Perhaps nothing tops the thrill of the hunt, but there are some species of trilobite I'll probably never get around to collecting in the field unless I win the lottery. Not long ago, I had posted a topic on The Fossil Forum requesting some trilobites to add to my burgeoning collection. Marc Haensel (MarcusFossils) was happy to oblige, and so he sent me a lovely package for me to collect from the little known strata of the "mailbox formation." With the exception of one of these lovely specimens, they are all Cambrian-age (543-490 mya). This would represent the oldest fossils I own. And here's a link to his eBay - he has some lovely specimens up for sale, he is courteous and fast. Best of all, unlike so many sellers on auction sites, he knows his stuff so never a worry about being sold fakes (a very big problem on sites like eBay). This will have to tide me over until the big quarry dig in a few weeks. On to the pictures! Colpocorphyes guichen. Ordovician - Traveusot Formation, Guichen, Îlle-et-Vilaine, Brittany, France Aphelaspis (Labiostria) westropi. Cambrian - Unit "H" Formation, McKay Group, BC Redlichia mai - Cambrian. Wulongqing Formation (Guanshan Biota) Chengjiang County, China Wujiajiania sp. Cambrian - Unit "H" Formation, McKay Group, BC Parabolinella sp. Cambrian - Unit "H" Formation, McKay Group, BC
Now that the course I was teaching is done, and the heavy rains are behind us, thoughts turn back to the hunt. The heavy rain system that lashed a lot of Ontario and western Quebec left a great deal of flooding. Fortunately, not as much here, but the rivers and lakes had been dangerously high, making any collecting near them too dangerous. But as it is the long weekend, Deb and I got out to Arkona for a five hour hunt. Overall, not a hunt that bagged the best specimens, but we weren't skunked either. This is the north bank. The photo does not show the proper scale for the bench I worked out. It was already started by someone else, but I was able to lever out two enormous slabs weighing maybe 300-400lbs each. The slabs were partially covered by overburden, so I underestimated their size until I started seeing a crack. But with a lot of grunting and levering with the pry bar, I freed them and rolled them down the hill to be worked on. Anyone who has worked the Widder shale before knows all too well that one has to go almost quite literally through tons of it to find a full Greenops. Instead, hundreds of moulted bits are quite plentiful. There are layers in the Widder almost entirely dominate by spirifer brachiopods, but they are trilobite-poor. Patience and a lot of hammer blows / rock busting can be rewarded. I was able to call first blood on a likely near-complete Greenops widderensis after a few hours working the slabs. Sadly, this one is tucked in the matrix (but can be worked out) and is missing a chunk of its right cephalon. But it seemed a pretty good day for nautiloids. Pictured above are three Michelinoceras sp. This one may be a bit more of a challenge to make out, but if you look closely you can see the spiral shape, with a bit of the texture showing in the upper left (the brassy, pyritized stuff). This would be a Goniatites, and a fairly large one for this strata. And last up: Deb found her complete Greenops (also tucked in matrix, but in better shape than the one I found). On the right is another semi-inflated pyritized Michelinoceras that I'll have to chip out of the rock. Pictured above is a before and after picture of the nautiloid I found, prepped with a Dremel. Came out fairly well, but this is as far as I dare to take it using an engraver. One day, air scribes and compressors will be needed! So that's about the long and short of the five hour Arkona trip. Below are some other odds and sods: Paid a visit to my local rock shop run by two very nice folks. I picked up these two Flexicalymene ouzregui (Ordovician) from Morocco's Anti-Atlas mountains. A busy brach hash plate from the Bois Blanc Fm fill out in my back nine. Nice big brach + impression from the same area. And lastly, another example of Anchiopsis anchiops - pygidium missing its pygidial spike. Lower right I suspect is just a worn and partially buried Eldredgeops rana. Below is a close-up of the Anchiops with some diagrammatic details provided by our Fossil Forum's resident trilobite expert, Scott. "Anchee," as I will call it, is a dalmanitid trilobite, and the way to tell it is by such an incomplete specimen would be the incised axial rings, shown by the arrows in the re-cropped photo below:
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Kane Faucher
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February 2024
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