Introducing "Bev"

We have a new addition to the RMDRC mosasaur family: a Platecarpus ictericus from the upper Niobrara Chalk of Logan County, KS. I discovered this one on June 17th, but we didn't return to excavate till the 19th.

It appears to be a complete skull and cervical series, with a number of articulated dorsal vertebrae and ribs. The skull is scattered, but preserves not only all of the bones, but also calcified cartilage. This specimen is a great candidate for further preparation and 3d

mounting. Judging by the size of the lower jaws (18 inches) the complete animal would probably be 18 feet long. Unfortunately, scavenging sharks (probably Squalicorax kaupi, however a Cretoxyrhina mantelli tooth was also found on the same outcrop, rare in the upper chalk) forcibly removed the front limbs from Bev before she hit the bottom of the Western Interior Seaway 83 million years ago.

You may notice that we give nicknames to the specimens, and there is a great reason why. This mosasaur was discovered about 30 feet away from (and 15 minutes after) another Platecarpus specimen on the same outcrop. Instead of referring to them a "you know, the first mosasaur that Jacob found that week", we name them to keep them straight, both in the field and the lab.

The person that discovers the specimen gets the naming rights. In this case Bev is named after my mother. It's a great way of discovering which relatives like you best.

Fun in the chalk

It was a good trip...

We only got 2 days of scouting in before getting rained out of the field on Saturday, however we found some good new specimens. Jacob Jett was able to find his first mosasaur, a >Platecarpus specimen in the upper chalk of Logan County. I stumbled upon another mosasaur, >Platecarpus ictericus, about 30 feet further down the same gully, and elsewhere on the same private ranch I discovered the hips of a large diving bird, >Hesperornis.

Thursday we spent the day excavating a giant fish with Mike Everhart, currently identified as Protosphyraena gladius, however that seems likely to change in the next few years. It was extremely hot and humid, with the temperature at 7:00pm at 103 degrees. The photograph shows Mike Everhart, Jacob Jett and a little bit of Mike Triebold at the excavation site.

Friday and Saturday were spent excavating the >Platecarpus specimens, and all the fossils made it safely back to our lab. Be sure to stop by in the next month to watch us prepare these critters and more in our lab viewing area.

Off to the field!

No fossil of the week this time, our field crew will be headed off to the Niobrara Chalk in western Kansas bright and early Wednesday morning to investigate and recover more sea critters. I'll be taking lots of photographs so you can all see who's there and what we do, even some of the stuff we don't tell you about on our tours of the RMDRC.

Currently in the ground we have a small shark (probably Squalicorax falcatus), a small (12 foot) Xiphactinus audax, and a gigantic (18 foot plus) Xiphactinus that was partially poached from the rancher's property. Also, we'll be investigating a giant clam, Platyceramus, in hopes of putting it on display in our marine hall this summer. And who knows just what we may stumble upon once we start scouting!

Fossil of the week: 6/9/09

Let's talk big fish this week!

Ichthyodectid fish are amongst the most common fish found in the Niobrara chalk. The genera Prosaurodon, Saurodon, Saurocephalus, Gillicus, Ichthyodectes and the giant Xiphactinus are all found at various stratigraphic levels. Fish have very delicate skulls, however many times they are recovered articulated. It is impossible to disassemble these skulls without damaging them, so we usually prepare them in profile view. Sometimes they are disarticluated, looking like they reenacted the final scene from "Jaws 3D". These scattered skulls enable us to reassemble the pieces and take out some of the crushing distortion from 82-86 million years of burial.

The photo is of a specimen of Saurodon leanus named "Tony" that I discovered in Logan County, Kansas in October of 2006. Stratigraphically we're at about marker unit 18, so fairly high in the chalk, nearing the Pierre Shale contact. This is one of the more rare fish in the chalk, caricterized by it's long eel-like body and distinctive chin spike. As you can see, the bones of the skull have blown all apart, making this specimen a great candidate for molding and 3d reconstruction. No one is quite sure what the spike is used for, my guess is probing into the bottom muds of the western interior seaway looking for soft bodied invertebrates (such as worms) to eat. Hopefully we'll find more specimens in the future that may include stomach contents.

