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. 

Reconstructing Chelosphargis: What to do with a pile of bones

We spend a lot of time in Kansas hunting for specimens in the Niobrara chalk. A whole lot of time. Luckily the soft chalk erodes pretty quickly so we also find a whole lot of stuff. Occasionally though, other people also get lucky and we'll happily take the specimen off their hands. In early 2015 this exact scenario played out. You may have seen the result at our display booth at SVP this year in Salt Lake City, overshadowed by our exciting mount of our Daspletosaurus "Pete III"

Curator shadow selfie while digging in Kansas recently

A poorly collected turtle specimen from the chalk was being shown around looking for a buyer, While the collection techniques caused some damage to the fossil, it was plain to see a fairly complete tiny Protostegid was encased in the slabs of yellow rock.

So, this is how we got it. Clearly not how we would collect a specimen.

Most importantly, almost all of the skull was there, which is really nice. We immediately acquired the specimen and prepared the parts. Quickly it became evident we had a older subadult specimen of the relatively rare taxon Chelosphargis advena, an 84 million year old relative of the much larger Protostega and Archelon.

The parts after prep

Skull partway through prep

As you can see, most of the animal was there, in fact it's one of the most complete Chelosphargis specimens ever discovered. But what do you do with a pile of bones once they're all prepared? We're one of the few places with the knowledge, experience and capability to do a complete cast restoration without damaging the original bones. The first step was to mold everything as-is, so we can have parts (sometimes even multiples) to work with.

Cast skull copies getting cut and shaped to take out distortion

Distortion is taken out of the plastic and missing parts are either fabricated from similar ones from this animal, scanned in and resized from other specimens, or in rare cases done the old way with sculpting from reference material.

Carapace getting parts added and completed

The restored parts are then molded again in units so that we can make our final copy and offer it to museums and the general public as a highly detailed cast skeletal mount, perfect for display anywhere. The entire project only takes a few weeks, but the result is pretty phenomenal!

Final product!

Our Xiphactinus dig featured on River Monsters: backstory

I really hope everyone got a chance to see the River Monsters season finale. Here's a teaser of Jeremy Wade Sharing a bit of what he had learned with us in the field digging up a Xiphactinus audax skeleton.

One of the things he alludes to has a funny backstory. When we first arrived at the site, the film crew's rental minivans couldn't get near where all the equipment needed to be. Not a huge problem, we transferred it to the bed of the bosses truck and away went the gear and most of the crew. I had been riding in vehicles way too much already that morning and decided I'd walk the easy 1/4 mile or so left to the site. Jeremy, the director and an assistant decided this was a good idea as well, so I was able to show them some things in the chalk on the way up. Mostly clams. Lots and lots of clams.

The site is on the opposite side of the butte in the background

Arriving near the digsite site, literally within 4 feet of where the boss parked the truck, while talking to Jeremy about how you have to be in the right place at the right time to find a specimen, I look down and see the face of a newly eroding Xiphactinus specimen poking out of the rock. I COULD NOT HAVE PLANNED IT BETTER. It's really not all that great, but our guests had never seen the discovery of a fossil before, and they seemed pretty thrilled about it. Happy I could oblige.

Can you see it? It's a beauty!

Back in the lab the next day we worked hard to begin the prep on the Xiphactinus specimen RMDRC 14-012, which we nicknamed "Jeremy". Unfortunately, all of that seems to have ended up on the cutting room floor.

Just a few people watching over my shoulder as I prep

Nevertheless, we went ahead and finished prep on "Jeremy". Not the prettiest one, and for the life of me I can't figure out how the face was nicely articulated but the entire braincase was spun off and away. Them's the breaks I guess. As for working with the River Monsters crew again? Name the time and place, they were superb.

I've seen worse

Sclerotics in place still!

No love for Ichthyodectes?

It seems like nearly every year a new book, film, or television program comes out featuring the long-dead seaway that covered most of the central part of North America back in the late Cretaceous. Invariably they have cameos featuring Xiphactinus, Cretoxyrhina, Protosphyraena, and even the "bait fish" Gillicus and Enchodus. They have mosasaurs, pterosaurs and even sea turtles. If you didn't follow the science closely, you'd understandably figure that's about all that lived in that shallow sea.

Our cast specimen restored in all its 3d glory

Truth be told, there were probably a few hundred types of fish in that seaway. Dr. Kenshu Shimada made a decent attempt to catalog all of them a few years ago, but like all good science on the Niobrara, it was getting out of date almost as soon as it was published. It's really amazing that 120 years after collecting work began in Western Kansas, new critters are still being found. I'm not going to go into details on them (I'll save them for other blog posts) and instead focus on this fish that is criminally underrepresented in the literature and online.

RMDRC 11-018, a massive 9 foot Ichthyodectes

If it's Wikipedia entry were any indication of its importance, what does the text containing a whopping total of 89 words tell you? That's right, 89 whole words, some of which are even talking about other related fish. Lame.

Some of the teeth of RMDRC 11-018. Yikes

Ichthyodectes, a fish with moderately terrifying teeth and with a body length approaching 9 feet, it's not cheered on much. Sure it's pretty common in the Niobrara, but it's also basically a pocket Xiphactinus (see, using the Wikipedia trick of talking about it's cooler cousin to gin up some interest). An average scouting season for us will find 5 or so specimens identified through cranial material. Probably more, but postcranially all ichthyodectids of about the same size pretty much look identical.

RMDRC 14-027, excavated with a film crew, watch for it soon on TV!

Perhaps a big reason as to why Ichthyodectes gets so little love is that there are so few specimens on display in museums, even fewer ones that look, um, not silly. Perhaps we need more museums to decide that decent specimens of lesser known fossil fish of the Niobrara are just as important for display as mosasaurs or sharks or Xiphactinus. Maybe I'm just asking for too much. In any case, I've pretty much doubled the amount of useful Ichthyodectes pics on the interwebs, so I'll count it as a win.

