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In my Secret Santa gift last Christmas from @connorp I received (among other nice items) a very nice little hash plate from the Mifflin Member of the Platteville Formation (U/M Ordovician, Blackriverian, ~453 MY) from SW Wisconsin. The picture below is the plate as it was received and in my 12/20/22 post about getting it I said: “A great hash plate. I already see two or maybe three different trilobite types with a couple of them tantalizingly partially buried and an interesting gastropod that I am not familiar with. I think a little prep work will make this even more spectacular. As an added plus, it represents my first fossils from the state of Wisconsin.” I finally got around to doing the prep I talked about and spent a little time exposing some of the more prominent fossils and giving it a gentle going over with air abrasion to bring out some of the features. I think it looks even better than it already did and I was even more impressed with the wide variety of fossils on the small section of rock. Below is the cleaned up plate: Here is a collage of the plate just turned at different angles to the sunlight in case it helps to bring out any features: There are hundreds of fossil fragments on this one small piece of rock, but I want to highlight the top couple dozen specimens. With the help of some TFF members via previous posts and replies in a couple of ID threads I put out (thanks @Tidgy's Dad, @connorp, @piranha, @minnbuckeye and others), I have identified several trilobites, brachiopods, gastropods, ostracods, bryozoans, and a crinoid and want to show you this wonderful diversity in such a small space. If anyone sees changes to my ID's please feel free to chime in. Some will be very specific ID's and some will be a bit more general. The picture below is the key to where each of the numbered specimens is on the slab (see number in upper left of each specific picture). We will start with the trilobites. Although each is only a partial, there is enough present to get a pretty specific ID on most of them. All are new genera or species in my collection. Here are the brachiopods: Here are a couple of specimens of a really neat gastropod which was new to me. So often it seems Paleozoic gastropods are just internal molds or rather plain forms, but this first one is very nice. Here are a few bryozoans and one very small horn coral. There were several of these small corals, I'm not really sure of the ID, I didn't research them much yet. Just a couple of small crinoid columnals were found. And last but not least are the ostracods. I am used to small ostracods (which some of these are) but there is also this one form that is huge (by ostracod standards) coming in at about a centimeter long. At first I thought they were brachiopod fragments until I looked at them closer. These things are the size of a kidney bean! Note the scale difference between the Eoleperditia and all the others. Most of my ID's are questionable as I was using a reference that is for the immediately overlying Decorah Formation until I can find a listing for the Mifflin Member. OK that is everything for now. I hope you have enjoyed the wonderful diversity of this small slice in time. With a little more investigation, I may yet tease out a few more specimens worthy of an ID. Thanks for looking. Mike

Once again hunted a bit after work. Found some crinoid pieces, a trilobite, hundreds of gastropod casts, and what I believe is a part of some type of trilobite in matrix. Any ideas?

