More odds and ends

At the moment I'm preparing the grand annual update to The Compact Thescelosaurus. If you've been following along over the past couple of years, it doesn't take being Sherlock Holmes to guess what it will be. Actually, it doesn't even take being 1940s Radio Program Watson to guess, but do act surprised. In completely unrelated news, there's a taxon published this week I recommend you see: the little croc Thikarisuchus xenodentes. (What, you were expecting the theropod?) T. xenodentes, from the Cenomanian-age Blackleaf Formation of Montana, had a sharply triangular skull in top view and strongly differentiated teeth, among them the expected bitey teeth at the very front and long, low, narrow teeth at the back. This small croc may have had a taste for plants, or perhaps sliced up insects.

Something we love around here at Equatorial Minnesota is historical content about Minnesota geology. You may be familiar with the Minnesota Geological Survey's publication archive. It turns out that there are a bunch of MGS field notebooks scanned and available via the University of Minnesota libraries. You can find notebooks there from paleontologists such as Frederick Sardeson, Robert Sloan, and Clinton R. Stauffer, all of whom curiously have last names starting with "S". (Also interesting: Sardeson's field notebooks all have the left-hand pages filled out, but right-hand pages are much less frequently used. Was Sardeson a lefty?) There are also materials from the Department of Earth and Environmental Science.

Do you prefer to see your geology in the field? I came across a nice section of the St. Peter through Platteville under the I-94 bridge, on the east bank of the Mississippi. I'd been there years before but don't remember being so impressed with it. Maybe it wasn't as well-exposed then, or maybe I just wasn't experienced enough to appreciate it. The Platteville interval at the top was definitely exposed, but maybe this lower exposure is the result of more recent erosion or something. It definitely bears further photography and investigation, as it has a great view of the Glenwood.

The important part looks like this.

And here's what it looks like if I annotate all over it. I'm not entirely confident with the thickness of the Hidden Falls Member; for some reason the Mifflin is really grungy here. The Glenwood bits are open to interpretation (the Nokomis gets "Glenwood/St. Peter" because it's technically in the Glenwood but can't be distinguished from the St. Peter in well logs or gamma logs). The Tonti Member makes up most of the St. Peter Sandstone, if you're curious. There may be some Carimona at the very top. 

Oh yeah, also saw Bridal Veil Falls nearby, which has, y'know, seen better days, but is still running, after a fashion.

Or maybe you'd like some historical trivia? One of the things I wanted to find more about for the Mammoth Cave National Park paleo inventory was whatever became of the type specimen of Lithodrumus veryi, a Mississippian coral possibly collected from the park. It was described in 1904 by George Greene and the specimen has been lost to science since at least 1944. Greene's collection went first to the American Museum of Natural History and then to the National Museum of Natural History, but Lithodrumus veryi apparently went missing, as Easton (1944) couldn't find it at the AMNH. Just a few days ago I was looking up images of tabulate corals when I came upon a post at Louisville Fossils and Beyond that stated one cabinet had not been sold, and its contents were eventually going to the Indiana State Museum. Hope springs eternal! I've sent a message to the Indiana State Museum to see if perhaps L. veryi's type is there.

It's supposed to look like this (Greene 1904: Plate 49). Have you seen it, by any chance?

So that's what's going on around here. (Oh, that and some unusually intense bot "readership", or the whole of Hong Kong has suddenly discovered a passionate interest in the Ordovician fossils of Minnesota and Elliot Formation prosauropods. Maybe I'm cynical.) Tune in for the next post!

References

Allen, H. J., E. W. Wilberg, A. H. Turner, and D. J. Varricchio. 2025. A new, diminutive, heterodont neosuchian from the Vaughn Member of the Blackleaf Formation (Cenomanian), southwest Montana, and implications for the paleoecology of heterodont neosuchians. Journal of Vertebrate Paleontology e2542185. doi: https://doi.org/10.1080/02724634.2025.2542185

Easton, W. M. 1944. Revision of Campophyllum in North America. Journal of Paleontology 18(2): 119–132.

Greene, G. K. 1904. Contribution to Indiana palæontology 1(17): 168–175.