The Reassembly of Dillon III- Finished

After a final binge of puttywork and painting of the restored/donor plastic pieces, our Platecarpus sp. RMDRC 10-007 "Dillon" is ready for its public debut. Be sure to check it out this week in Denver at the Coliseum Gem and Mineral Show.

The Reassembly of Dillon II- Mosasaur Boogaloo

The Mosa-tissarie is alive and well. Back from the field (more on that in another post) and right into the final push of this project! The lower jaws are now mounted although still a bit wonky. Just about everything is in place and now it is time for the final restoration of the teeth, braincase and pterygoids. The last step will be painting all the restoration to match the original fossil color. Be sure to come visit it at the RMDRC before it heads off to the Denver Coliseum show next week.

The Reassembly of Dillon

The squished incomplete and partially disarticulated Platecarpus sp. skull is coming back together! It's taking a lot of time and some hefty restoration, however it does indeed now look like something!

The top of the skull has a welded steel support frame holding everything together. Lower jaws will be removable for shipping but also are attached to a steel superstructure. All missing parts are based off of our Platecarpus planifrons cast, including the donor braincase (which is an odd thing to go missing on a skull and neck this complete). Next up is mounting the 5 cervical vertebrae recovered with the specimen and final detail/paint work. Hopefully it will all be finished shortly after Labor day!

Basilemys reconstruction

In 2007, a friend of Dr. Kraig Derstler accompanied TPI crews doing field recon in the Judith River Formation of central Montana. In one gully he discovered some very large turtle shell parts coming out, and we traced them to their source. Though obviously belonging to the "emperor turtle" Basilemys, this turtle looks as if it had swallowed a hand grenade, where all parts were disarticulated and spread through the outcrop.

Excavation was conducted in 2007 and 2008 (and even a bit in 2009), and about 50% of the animal was recovered. Since the specimen, now nicknamed "Doug" after the discoverer, is disarticulated, this gives us a great opportunity to reconstruct the specimen in inflated form, as opposed to the crushed articulated specimens found until now.

This specimen is also remarkable because it preserves several non-shell skeletal elements, which is rare for this type. These include both pelvis assemblies, scapula, dorsal vertebra #1 and toes. An isolated Basilemys humerus found on a nearby ranch will also be used in the reconstruction. Stop on by the museum to see how the project is coming over the next few months!

More Cephalopod Fun

Throwing a bone to the invertebrate guys out there, here's new images of RMDRC 10-018 Spinaptychus sp. that yours truly found earlier this spring in Gove Co., Kansas. Ammonite remains are fairly rare in the chalk since the aragonitic shells do not readily preserve. These jaw parts however are calcitic in nature, and are occasionally found. We lent this specimen to Neal Larson of Black Hills Institute for detailed preparation and a bit of restoration before molding. He and his staff did an absolutely phenomenal job. Thanks again, neal!

The specimen is fairly large at over 5 inches wide, 4 inches long. The next project is determining what ammonite this specimen belongs to. Hopefully a paper will be coming out soon!

The Disassembly of Dillon

Back in April of this year Paleotech Jacob Jett discovered a small mosasaur in the upper Niobrara Chalk of Logan County, Kansas. This critter, a Platecarpus (RMDRC 10-007) consisted of a skull and 5 cervical vertebrae. Part of the upper jaws were exposed at the surface, and there was extensive calciteAbove, Jacob works on preliminary excavation immediately after locating the specimen. Luckily there was little present in the way of overburden.
A few hours later, Jacob has found the perimeter of the specimen (he finally discovered something, so I went to search other areas of the outcrop, finding the big Clidastes Tony II RMDRC 10-008). The entire exposed area will be covered with a plaster and burlap jacket to transport back to the lab. Unfortunately, after the jacket was made, the area was hit with torrential rains (6 inches in 24 hours) and we were not able to get back to the jacket to bring it home. It had to sit out exposed to the elements for 2 weeks.
The jacket was "show prepped" (prepared to expose what is present) once it returned to the lab. As you can see, most of the skull is there, missing only parts of the left maxilla and for some strange reason, the braincase! I am currently in the process of getting these heavily concreted bones separated so that Dillon can be reassembled as a 3d skull and neck mount. As you can guess, it is a time-consuming and delicate process, and the results will be shown in the next blog update.

More on Gil

Show prep is continuing on our duckbill! Time for a little background information. Gil, AKA RMDRC 04-001, was discovered in 2004 by and is named in memory of "JC" John Cully Gilpatric, who sadly passed away 2 years ago. It comes from the upper Judith River Formation, putting its age somewhere around 75 million years old. Excavation began on June 26, 2004 and had been completed by July 2nd. Gil wad found in a fairly soft sandstone with low overburden, which greatly sped up the recovery.

Above is a sketch of the site when TPI field crews excavated it that summer. As you can see it is highly articulated but missing the skull and lower legs. Unfortunately for hadrosaurine hadrosaurs those also happen to be the most distinctive parts, so identification down to genus is still a little tentative. We have been considering Gil to beling to Miasaura, however there exists the possibility that It could belong to two other non-crested duckbills that existed at the same time: Gryposaurus or Prosaurolophus. Below is a photo of the 54cm long right humerus, which may or may not be distinctive. In any case it's pretty, and also slightly longer than the radius.Prep work is ongoing to find more distinctive skeletal elements, so that we may get a better idea of the true identity of this critter. Special thanks goes out to Dr. James Kirkland for providing PDF reprints so that I may attempt to clear this up!