It'd been awhile since I last joined the Austin Paleo group for one of their field trips, so I was excited to finally catch back up with them at some sites about 3 hrs up north. The plan for the day was to hit up Brady and Santa Anna, but the weather forecast had put things into question. Originally, I had some rather ambitious sites lined up in the Llano Uplift afterwards. The rainy conditions, however, meant the river would be a little too high for walking. After a peaceful morning drive under the guiding light of the full moon, I pulled up to the first location where I was relieved to see things weren't canceled, and Melvin plus the gang were already crawling along the slick exposure of Strawn Group shales (Desmoinesian Series). Upon stepping out of the car, I was suddenly met with a confusing mix of cold drizzly rain and warm gusts of humid wind. It wasn't unbearable though, and I was more so focused on catching up with some familiar faces anyways. The hunting proved a bit treacherous. The ground shimmered with newly formed mud mounds that loved to stick under your shoes. Although it wasn't nearly as bad as wet Grayson/Del Rio matrix (Waco Pit), it was still a strenuous activity, having to climb the hillside in my new platform shoes. Things started off a bit slow. The weather dampened the mood, but with enough effort, people started making some decent finds. I was hopeful to prove my crinoid crown from last year was no fluke, so I went straight to business, closely inspecting every rock for anything out of place. It was a challenge to look for details through the mud. Nevertheless, it was a rich site and everyone kinda knew the spectacular finds would roll out one way or another. After an hour and a half of looking at hash plates and broken brachiopods, I found the first keeper. Especially since it was covered in mud, this guy was tough one to notice. I think 9 times out of 10 I would have walked over it. A small, smashed crinoid crown and arms Nearby I also picked up a small crinoid cup which are always fun to find. As we were wrapping up, I took a gamble wiggling out a mucky mass of what looking like a crinoid arm erupting just from underneath a bigger rock. It didn't take long to figure out it was most definitely a large crinoid crown. The species is hard for me to say, so I am open for suggestion. A large crinoid that took a bit of cleaning. The other side shows some arms, but there is a lot more matrix covering it. With all the rain, Melvin and Ed decided it was wise to skip what would have been a messy parking situation at Santa Anna in favor of an impromptu trip to the beloved Wilson Clay Pit of the Harpersville Fm (Virgilian Series). After about an hour of caravaning northbound, everyone gingerly parked their cars along the gravel margin. It took a bit of teamwork to set up some big rocks for a makeshift bridge across the mote separating us from the gate, but we pulled through. Others gave up a bit too early and decided wet feet for the rest of the day would not dissuade them from taking the shortest route across the puddle . Wilson was a good call as things were surprisingly easy to traverse once inside the quarry. All the rock fragments made for good footing. I had made a couple new friends who happened to be fossil forum lurkers. One of them was named Will, and I decided to help him out with finding some Pennsylvanian shark teeth. Once we located the right rocks, I tried to show him what to keep an eye out for. He was a fast learner and pretty soon we were both consistently spotting little pieces of Petalodus among other cartilaginous vertebrates. Sadly, I didn't find most of my cooler stuff until he was sick of all the hammering and ventured elsewhere to find inverts! The first keeper for me was a mess of associated Archaeocidaris plates and spines. Not nearly as pretty as those of the Brownwood Spillway, but still neat nonetheless. Archaeocidarid plates and spines Not long after, I made a rather unexpected discovery. I guess in the past I wasn't looking at each rock close enough. I had heard of Cladodont sharks being found in Wilson before, but never saw one myself. Over the course of the day, however, I found like 6 of them in varying condition. They are surprisingly common, but go unnoticed because they are usually so tiny. I have seen the species Symmorium reniforeme referenced in Wilson, but I am under the impression that these teeth are now classified as Glikmanius occidentalis. My favorite is the middle one below. Its white coloration makes it almost look like a modern shark tooth on the beach. Cladodont (Glikmanius occidentalis?) shark teeth. Surprisingly common in smaller sizes. "Deltodus" was the second most common shark of the day and I managed to snag one in near perfect condition. "Deltodus" Throughout the day I was really hoping to find a Petalodus as good as the one from last year, but alas it was not meant to be. Still, there were some decent ones that showed themselves now and again. One tooth has some really cool dendritic mineralization on the enamel. Best Petalodus ohioensis of the day. As I was writing the above excerpt on the dendritic Petalodus, I took a second look at it and just noticed a trilobutt on the back of the broken root! First Wilson trilo for me and it's on a Petalodus tooth go figure. I guess there's no other way I'd find one given my vertebrate fixations Trilobutt on Petalodus! It was about sunset when I left. Of course I was one of the last ones there along with Ed and Melvin. I need to work on my controlling my fossil hunting urges for sure. Anyways, it was a nice day for a hunt and definitely something I needed. The 3 hour drive back felt like nothing as all I could think about was what awaited me the next trip out. Thanks for reading!