Fossil of the week: 5/29/09

This past week I was attending the 8th Conference on Fossil Resources in St. George, UT. The second group of talks all focused on the Campanian aged flora and fauna of the western interior. A few brief mentions of the poor neglected duckbill dinosaur fauna were made, but I wanted to share with you an image of one that I'd love to find: "The duckbill that ate Manhattan!" Paleo Tech Jacob Jett (6'4" tall, shown back in his younger days) is shown for scale.

This isolated rib bone was discovered in the upper Judith River Formation (Campanian aged) in the summer of 2004 while excavating a centrosaurine horned dinosaur called "UTC". Isolated duckbill skeletal remains are not uncommon at dig sites. In fact, juvenile hadrosaur jaws have been found at both our  "Joyce" and "Pete 3" sites in the same area.

Unfortunately, isolated postcranial remains on hadrosaurs aren't very diagnostic, so it is impossible to say which critter this rib belongs to. It is a good deal longer than our longest rib on "Big Ed", the 34 foot long Edmontosaurus annectens that is now on display in Korea. I'd estimate the body length of this duckbill to be at least 40 feet.

Fossil of the week 5/14/09

In honor of this week's late update, I present to you "Holly" RMDRC 09-007, a pterosaur from the lower Niobrara Chalk of western Kansas. It's only fitting, since the excavation of this specimen is the reason this week's update was so late. confirmation of the genus waits on further prep work, though we have a pretty good idea what it is.

I discovered this specimen Monday morning while scouting on a private ranch. Excavation took about a day, and the entire specimen (including the rarely preserved skull) is back in our lab now. The blocks contain most of the body and wings as well as the rear portion of the lower jaws. Preparation will commence as soon as I get back from a small spurt of paleo conferences over the next few weeks.

Pterosaur remains are not uncommon  in the Niobrara, even though our dig sites are several hundred miles away from the nearest shore. Pterosaurs were strong flyers, and appeared to spend quite a lot of time hunting over the open ocean. The males had elaborate crests, most likely to attract females, just like their very distant cousins today!

Fossil of the Week 5/2/09

For this week's dinosaur, we venture up to Montana and the Judith River Formation, 75 million years ago in the late Cretaceous. Larry, a rancher who loves to hunt for dinosaurs near his home, was exploring badlands with Dr. Kraig Derstler during the summer of 2007. He had just finished wagering Kraig the princely sum of 2 quarters that he could find a diggable dinosaur fossil first when he came across hadrosaur bone fragments weathering out of a very steep slope. A bit of excavation revealed a few bones clustered together, luckily a RMDRC field crew was already en route to Montana, and we would spend the next month at the site.

In the photo, Dr. Kraig Derstler and Paleo Tech Jacob Jett work on breaking up a large sandstone block above the dinosaur (under the white cloth near their feet). Small man-portable jackhammers help tremendously with digs like this.

Most of Joyce (Named after Larry's wife, whoever finds the dinosaur gets to name it) was buried fairly quickly, with only a few shed tyrannosaur teeth in the quarry indicating limited scavenging activity. Unfortunately, not long after Joyce was buried, a small creek had cut through the site removing most of the tail. Somehow knowing it had been missing for 75 million years made us feel a bit better. From the limbs, vertebrae and skull were were able to tell that it was a lambeosaurine duckbill dinosaur, one of the types with a head crest. The pile of bones was so extensive that we had to remove most of it in one large jacket, and slide it up nearly 50 feet of slope to load on a trailer. Preparation is ongoing, and we hope to have some bones on display in the coming months.

Joyce made her television debut in 2007 as well, with NBC Nightly News and ABC (Australia) both having camera crews visit us at the dig site.