Duckbill tails from the past!

We've been able to do a slight bit of preparation on a Maiasaura that was collected by TPI crews in 2004 from the upper Judith River Fm of Montana. Unfortunately no skin was discovered preserved in this jacket, however there were a few surprises.

The anterior 6 vertebrae show pathological neural spines, perhaps an old bite wound that healed. The chevrons (Y-shaped bones under the tail) are tiny, much smaller than what would normally be expected on a dukbill of this size.

This jacket contains 32 articulated caudal vertebrae in a string nearly 8 feet long. Strangely the chevrons are all nearly gone and the ossified ligaments normally found in ornithischian dinosaurs are completely missing.

And now for a rare one: Martinichthys

Even though the past two (hot) expeditions to Kansas have been primarily aimed at recovering various Xiphactinus skeletons that we have discovered over the years, we did have a little time to scout some outcrops low in the Niobrara chalk. Last Monday, I stumbled across some fish skull parts on an outcrop and followed them up to their source. This is what was coming out:

The rostrum of this rare fish is the most commonly discovered part recovered, mostly because it is the densest and most durable bit, and most likely to be found after weathering out of the outcrop. The teeth are tiny and resemble small barbs, though they number in the thousands. We may have found postcranial material with this fish as well, and a recovery operation at the site will be attempted next time we go to Kansas, though that may be a few months.

Martinichtys seems to have gone extinct between Marker units 5 and 6 (this specimen is the highest one I can find data for, about 1m below MU 6), as do several other animals int he Niobrara (such as Thryptodus, Tylosaurus kansasensis, and several invertebrates). I am curious what happened to wipe these species out.

Meet Tony II!

Well, field season started off with a bang this year. The little mosasaur snout I found in late April turned out to be a nearly complete specimen of Clidastes c.f. moorevillensis, which isn't really supposed to be in the chalk. The critter measures 4.8m long (16 feet), and is so well preserved that it retains cartilage in the ear, sternum, sternal ribs and above the scapulas.
Above, Mike Triebold uses a chainsaw with a special blade to separate the block away from the outcrop prior to jacketing. This chalk was the hardest we've ever encounterred in nearly 3 decades of collecting in the Niobrara.

The site as seen from the top of an adjacent bluff. Luckily we could drive up to the site to dropp off air compressors and generators!

Below is the prepared front half of the animal. 45cm (18 inches) of backbone was lost in the mid dorsal section due to erosion years ago. The tail section was taken out in another large jacket. Come see the specimen, now on display in our marine hall at the RMDRC!

RMDRC gets published!

A small project that I've been involved in for a few years, the discovery of the first heteromorph (open coiled) ammonite from the Niobrara Chalk.

Citation:

Everhart, M.J. and Maltese, A. 2010. First report of a heteromorph ammonite, cf. Glyptoxoceras, from the Smoky Hill Chalk (Santonian) of western Kansas, and a brief review of Niobrara cephalopods. Kansas Academy of Science, Transactions 113:(1-2):64-70.

We discovered the specimen while excavating the "Tracie" Tylosaurus nepaeolicus specimen in June 2008. Triebold Paleontology Inc. donated the ammonite to the Sternberg Museum at Fort Hays State University in 2009 after it became clear this was a scientifically important critter.

Email me if you need a PDF copy of the paper.

Kansas Field Season Commences

Well we're heading out again for a quickie recon before my trip to Korea. Hopefully it will be more productive then the last trip, which was a lot of uphill and downhill walking and very little in return. We recovered a partial Xiphactinus skull that I found accidentally last spring, and I found another skull and partial skeleton (so far, it's still going into the outcrop) that we'll be puling out later this spring. Above the first Xiphactinus, I also found and recovered a small turtle, probably Ctenochelys, that even had limb material. This next trip will not have a film crew, so things should go pretty quick!

Disassembling a large jacket

As many of you know, we had to remove our big Daspletosaurus, Pete 3, in 75 different jackets. Jacket RMDRC 06-005-72 was done with a pallet method, weighing in at 4 tons. Paper here on the process.

This week we are making a concerted effort to take that enormous jacket apart, in hopes of keeping it stable as well as recovering a large section of real estate smack dab in the center of the lab. Unfortunately, some bones are going to have to be broken or cut to "unjackstraw" them, but will be reassembled later. The jackstrawed nature of the bones (as well as their fragility) is what made us remove the huge block in the first place, so it's not like it's a huge surprise. Still, it is a lot of work.

BCT is finished!

BCT, our large Daspletosaurus that was excavated from 2001 to 2003 from a very very very hard sandstone in eastern Montana is now finished with prep. Paleo teach Jacob Jett finished the last dorsal vertebra, that was encased in a big ugly block of ironstone concretion. I'm just happy I didn't have to work on that!

Next up is restoration and molding. Stay tuned!