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Hi, I have made a poor post on this before, Hopefully this will work. I apologize in advance if the photos are huge. If there is a way to control that, I'd love to know it! I find these bug butts in my Dundee location near Sylvania Ohio. The first two are what I have been calling Dechenella planimarginatus (Type 1). They are by far the most common trilobite in the places I am looking. The third photo is of another type (Type 2). These are not rare here. I have only run across 3 parts not belonging to one of these two. The differences I'm noting are: Type 1 has a squared off end often showing a slight indent/rise at the tip. The axis is somewhat squared off at the tip, and it broadens fairly rapidly. There are three rows of axial lobes, including several up the center. I am able to see them protrude slightly dorsally; very slightly. The ribs are more widely spaced/less numerous than type 2. Conversely, type two is narrower towards the tip, with the end rounded. The axis is near pointed, and widens more slowly as you move up the axis. The ribs are numerous and closely spaced. The axial nodes are very slight, and there are none up the center of the axis. I should have photographed with a ruler, but for what it's worth, I have found type 1 parts quite large, suggesting an animal maybe 4-5 cm. Type two is always smaller than that. Not sure what other pieces of information might help. Thank you for any assistance you could provide.

I’ve spent about a year now combing through PA’s Mahatango, attempting to collect all of the trilobite fauna present in the formation. At this point I have all but one, Odontocephalus being the only that’s eluded me thus far. A big thanks to @Dean Ruocco for showing me around and in general refining my craft man. IMG_0717.MOV

Hey everyone! The other day me and a few other experienced collectors spent the day out in the Mahantango formation. After moving a literal ton of material we each came home with about 3 or 4 complete trilobites and plenty of other neat associated fauna. I found 2 different specimens that are incredibly interesting/rare a complete trilobite, Dechenella (I have to take the head off the counter part and glue it back onto the body after prep it will be fully complete.). This means I have a complete specimen of every species of trilobite in the Mahantango except the elusive and rare Neometacanthus and Monodechnella. The other specimen I found was a Phyllocarid valve. I have never seen Phyllocarid material in the Mahantango but It makes sense that they occur in the Mahantango. Let me know what you think.

This might be a job for @piranha This trilobit looks a little different to me than the typical Eldredgeops. Maybe Dechenella lucasensis? I didn't realize how poor the photo quality was until I cropped it. I can take more photos under the scope if necessary. Silica Shale, middle Devonian (Givetian), Paulding, Ohio. Scale in cm/mm. This one seemed different as well.

Interesting how something you read now can cause you to go back and have a look at something you put aside long ago because you did not think it was all that good or all that special. Last week Devonian Digger made a post "Trilobite in Need" This post got my interest because I did not realize any type of Dechenella was found at Penn Dixie. It got me to thinking that I should check out a box I had that contained what I believed to be a number of less than perfect greenops from Penn Dixie. I had put these away over the years as only being worth prepping on a rainy day and after I am caught up. I am way too far behind in my prepping for myself and other people to even think about prepping what I know is not going to be complete or at least better than my current display piece of that species / locality. My current best greenops is about 95% complete but a little distorted. A quick sort through them and this trilobite jumped out at me...... I had originally thought it was a damaged juvenile Greenops and was not likely going to be worth the effort that it would take to put it back together and then prep down from the top. You see the trilobite was split between two pieces of matrix and the front of the glabella was damaged and its genal spine was missing. I had found this at Penn Dixie in the summer of 2015. Here it is as I had put it away two years ago Note that I had originally trimmed the top piece in the field to reduce the carry back to the car weight. Those of you that know me realize that I take my saw pretty much everywhere. The good old boy scout in me "Always Be Prepared" So this morning, I got out my dremel tool with a diamond cut off blade and trimmed the top half of the matrix down to a manageable size. When you do a top down prep you want to remove as much of the upper matrix as possible before gluing the parts back together. The more matrix you leave the longer it is going to take to get down to the trilobite again. It is actually quite worrisome when you take an exposed trilobite and cover it all back up in the hope that the end product will be better than what you started with. Here is the trimmed piece of top matrix back in place. Seeing that the two parts had been separated for about two years they fit quite well. I used a thin non gap filling cyanoacrylate to do the bonding . Which I clamped for a few hours. Note that I mark the boundaries of the bug with a black Sharpie. Usually I put an "H" or "T" to let me know the orientation but I could still see part of the bug so this was not necessary. Next comes the boring part of scribing down to the approximate area of the actual trilobite . This was accomplished with a CP 9361 until I got close and then a German Pferd MST 31 with a fine stylus to get closer. The Pferd has a very fine stylus and a very high cycle rate (60,000). The scribing process took about 10 minutes After about 30 minutes of air abrasion here is where we are in the process As you can see the air abrasion of the bug is now complete. COMCO unit using 15 PSI .015 nozzle and 40 micron dolomite under 20x magnification. I am now at the point of deciding how much if any restoration I will do to this bug. It is cute and a species obviously that I did not have from Penn Dixie (or at least know that I had). It would probably benefit from some restoration So what is it. I am leaning towards it being a Pseudodechenella rowi. The dimensions of the bug are 14.7 mm long 8.7 mm wide at pleura 11.8 mm wide at tip of genal spines. Not being familiar with other specimens I suspect that this is a juvenille as the other examples I have found are twice this size. I am sure that Scott or Gerry will likely jump in to give me the correct identification. All in all not bad for something that until this morning was sitting in a shoebox wrapped in tin foil.