Search the Community

Hi, I know this is pretty rough. I had been attributing it to Eldredgeops, but I find no mention of Eldredgeops in the Michigan or Ohio Dundee. However all the old writers mention Proetus crassimarginatus, which I think now is Crassiproetus. I don't know if there is enough here to distinguish, but the margin along the pygidium has bothered me all along for Eldredgeops. FYI there are only 5 trilobites mentioned in any of the literature for the Dundee down here. Pseudodechenella nodosa and planimarginata, Trypaulites, Coronura and Crassiproetus. Of course there are many Eldredgeops not many feet up, but none preserved anything like this. Thanks for any help you can give. 355471148_9576358892434785_6581400298562770854_n.mp4

Hi, I don't want to over post, but this is my only venue for this. Here first is a nice big Pseudodechenella planimarginata pygidium that I like because it clearly shows 15 axial segments on the pygidium. I thought I had counted 15 on smaller ones, but they get blurry. Is 15 diagnostic for thei species? Second is a nice Trypaulites calypso, which are quite uncommon (this is only the second decent one I have found). Third is interesting and I'm wondering if it might be a T calypso thorax. It was definitely in the same layer as the pygidium. I've not ever seen anything like it. I also don't know iff the shell manes sense as it is not in individual ribs, or it doesn't look it. It looks like there is more in the rock, but I'd be afraid to take my Dremel to it, I think. What do you think? Thorax?

Hi, I finally got to digging this butt out, which I wanted to do since it is so large. It is 2 cm long. But has anyone ever seen an axial lobe like this? It is over a CM high at the front. It is MUCH larger than any other I have found, Have you seen any like this? Is this perhaps a mature one, when all the others are not? Is it deformed? I mean the shell goes down the other side the same way, but I am having a terrible time exposing it. Not also how very thick the shell is. Interested in any input. I never know I could find bug butts so fascinating. I sure wonder what it looked like whole. Thanks

This was an oddity in my Dundee Formation material (Mid-Devonian) I decided to bring home out of curiousity. The material itself mostly contains white silicified fossils in sandy/packstone pulses with some grey crystalline chert horizons. The colouration of this piece, and its general shape, gave me pause as it seemed a bit out of place. Initially I thought, "possibly a fish bit?" (stout spinal process)? but the internal structure didn't strike me as likely. The specimen measures about 7 cm long. My second thought was possible plant material, but I am rubbish on plant identification in the Devonian. It could, of course, just be a geologic feature, too, but the very conspicuous shape makes me lean toward fossil.

I was able to get out three times to three different local spots. Fairly underwhelming results, but it was nice to get back out in the field now that the snows have melted. The first two spots I had effectively tapped out last year, but it always pays to check in. The third one, featured here, was a new prospect. I had made a cursory visit last autumn, and then tried to jump the gun by going here at the end of February but the snows were still too deep. Exploring the Dundee Formation is admittedly a pretty niche focus. There is probably a good reason why it isn't the top destination for fossil collectors on account of lack of available outcrops, some very poor facies, and occasionally being brutally hard rock -- so much so that it is commonly used as armour stone for landscaping. Friday's prospect had quite literally hundreds of tons of locally quarried rock. Sadly, about 99% of it was not very gainful for trilobites, and was from a lower facies that is characterized by being a high energy packstone filled with crinoidal bits, broken brachiopods, and shreds of fenestrate byrozoans.

The older I get, the more spring has an appreciable effect on my energy and outlook. But, it also signals an end to cabin fever and getting back into the hunt. Spread out over two non-consecutive days, I took to getting back into practice by doing some collecting nearby. There are no "wow" specimens here, but certainly typical ones I find from a wide mix of stratigraphic units all in one place. The first is one of the areas I focus on, which are mostly little gullies where some larger rocks are exposed, and smaller ones get sifted.

Another London oddity. While scoping along the Thames River among the usual Devonian-era debris, this caught my eye. At first I thought it was just a spirifer impression, but upon closer examination, it had a kind of border reminiscent of the pygidia I see on Pseudogygites. Obviously, it could not be Devonian if that were the case (the rock would have to travel pretty far some long while ago to be Ordovician in origin). Would this be another Basidechenella? If so, the pygidium is about 2 cm (~1"). Or my eyes are playing tricks on me, being rusty after the winter

Just ten minutes ago while walking along the river on campus, I came upon this rock with a tube-like piece. The rocks in this river are generally glacial till and more erosion-resistant limestone from the Devonian (Eifelian - Dundee Fm). The tube, about 1.5 inches long, is a bit too straight to be a worm burrow, lacks any of the segments of a crinoid, perhaps too thick to be the edge of a wide spirifer, and it appears next to a brach impression. I just want to be sure if it's geologic or not before I decide whether to keep it. I can try to put the microscope on it later to detect any closer details, and maybe see if I can remove some matrix. But perhaps someone here knows exactly what this is. EDIT: Texture is smooth and somewhat reminiscent to shell material. If it is a brach hinge, it may be sloping away from the edge of the rock as there is no trace of it on the edge. And, if a brach, an odd deposition!

Made a short and first of the season visit to one of my honey holes. It is mostly large piles of regional riprap (a majority of it Dundee Fm). Although there isn't much of this specimen left in terms of the impression, the cephalon below the pygidium is throwing me. In this particular type of rock, I do find Proetus pygidia, which is why I'm leaning toward that as an ID. That being said, the border around the cephalon is making me second guess if it is perhaps a Dechenella. If I recall correctly, both species have a fairly distinct genal spine (but Proetus having a more blunted one). scratch that... it just may be another plain old Elderedgeops rana

There is nothing quite like a good hike wending around the river through the Carolinian forest ecosystem as the black-eyed susans and goldenrod stand proudly as the mayapples wither, and enormous puffballs appear while chipmunks and squirrels scamper about to hide their finds before winter comes. My goal was to return to an area that looked promising, mostly composed of rounded deposits from when the river was much higher some 7-10,000 years ago. The limestones in this area vary in terms of composition and state of preservation, as well as the deposition of marine critters: some stones will crumble into chips that are filled with large clusters of very tiny brachiopods, while others will have small crinoid columnals, long worm burrows, rugose corals, large-ribbed spirifers (some with very long "wings"), and even the occasional trilobite pygidium. Today's trip did involve getting a bit dirty and sifting through moss, frightening at least one salamander, a few garden snakes, springtails, woodlice, and an arachnophobe's nightmare's worth of large and interesting spiders. As a formation, Dundee is not particularly exciting, and one may feel a bit spoiled in collecting in other formations in the Devonian. Still, it is where I live, and the limestone seems to be the landscaping material of choice around here First up is a fairly well preserved tabulate coral, "front and back."