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Here is a story about my worst collecting blunder yet. This happened about a month ago at this point, I am still embarrassed by this story but I thought it would be worth sharing for a few reasons. As many can agree, one of the biggest struggles in this hobby is the amount of space these fossils can take up. I live in a smaller apartment and the way I make this work is by trimming some of these fossils with a wet-saw. This has worked very well for me for years and does a better job keeping the fossils safe rather than the force of striking with a hammer and chisel. If I find something really remarkable, I don't risk breaking it in the field and I take it home to cut with the saw. I was cutting a disarticulated Trimerus sp trilobite from a boulder that I found in the Rochester Shale this winter, field picture here: I found these pieces separated like this and thought that this disarticulated cephalon went to this body. Cool find, my first Trimerus partials. But just in case there was some more fossil under that matrix I gave it some clearance until I buy some prep equipment. I cut the rock in two places to section out the thorax. Assuming that the cephalon above was associated with the body was my first mistake. My second mistake was not saving this rock until I had a chance to prep it. Since the remaining rock was a good sized chunk I decided to check for some Rochester Shale fossils A few hits with my hammer on the side of the shale revealed this.... Another Trimerus head sliced cleanly by the saw, just over 2 inches long (the size of my largest trilobite). Terrific. If there is any bright side to this, I think the cephalon is cut along the border where it would connect with the thorax. The picture above doesn't show it well, but the fossil is folded under the surface. It looks like this is where the second eye might be (about where my ring and pinky finger are pointing). At first I thought I sliced it in half, but now I am not sure. Here is everything puzzled back together as well as I could. Either way, a big lesson learned here. I am still interested to see how these connect with each other, or if there is any more in this matrix. Have to get some prepping tools now.

Hello all, In my investigation of the fauna of the Devonian Mahantango Formation, I have become quite interested in the trilobite Dipleura dekayi. I have not yet had the opportunity to encounter this bug on the field, but it’s size and strange appearance have draw my interest. From the sources that I have read regarding the Mahantango and Hamilton Group formations in Pennsylvania and New York, I have noticed that trilobites with a very similar appearance have been referred to the separate genera Dipleura and Trimerus. In Fossil Collecting in the Mid-Atlantic States, Jasper Burns seems to treat Dipleura and Trimerus as synonyms. However, Wikipedia (I am fully aware this is not the most reliable source) has separate pages for Dipleura dekayi and Trimerus dekayi. I have also heard more references to Trimerus when the specimens are found in the New York area and I vaguely remember a posting on the forum where the question of Dipleura vs. Trimerus was addressed but which post that was has escaped me. Here are the main questions that I have regarding this topic: 1.) Are Trimerus dekayi and Dipleura dekayi different valid trilobite species or are they synonyms? If they are synonyms, which would be the most proper to use? 2.) If Trimerus dekayi and Dipleura dekayi are two different valid species, how can they be differentiated? Does this depend on the region where the specimen was recovered? 3.) Are there other species of Trimerus present in the Mahantango Formation/Hamilton Group and how can they be identified and differentiated from Dipleura? Thank you in advance to all who view and comment on this post. I am very eager to learn more about Mahantango fauna and hopefully it will not be long before I find my first Dipleura/Trimerus in the field.

Yesterday, I was searching the Arctinurus layer of the Rochester Shale. Gorgeous day in Western New York. Here is the bench I planned on going through. If you look really hard in the middle and halfway down, you can see a Trimerus delphinocephalus. (Just kidding) I don't have X-ray vision and you can't see it because it wasn't exposed yet. A nice complete prone bug was waiting about 420 million years to see daylight again. This is what I first saw looking at me. I take pictures prior to extraction, you never know what can happen. It was sawed out and worked out well. Looks like it will be a quick clean prep with not much gluing. Hope I can post finished pictures in a couple weeks.