Hello, I found this rock in an ephemeral stream bed with what I think is an ammonite and crinoid head in the same rock. I'm somewhat familiar with the local geology and fossils but not 100% sure. It was found in Columbia MO in what should be part of the Osagean series of the Mississippian. Most common rocks in the area are limestone, chert, and dolostone; crinoids are extremely common. I'm a lot less confident on what I think is a mold of a crinoid head (second fossil pictured). I just hope it's not a chert nodule. Anyways I would love to hear other opinions to confirm this. Thanks!!!!

Busy weekend with a fossil forum meetup at DSR in Madison County, NY and a Buffalo Geological Society trip to the LaFarge Lockport Quarry which is in the Lockport Dolomite. Very fun meetups with both groups and plenty of great finds to go around. I got pretty lucky with the fossils I found at DSR, including what I believe to be a very small pyritized complete crinoid but I could be wrong. I'll add the suspected crinoid pictures to a separate comment, looking for input from community members. I'll start out of order with Lockport since I did not find many fossils. Just a few nice corals, not sure what the ID would be for these yet. 1. Tabulate coral in matrix, no scale. This was approximately 4-6 inches in length. 2. Two different coral specimens I was able to take home Fossils from DSR: 3. Disarticulated Dipleura trilobite. One of my favorites 4. Tornoceras cephalopod fossil. 5. Paleozygopleura encrusted by bryozoa, great preservation 6. A few of the Greenops trilobites I found, some may be complete under the matrix. Meant to put these in a separate comment, but they are here now. A few too many pictures, but the different saturation and lighting helps view the fossil better. This would be my first complete crinoid, very excited about this one if it is. The larger chunk of shale that I found this piece in had other crinoid partials in it as well.

Wondering if this is Ancyrocrinus bulbosus? Found in the middle Devonian in Erie co. New York. Moscow formation I think.

Howdy all, Been finding some crinoid stems in my usual spot in the Drakes Formation and I'm wanting an ID on them. They look similar to stems from Agaricocrinus americanus from the Carboniferous of the eastern U.S., though they were found in an upper Ordovician deposit. Any ideas?

A few days ago I took a trip to view some exposures of Ordovician aged rock along the Mississippi River. I had decided afterwards to take a little detour and stop by a fairly popular exposure of Mississippian aged Golconda Formation outside the town of Anna, Illinois. There is rock exposure along both sides of the road here. I was careful, and decided to park further down along a gravel road. A lot of material at this site is weathered out, and easily collectable. I flipped about every rock I saw as I walked up to the exposure, and the first rock I flipped had a nice blastoid on it that looks to clean up nice. I didn't use any tools here, everything collected was just picked up loose. I found a few more nice Pentremites blastoids. This next one is probably the largest Pentremites I've found in Illinois. It was huge! Here are the two compared next to each other. I believe they are both Pentremites pyriformis. I found a few nice crinoids as well. I almost couldn't believe what I saw when I spotted this first crinoid! A very small and dirty Phanocrinus crinoid. The next one I found was on a rock I flipped over, and better shows the bottom calyx plates. This one unfortunately wasn't complete, still not too shabby. There were alot of bryzoans and brachiopods weathered out. I did take a small handful of Archimedes spirals. Last find was a small block with a trilobite pygidium on it. This was a nice little stop. It was very easy to collect as well.

I stopped by a Mississippian aged road cut in Illinois today while driving on my way home. I found some crinoids, and I believe they are all Phanocrinus formosus from the Golconda Formation. I appreciate any input. I apologize, my camera cannot capture the best images of the smallest specimen.

Yesterday I was able to take a trip to the Silurian Racine formation of Southern Wisconsin. This site was easier than others due to the clear stratification, and I was able to see some of the reef overlay and underlay. finds included: my first dolomitized crinoid calyx, a nice fez-looking coral, some Bumastus trilobits, and what looks like a Cornulites impression? I’m curious if anyone has thoughts on the circular impression with calcite growths in it- unsure if it‘s an imprint or just a gap with mineral growth. Included a fun extra picture of old and new critters paired together.