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On December 4 my mom and I traveled to the well-known Seven Stars Quarry of Seven Stars, PA a second time (#1 in a post soon!), and our goal was to find more trilobites and cephalopods. This locality is Middle Devonian Mahantango Formation shale, full of a bounty of species. We had found many Dipleura and Greenops on our previous trip, as well as the cephalopods Michelinoceras and Bactrites. Many trilobites that I found were pyritized, the golden Greenops and red Dipleura. But surprisingly, Eldredgeops is absent from the site! Nearly every Mahantango locality includes Eldredgeops rana in the fauna! It seems that the larger and more powerful Dipleura outcompeted Eldredgeops in the large predatory trilobite niche. I wanted to learn more of why Dipleura is everywhere, so I picked through a 7-foot vertical shale hill on the hunt for more clues. I grabbed a large sheet of rock with well preserved Chonetes brachiopods on it and moved it into a bucket. Then I looked back at the spot where it was and sitting there was a small, nearly complete trilobite (above). I thought it was a Greenops at first. I wrapped it in some napkins from the Rutter's nearby, because two chunks were breaking off and it needed protection from further damage. When I got home, I got out my New York Devonian fossil guide (because it's helpful for many Hamilton Group fossil IDs such as Mahantango fossils) and searched for Greenops in the trilobite section. I observed the diagrams and descriptions, and after I checked my fossil for features, I determined that I had not a Greenops but a Bellacartwrightia. This is a rare species outside New York (mainly at Penn Dixie FP), which explains why I had only found one in my multiple trips to similar sites with fossils like Penn Dixie's. I was naturally excited. But as time progressed from Dec. 4 to today, I began to get suspicious of my highly thoughtless conclusion. I had no backup species to think about, if I had made a wrong ID. Today I was reading a paper on a group of phacopids and realized that a diagram of a pygidium on the paper was almost identical to my trilobite. I came to a much more acceptable conclusion: I had a species of Asteropygine trilobite. Annoyingly, I had no knowledge of what genus/species it is AND I had accidentally posted this cool bug as an entry for IPFOTM. I need to redo it. But, overall, a rare trilobite in Asteropyginae is awesome. What a trip!