Lois gets prepped! Mostly!

It is unusual for us to move so quickly from collection to preparation and mounting, but sometimes the stars align. We're currently working on mounting the largest skeleton of Xiphactinus audax ever found, RMDRC 08-004 "Mildred". Unfortunately, the sharks got ahold of the carcass before it sank to the seafloor. They eviscerated it, and it is now missing most of its secondary fins, as well as chunks of ribs and spines. For a display specimen, this isn't really ideal, so we're using a few donor fish (ones that are way too incomplete for display on their own) for parts. These will be incorporated to complete the skeleton of the mounted fish, and their parts will be documented so not to make anyone think the composite skeleton is just a single animal.

Initial site view at TPI takeover

Jackhammers are a backsaver

Lois (RMDRC 11-021) was discovered early in 2011 by another fossil hunter that had mistakenly been scouting on property that was under contract with TPI. No big deal though, our crews came out to the site shortly afterwards and recovered the specimen.

Later in the day, big big hole

It was largely disarticulated and found with its caudal fin rays all around the skull region: the proverbial "head up it's butt" position that we frequently find fossil animals. The low rise over the fish was removed with a Bobcat and we set about finding the perimeter, or extent of the specimen.

Mike with chainsaw, Jacob for scale (2 meters)

Unfortunately the jackstrawed nature of the bones meant we'd have to remove the main part in a substantial field jacket. I don't like doing that, big jackets are heavy.

Cleaning the undercut for jacketing

Lois has somewhat flakier bone than usual for a fish, mainly because much of it was near the erosional edge, making preparation a bit slow and less than easy. The smaller jacket is nearly finished, as well as the individual parts we were able to remove on site. The large jacket may take a few more days to show prep, due to the bone condition. It will however be very useful in completing the original bone mount of Mildred, which will be started in the next week.

Just a photo of learning marker units in the field

Collecting a Xiphactinus: Kansas trip 2

Last week we went on a short trip to our Niobrara sites to collect a large specimen of Xiphactinus that was located by a 4H club member. Unfortunately the member had her boundaries confused, and found it on private property that she did not have permission to scout or collect on. Luckily though, we did. We still decided to nickname this fish "Lois" after the lady that discovered it.

Mike and Jacob in the hole, early in the morning

There was a lot of overburden to remove (volume-wise) because though the specimen wasn't deeply buried, it was spread 3 feet deep into the outcrop, along an exposure 9 feet long. A stirred up 15-17 foot fish is going to require a big hole, there's just no two ways about it. Hand tool digging was difficult, and we quickly escalated the equipment, first to an electric jackhammer (BTW I firmly believe everyone needs one of these things, they're awesome) and later to a bobcat excavator to knock down the bulk if the overburden.

The hole from another angle. Notice back-saving jackhammer!

We did this while it was still cool. Keep in mind this was one of the hottest days of the year. We awoke at 4:30 to get an early start. Funny thing: it doesn't get light this time of year in Gove County till 6:00 or so. Oops. No worries, we were pretty sure we could still get it out in one long day of work.

After bobcat work, expanding the hole to find the perimeter of the specimen

The fish itself was stirred up pretty severely, with the caudal fin exploded, spines everywhere, and the skull and pectoral girdle spread across the length of the excavation. On the bright side, this pile of bones will be a great basis for the restoration of the entire skeleton in a nice panel mount.

Dirty chainsaw work, with Jacob for scale

The stable pieces were removed and 2 jackets were carved out of the chalk with a chainsaw. 8:00 pm and we had it done. Only hit 95 degrees too. Much better than the 108 for a high the next day. I'm still exhausted from the experience.

Cleaning the undercuts in preparation for jacketing

Niobrara Trip #1 complete

Sorry it's been so long since the last blog post. Strange combination of field work and Chrome barfing the interface with Blogger on my end. Got it fixed now though. Hopefully.

Dumpy doesn't know if the sign is for the road or her

We went out last week on our first collection trip in the Niobrara Chalk of western Kansas last week, and had some great success. We went out with a class from the University of Tennessee Martin, and the students were a great help in covering outcrops that we hadn't looked at for a few years. The first recoverable item was found before the students had even arrived: a partial large Saurodon leanus skull, RMDRC 11-020. It was collected on a small knob really close to the surface with a plant on top. Roots did a number on it, but it is restorable as a plaque mount.

How many people does it take to jacket a mosasaur?

The second day of scouting with the whole compliment of people resulted in one of the students discovering a mosasaur skull, neck and partial torso coming out snout first of an outcrop low in the chalk (around MU 5), RMDRC 11-001. It looks to be a specimen of Platecarpus planifrons, with what appeared in the field as possible intraspecific bite marks across the snout. Ouch.

Standard TPI field pose

The next day we shifted over a section to the east and hit some outcrops that I had never scouted. The student that found the mosasaur managed to find a decent nearly complete Cimolichthys nepaholica, RMDRC 11-004, and not 30 yards away, an extremely large (9 foot long) Ichthyodectes ctenodon, RMDRC 11-018. Both animals were recovered. The Cimolichthys will be used in our 3D restoration project (which is ongoing) and the Ichthyodectes will be used to enhance our current 3D cast.

Perimitering the Cimolichthys before jacketing

The best part about it was that I was able to collect a few specimens for my pet research projects, including some Spinaptychus jaws, RMDRC 11-005-007 and a partial Martinichthys brevis skull, RMDRC 11-003. These rare little fish only appear to occur between MU 4 and MU 6 in the chalk, and material is pretty scarce, including skulls. Hooray for more data points!

Martinichthys snout!