (which just happened to be missing the tail). This will help us out tremendously when we panel mount the animal in the near future.

Not too shabby!

Other stuff was less plentiful on this first trip, but we were lucky enough to find parts of 3 sea turtles, which is always really nice.

Jesse and grace entrusted with power tools to get to a turtle

And of course at the very last minute, Jesse stumbled on a pretty complete Clidastes skull in an outcrop near where we discovered our gigantic 17 foot Xiphactinus specimen 20 years ago. We worked very hard to excavate the specimen with daylight fading and weather bearing down on us.

Jesse and grace getting Clidastes block ready for jacketing

The specimen was safely loaded in the truck by headlight, which also made for a really interesting drive through farm fields in the dark at the end of a 14 hour day. Prep is going on right now, so stay tuned to see how this cute little mosasaur turns out!

The Accidental Ichthyornis

Field identifications are problematic.

In mid October of this year the weather in Kansas was still warm enough to extend our dig season. That trip was pretty successful, finding a back half of a Protosphyraena and several small fish. Early on, Mike even thought he found another Pteranodon leg.

The drive to the site is a lot tougher when you can't see landmarks

We came out early in the morning. Man was it foggy. The entire day was supposed to be dedicated to finishing up excavation at several small sites. Since the "Pteranodon leg" site was so small, Mike and Jacob spearheaded the excavation there, while I wandered off to collect a Cimolichthys head and isolated Ichthyodectes site.

Several bones coming out at the site as discovered. Definitely not fish.

The "Pteranodon leg" showed some promising chunks of bone coming out, however inspection as they got down to the bone layer showed not a whole lot was there. Not like the large bones we were hoping to find for a Pterosaur.

That's a big hole for such a little block

Not a huge worry though, we perimeter the sites and very rarely expose the bone in the field, we will just find out what the "Pteranodon leg" looks like when we get back to the lab.

Jacob jackets and despairs as I tell him we have to go dig up another fish

Looking back at the video, just as Jacob began jacketing the specimen, I show up back at the site proudly announcing the discovery of the "Nia" Xiphactinus site that I blogged about last time. We all decided to drive over to the big fish and start work as the jacket cured. We were so stoked about the big fish that it was about a month later when we finally asked ourselves "Hey! Where did that jacket go?"

Turns out, we left it sitting there in the field, right next to a regularly visited oil well. Whoops! Over Christmas, Mike returned to the site to see if someone had poached it. Nope, the jacket was still exactly where we had left it. I guess you can say we got dang lucky. Let's never do that again.

Mike pulled it out and brought it back to the lab, where it sat for a week as I let it dry out (dry chalk behaves better than wet stuff when prepping, especially with small fossils). That's when the Eureka Moment happened: prepping down on the "Pteranodon leg" things weren't looking right. I immediately switched to my microscope, pin vise and very low pressure air abrasion (about 3psi with sodium bicarbonate blast media). My suspicions on the specimen's identity were confirmed when I found teeth. Pteranodon doesn't have teeth, but there's one small thing in the chalk with reptile-textured bone that does have it: a bird! Not only was it a bird, but the only complete articulated skull of Ichthyornis, who had been found only in fairly incomplete form since Marsh's days in the 1870s. This accidental and overlooked jacket suddenly turned into one of the rarest finds in the entire 160 year history of fossil hunting in the Niobrara.

Bird teeth, just a few milimeters long

Stay tuned for project updates as we work on this spectacular fossil.