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A family of amateur fossil hunters from Utah -- the Gunthers -- found this fascinating fossil in the Spence Gulch shale part of Utah in 1992, and shared it with Richard Robison at the University of Kansas. The mystery of what it was went unsolved for nearly 30 years, until a team at Ohio State uncovered the telltale circle that showed the creature had attached to a shelly surface via a basal disc. It's the earliest/one of the earliest known specimens of a mat-sticker making the evolutionary move to attaching to a harder surface--a leap that makes some of our modern-day echinoderms, including sea cucumbers, possible. They recently published their findings in the Bulletin of Geosciences but this discovery wouldn't have been possible if the Gunthers hadn't found the fossil in the first place. Just fascinating stuff. (story here: https://news.osu.edu/scientists-discover-evolutionary-link-to-modern-day-sea-echinoderms/),

I got back last week from a two week collecting trip in Idaho, Utah and Wyoming with my wife and our two friends Bill and Jean. In addition to collecting, sunstones, topaz, agates and fluorescent minerals we collected Cambrian,Silurian, Jurassic, Cretaceous and Eocene fossils. We collected trilobites outside Delta, Utah and Liberty, Idaho, Marine fossils in Emigration and Riley Canyons in Utah and fossil fish in Kemmerer, Wyoming. The results of the trip was 15 boxes shipped home and many hours of preparation ahead of me. My friends came away with 13 boxes of fossils. If anyone wants tips for successful shipping of fossils please PM me as I learned a lot shipping with both USPS and UPS. Perhaps a post about shipping might be valuable. Photots from the trip will be posted at the end. Our first fossil excursion was to U-Dig quarry. Within ten minutes of arriving my friend Bill found a beautiful Asaphiscus wheeleri molt. That was the start to a great day of collecting. By the end of the day my wife and I had a table covered with trimmed examples of all of the common trilobites. The highlights were Bill's Asaphiscus, a huge 2 inch Asaphiscus I found, two brown trilobites and a 1 3/4 Asiphicus my wife found in the discard pile as we were getting ready to leave. We left with four flat rate boxes in total. After collecting in the Delta area for fossils and minerals we went back to our condo in Park City, Utah and visited Emigration Canyon for Jurassic marine fossils in Salt Lake and Riley Canyon, near Jericho, Utah. We found some brachiopods in Emigration Canyon but the fossils were not abundant. Our next stop was Riley Canyon for agatized horn coral. After a hike that resulted in a 3000 foot elevation change from 6000 to 9000 feet we eventually found the horn coral site. It wasn't what I expected. The searching involved looking for loose rock on the mountain among vegetation. While we found pieces of red agate, the agatized horn coral was elusive until my friend Bill found a nive 3 inch horn coral. We continued to search the area with little luck. By the time we left I found one small agatized horn coral and several chuncks. I did find one fossil that was mostly buried in matrix. At the time I thought it was a horn coral but imagine my surprise when I started prepping it and found that it was a large brachiopod. I do want to say that Riley Canyon material is one of the hardest materials I've ever prepped. The matrix is very stick and doesn't want to release from the fossil. It is also extremely difficult to remove with micro-abraision. Our next excursion was to Spence Gulch outside of Liberty, Idaho for Cambrian fossils. Fortunately I had read many different directions to this locality, otherwise we wouldn't have found it. It was a solid miles walk from where we had to abandon our rental vehicle. My wife and I found the matrix at the site to be very similar in consistency and friability to Spring Creek material in Alden, New York. You definitely want to bring cyanoacrylate (super glue) or some other stabilization agent as well as foil to wrap your fossils in so that they dry slowly. Otherwise your prized fossil may be dust by the end of the day. As soon as we arrived at the site I found what looks like a partial Zacanthoides trilobite. By the end of the day our party had found three partials. Bill and I started the morning climbing the slope and excavating pieces where someone had exposed a flat section of rock outcropping. We were rewarded with trilobite pieces and a few hyoliths. We then moved to the base of the outcrop and started splitting small pieces of shale. By the end of the day we found about 20 complete Achlysopsis (at least that's what I think they are). By the end of the day we had a good representation of the Spence Shale. Our last fossil excursion was to Forum member Sseth's fish quarry in Kemmerer, Wyoming. I want to start off by saying that the people working at his quarry are some of the nicest people I have ever met. They were very friendly and always checking in to see if we were having a successful trip. If you ever make it to Kemmerer to collect I have the following pieces of advice. Visit Fossil Butte National Monument Visitors Center first so you know what things look like. Bring boxes and packing material. Bring lots of water. Four people can drink a case of water by early afternoon. Bring sunscreen. Be ready for the dust. You will be covered in dust as will the interior of your rental vehicle or personal vehicle. We had such a good time at Sseth's quarry we actually went back a week later for another day of collecting. We had a lot of fun at his quarry. We came away with many individual fish and several plates of multiples. Most of the fish were larger than three inches and we came away with at least five different species of fish. Our largest fish were a 10 inch Diplomystus my wife and I extracted from a very large rock and an 8 inch Phareodus my friend Bill found in the discard pile splitting discarded rock. While we were there Sseth was excavating a turtle and while excavating it they found a second one. Photos will follow.

One more to post to see if someone more knowledgeable than me can verify. These were collected from Spence Gulch. I think that the first and second ones are Amacephalus idahoense. First is about 1-1/4" long and second is about 3/4" long. The third trilobite is very small at about 1/4" long bit looks to me like Zacanthoides idahoensis (I sure wish that one was full grown). Preservation on these is not the best, but you take what you get and these are my first Spence Shale fossils.

Recently collected these trilobites at Spence gulch along with a few more. The all seem very fragile. 1st picture is of the trilobite and second is the cast. Anyone experienced with these and have any ideas about what to do to prep from here? I am concerned about doing more damage than help and was just considering putting a light coat of PVA on them as is. I think these are Amacephalus but not sure what species.