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

Ava Restoration Update: March

Reconstruction of the skull started with 40 individual bones

Whether they are big or small, all ceratopsians sure do have a lot of parts. When they are juveniles like our Avaceratops, the lack of fusion in bones makes that even more apparent. For example, the sacrum (the wad of bones that holds up the rear end of the animal) in adults is usually one giant unwieldy piece. In our young animal, it is 26 individual parts, all with some degree of crushing, though not always in the same direction or degree.

Sacral neural spines molded

More of the massive piles of sacral parts

We've finished preparing the specimen and are busy restoring the individual bones to get molded. Restoration is a catch-all phrase that can mean anything from putting a protective layer of consolidant over the surface to sculpting missing bits to molding crushed vertebral centra, casting them, then cutting up the casts to re-inflate them to their appropriate size.

Most of the ribs, many crushed in strange directions

We're even using our trusty 3d scanning and printing equipment again to make precise mirror images of elements we are missing from one side to help complete the skeleton. In the end we'll end up with everything we need for a full sized standing cast skeleton, hopefully by Memorial Day.

Dorsal neural spines. Each one gets a centrum once restored.

Keep watching the updates on this blog for more news and pics of the restoration, molding and mounting project.

Platecarpus restoration complete! All hail Cap'n Chuck!

After 8 long years of work, our Platecarpus tympaniticus specimen RMDRC 06-009 "Cap'n Chuck" is finally finished! These last few weeks of the project had been dedicated to finishing the details of the armature as well as packing it for its trip to its new museum forever home. It seems like just yesterday when I was lifted in a freezing drizzle in a Bobcat excavator bucket one October day to investigate a lonely vertebra poking out of the side of a gully wall. Poking around revealed what looked like the rear of a skull, and we decided to come back the following spring to finish the job.

Working on turning a vertical surface into a flat surface

By the time we completed the excavation, we could walk down the debris pile to the gully bottom. We took out multiple jackets since the bone density was so high, working on them in the lab was much safer for the specimen.

Main body and skull block in the Show Prep stage

Once "show prepped" (preparing the jackets to show what is inside of them) we disassembled them and placed the bones in drawers in the Clean Room for safe keeping. There it stayed for years until a customer was found.

Coming together. The white bleached bone 4th from the left is the first bone found

Earlier this year we started restoring the bones for mounting. While we had the bones handy, Cap'n Chuck was molded so copies can be sent to other museums in the future. The mosasaur was incredibly undistorted, the ribs were even round in cross section, unlike the typical Kansas condition of being squished pancake flat.

Dillon (left) vs. Cap'n Chuck (right)

Snakey!

The final result is pretty spectacular. The undistorted ribs helped us get a very accurately shaped torso, with cartilage and even an interclavicle. The skull is beefy and bulldog-like, much different than the lower chalk specimens of Plesioplatecarpus planifrons.

Showing off the pterygoid teeth

Paddle and chest detail

Vertebrae are much larger and more robust than the lower chalk specimens. Surprisingly, the finished mosasaur was a bit shorter in length than we had anticipated, coming in at just over 17 feet (5m) long.

Skull detail

Beefy Platecarpus Restoration Update!

For the past few weeks, TPI field crews have been scouring the outcrops of Western Kansas and finding some spectacular specimens. More on those in a future blog update.

Since the field crew was gone, the lab crew is much less distracted and has made great progress in assembling the Cap'n Chuck specimen of Platecarpus tympaniticus. Skull reconstruction is now complete and painting of the small restored areas is all that;s left. total length ended up being 52cm, but the width gives it more of a bulldog appearance than the lower chalk Plesioplatecarpus planifrons. I'm still trying to get used to all these new names since the reclassification of plioplatecarpines a few years back.

Top view

The only bones I was completely missing were both squamosals, but they were pretty simple to fabricate.

If you look carefully, we even included the mounted epipterygoids

The skeleton has had individual clips fabricated to hold each bone securely in place. Those subassemblies are now being fastened to the armature. The specimen is intended to be hung at its future museum home, however building it on cables in the lab is too unsteady. The posts supporting the superstructure will later be removed before shipment. The light colored vertebra fourth from the left is the first part of the mosasaur I discovered coming out of the outcrop.

Ribs beginning to be fit, though all still need adjustment

Individual bones are assembled into segments so that it can be quickly and precisely set up in a new facility. All limbs are removable, as are the ribs and skull. The vertebral column breaks down into segments. With any luck though, the steel armature will be nearly invisible on the final mount.

Front paddles nearly assembled.