Back again after another week of baking my brains out in the chalk in search of long dead marine critters. We were focusing on a strip of outcrops that exposed MU 4 to MU 6 in the lower Niobrara chalk. Found some good stuff too, a nice
Pteranodon sternbergi (which will be the focus of another post once prep starts), a partial
Xiphactinus audax skull, a small
Pachyrhizodus caninus tail, some
Martinichthys rostra, and a whole bag of
Martinichthys poop! If anyone has any research interest in this poop, let me know, I'd be happy to provide samples.
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| Pteranodon site |
The
Pteranodon took up most of our time on till Wednesday, but late that afternoon, Jacob and I finished up and moved on to some outcrops that our crews hadn't explored for a few years. Erosion in the chalk is surprisingly quick, so searching the same spots every 2-4 years is extremely productive. We drove the truck over next to an outcrop and decided to take a quick snack break. While chewing on a small bunch of Red Vines, I look over and notice something blue on the face of the outcrop. "what the hell is that?" I ask Jacob, thinking it is probably just a piece of garbage from the oil rigs in the field.
We go over and investigate, since we had to scout the outcrop anyway. Upon inspection we discover this:
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| Peek A Boo |
A pachychormid fin eroding out with a layer of blue plastic over it. The chalk above the layer was obviously disturbed, and there were small plants growing out of it. Someone tried to poach this fossil!
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| It's like christmas |
We reopened the hole and followed the fossil in. The blue plastic extended quite a ways in. To the end of the fin in fact! Someone excavated the entire thing, then left it! Amazing. We pulled back the plastic and to my surprise it revealed the longest
Protosphyraena perniciosa pectoral fin I'd ever seen, 2'8" (82cm) from tip to erosional edge. There were a few fragments in the float and a piece of a radial, but I'm fairly confident we recovered pretty much all of the specimen. Good thing too, we finished up just as another severe thunderstorm was bearing down on us. Also: DON'T STEAL FOSSILS!
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| Jacketed! |
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| The monster storm a few hours later |
Back in the lab our summer intern, Lisa, had the job of preparing the specimen . She did a beautiful job! Now to find an interesting way to display the specimen in the museum.
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| Big fishie |
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| With nasty pointy fins |
Nice job... I didn't get the impression that it was complete to the tip from your initial photo. It is interesting that the "teeth" are very large and distinct on this specimen... others that I have collected seem to vary in tooth size from fin to fin... may be sexual dimorphism ... or just intra-species variation... dunno...
ReplyDeleteIt's an awesome example of the teeth in this species of Protosphyraena. I think we have it all the way to the tip, but since we didn't do the initial excavation, I'm not 100% sure they didn't chunk a bit of it when they uncovered it.
ReplyDeleteErmmm, fin teeth I mean. Not tooth teeth. It's been a long morning already...
ReplyDelete