Monday, February 8, 2016

Viva la Muppetfish! 2 new species of Rhinconichthys unleashed.



Bob Nicholls's excellent reconstruction of Rhinconichthys purgatoirensis
So, we've been working on a little public/private partnership project for the past 2 1/2 years here at the RMDRC. In 2013 while he was helping advise on our Megacephalosaurus eulerti skull restoration, Dr. Bruce Schumacher, a paleontologist from the US Forest Service, approached me with a fossil specimen he had collected from the Comanche National Grassland in Southeastern Colorado. From what he showed me, I could tell it was a pachycormid, and one of those toothless specimens I am so fond of preparing. I had never been so giddy about a fish head in a concretion before!

Kevin Lindahl as he discovered the specimen
The super informative pectoral fin, our first clue to its identity
Bruce had already done some basic prep work on the top of the fish. Some paperwork with my boss Mike Triebold was completed and we were under contract to finish preparing, molding and casting the specimen. I spent several hundred hours with air scribes and air abrasive blasters removing the extremely tenacious concretion surrounding the skull. What we found on the underside was astonishing.
Top of specimen showing nice skull roof
The underside showing googly eyes and super long lower jaw
The fish has a remarkably flappy underbite with relatively huge eyes. It reminded us of the character Beaker from "The Muppet Show," and the informal nickname "Muppetfish" stuck. Of course that name isn't going to fly in publication, so we named it as a new species, Rhinconichthys purgatoirensis, after the local landmark river. A second species, Rhinconichthys uyenoi from Japan, is also described and Rhinconichthys taylori from England is better described with new information from the Muppetfish Rosetta stone. When we released the 2010 paper on Bonnerichthys, these species were touched on briefly, but only R. taylori was complete enough to work on.

Why is this cool? Well, we've gone from one species in the genus from one place to having representatives from all across the Northern Hemisphere for several millions of years. It also shows that commercial paleo and federal agencies can work together to get stuff done, to the chagrin of some in the academic community. The specimen is to be permanently housed at the Denver Museum of Nature and Science.

You can find a copy of the paper here: http://www.sciencedirect.com/science/article/pii/S0195667115301427



Sunday, January 10, 2016

Everyone loves a little tail

Or even a huge one. Just wanted to share some cool pics we took of Pete III's 5.1m long (17 foot) tail. Caudal 1 is missing from this layout (it was still in the pelvis jacket), so add on another 18cm or so.

Not too shabby

Jacob, our living 2m scalebar

The Fossil Brewing Company shirt is apt

Thursday, November 12, 2015

A day in the life of a Daspletosaurus bone

Some people asked me not too long ago about what we do in order to get some of these bones ready for molding. In the case of Pete III, our Daspletosaurus from Montana, the condition of the bone gave us some additional problems. All specimens of course get excavated and painstakingly prepared by our expert staff, but in Pete III's case, even the prep necessitated the invention of new techniques which I published on a few years back. The entire specimen was pixelated, with some bones made up of hundreds of thousands of fragments. Lots of glue was needed to even expose the bone, which is huge, literally Tyrannosaurus rex sized. Once done the left ilium looked kind of like this:


Next up is reconstruction of any major missing bits and holes with epoxy putty like Aves Apoxie Sculpt. That's the grey stuff.


We then apply a barrier layer of B-72 to hold everything together for the next steps. Shiny!


Then we take our gorgeous bone and smear the whole thing with tinted Hydrocal.


 Yuck. OK now it doesn't even look like a fossil. Never fear, most of it will be gone soon. The main aim is to work the Hydrocal into all the seriously tiny cracks in the surface to better hold the bone together. This also reduces the amount of the relief in the specimen so molding goes much faster. The excess on the surface is removed with air abrasion.


Doesn't look so shiny anymore, but we can fix that with a wee bit more of very thin B-72.


And there you have it, one half of a bone restored in a few days time. Now we just make a support jacket so the entire thing can be flipped over and the process repeated.




Wednesday, September 16, 2015

Please welcome the new "Avaceratops"

It's a happy day when we get to unleash a brand new dinosaur on the world. After 3 years of hard work and a lot of sweat, we get to show off our new primitive centrosaurine ceratopsian!
The newest skeletal, copyright Scott Hartman, used with permission

The skelton in all it's glory, Curator for scale
The bones of the specimen that were recovered, copyright Scott Hartman, used with permission

We discovered the specimen at the end of August 2012 on private land in central Montana. The specimen was found near the top of the Judith River Formation, in rocks approximately 75 million years old. You may notice we are using the name "Avaceratops" in quotes here. We're not trying to be coy or mysterious, but with the stratigraphic difference (our specimen is about 3 million years younger than the holotype) and the differences in skull morphology highlighted below, we have come to the conclusion that this is a different animal than true Avaceratops lammersi.

