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A friend uncovered this oddball today in the Late Ordovician (Sandbian) of eastern Missouri, in the uppermost part of the Plattin Group (a Platteville equivalent) or possibly the lowermost part of the Decorah Group. He's been finding a lot of weird fossils in that zone, including articulated cyclocystoids, but this one I'm at a loss on. Too wobbly for an orthoconic cephalopod, too much space between calcite elements for a crinoid column. Given the size, is machaeridian a possibility? What other ideas should we be considering?

I found this chunk of shale poking around a bluff side a while back near Lilydale Park in Minneapolis, MN. The fragment pictured is translucent and is slightly concave, it reminds me of a cheek plate but Im not sure. I'm new at this so I'm pretty clueless, I appreciate any help.

Does anyone know of deposits other than the LeGrand crinoids where each species is preserved in a different characteristic color, all on the same slab? We have this kind of thing in the brachiopods and trilobites of the Decorah Formation (Late Ordovician) here in Missouri, which is what got me thinking about it. But I've never seen a report summarizing other cases of this phenomenon, and as I think about it I'm not sure I can name any others. Can you? Brachiopod photo info: A= Zygospira B= Rafinesquina C= Doleroides 1 = Isotelus, rusty brown 2 = ?Achatella, light gray. Highway M near Antonia, Jefferson County Decorah Formation, Late Ordovician, ~450 million years old

Hello, bug lovers! I found some pretty cool trilobites this last Sunday at my favorite road cut in Wisconsin. Since I'm a bit of a noob with bugs I'd appreicate some help on IDs and a confirmation on the formation. I think this is the Platteville formation. But it could be Decorah.....? @piranha Sorry for the pics in advance. Lol Found as is. After a bit of prep. Gabriceraurus mifflinensis? Ceraurinella scofieldi (possibly more thorax)? Continued..........

While I was looking at a recent post here on the forum trying to help someone identify a Lepidodendron tree root I realized I had found something similar to Lepidodendron bark that I had just assumed was a piece of coral since I found it near other aquatic fossils. I found is somewhere near Decorah, Iowa (I don't remember exactly where). It's a bit worn, but does anyone know what it is?

I have a few hash slabs I use for educational purposes, and I'd done a couple of events recently, so I was taking a look at one of the slabs and noticed this small fossil. It is approximately 6.5 long by 3 mm across. The shape is roughly triangular, and the cross section may be triangular (it could be a V-shaped "sheath"); unless it is incomplete or collapsed, it cannot be four-sided. It is not perfectly symmetric, but slightly curved and lopsided (although the skew of the keel could be a preservational artifact). Both exposed surfaces have linear markings, so that it looks vaguely segmented, but on closer inspection the lines seem to mark the edges of long narrow "scales" which appear to be slightly imbricated. The hash slab was collected last spring from a spoil pile left by house construction on the Mississippi River Boulevard, St. Paul side, a few blocks south of Summit Avenue. I know it is Decorah Shale, but I can't provide more detailed stratigraphy. I assume it is from the lower third of the formation, based on geography. (The scale bar in the photo is mm-scale.) The object doesn't look like any of the usual suspects (coral, bryozoan, brachiopod, bivalve, nautiloid, snail, trilobite, echinoderm, trace fossil). It shares some aspects with conulariids, but the texturing does not look like discrete rods, and it doesn't appear that the cross-section could be four-sided. The only other thing that came to mind is a hyolith, but do hyoliths have this kind of texturing when well-preserved?

Are there still any good sites for the Decorah Shale in the St. Paul area? Shadow Falls has exposures, but they are not productive (only small bryozoan fragments, small brachiopods, and the occasional small trilobite fragment). We used to find large burrow casts and recepticulites at Lilydale Park, but it is closed permanently. Are there any other sites that yield the same kinds of things?