Someone put a lot of work into this. Tell me who you are so I can give credit!
The skull is quite different in detail. It totally lacks a nose horn, and the long brow horns (until recently a rarity in centrosaurine ceratopsians) point forward and even slightly back towards each other, much different than the other two known skulls. It's large "forehead" area is more reminiscent of the recently described Nasutoceratops, from about the same time in Utah.

Overall, the skeleton is 3.5m long and about 1.2m tall. We estimate the critter was about 3 to 4 years old when it died, both based on its relatively small size and the extensive lack of fusion in its skeletal elements. It's pelvis was reassembled from over 30 separate elements. What a job.
Digging down into the quarry site

After the dinosaur died, it's partially mummified body washed down a stream channel until it hit a logjam composed of not only actual logs, but the limb bones of a large hadrosaur. Here it lodged upside down and then began to partially disarticulate. Some of the dried skin over the hips was surprisingly well preserved though, as addressed in an earlier blog post. A few tyrannosaur teeth were found at the site, but we feel those were incidental background fossils, as no predation or scavenging marks were observed on the bones.

Tyrannosaur tooth found at the site

After all this painstaking work in sometimes miserable conditions, we are excited to share the product of this discovery with the rest of the world. After getting unveiled to the press on Wednesday, September 16 at 10:00am the mounted skeleton will be on display at the RMDRC for just a few weeks before making its first trip to Dallas, TX for the 75th meeting of the Society of Vertebrate Paleontology. You must come see it!
The mount showing the horn shapes (and absences)

Rear view of skeleton

Wednesday, August 26, 2015

Digging the middle half of a Triceratops

We've finished the Triceratops dig that I announced in my last blog post. We got pretty much everything from the rear of the neck to the back of the hips, minus the limbs. It looks like the specimen was well laid out in order, unfortunately with the head end going off the edge of the cliff. Just a couple thousand years too late, but oh well. There was an unconformity at the top of the site that destroyed the higher bones, including shearing the bottom 4/5 of the femur away. Sometimes nature isn't nice to us. Enjoy the pics!

Scary bobcat driving to get rid of overburden

Mike not finding anything, Jacob on the hips

Naptime in the shade while employees roast

Hips isolated

Cap jacket on hips and attempting to recover a whole rib

Big jacket done after a seriously long day


Prep on the main hips block is going slowly, but we hope to have this monster chunk of bone out on display later this week.

Progress on the jacket but still lots to go

Wednesday, July 29, 2015

Hell Creek: What I found on my summer "vacation"

We've just returned to the lab from a 2 week expedition to the Hell Creek Formation in South Dakota. The weather was very hot, the bugs were out in force, and I had a grand total of one shower during our stint in the wilds. Here's a bit of what we found.
Thescelosaurus claw
Theropod tibia

partial triceratops skull before excavation


Finds were a bit sparse in week one. Lots of hiking and lots of incredibly bare outcrops. Occasionally I founds some Champsosaurus bones or gar scales, but for the most part it was just a bit depressing. Then I made my big "find" of the first half of the trip: a Pachycephalosaurus dome!
Not a pretty dome

but they're so rare

Just when things were starting to look bleak, I found 2 Triceratops sites a few days apart. The first so far is just a pile of ribs (we will expand the dig later to see if more is present) but was in a great location where we could drive the truck to, no overburden, really ideal.
We can always use more parts

The second one, in true Anthony fashion, I found by tracing a bone fragment to the top of a 50-60 foot cliff that had bones sticking out of it. I knocked out a very small excavation the first day and kept running into more bones. Jacob and I returned for a few more very hot (120 degree plus) excavation days and found over 20 bones so far. A few were recovered, and we will return to the site in a few weeks with a bobcat to move some serious dirt and continue the excavation. So far it's mostly really big vertebrae, ribs, and girdle elements, though there is some skull and rooted teeth too. Fingers crossed for a complete-ish specimen!
Looking down from the site. Part of the humerus can be seen poking out

Looks like quite a climb up to the site

Dorsal vertebra awaiting excavation


Monday, June 22, 2015

Digging more holes in Kansas

It's been quite a while since the last update, but that's because of all the field work we've been doing in western Kansas. Hell, I feel like I've been digging deeper holes than Kansas' Governor. Ha! Biting political humor.

In any case, Jacob just released a video that has a few awesome action shots of me staring at the ground, and a really ugly (well, even uglier than usual) Xiphactinus that I found before we started working on it. Check it out and don't forget to subscribe to his youtube channel or the Dinosaur Nerds website so you can see all kinds of boring thing like me complaining about mosasaurs.