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A few months back I won an auction from @sixgill pete and part of the lot was a bag of matrix from the Waccamaw Formation in Columbus County North Carolina. The Waccamaw Fm. is a marine sand and shell hash that has been correlated numerous different ways with a varying range of ages applied to it in the past, but as it is currently interpreted, it is Pleistocene in age (Gelasian and Calabrian Stages or Upper Blancan to Irvingtonian if you prefer the NA names) and found in South Carolina and southeastern North Carolina. The bag was chock full of molluscan goodies and I am steadily working through the identification of those. One thing that caught my eye amongst all the shells were these little saucer shaped bryozoans similar to Lunulites except that most had a little grain of sand at their center. They are small (generally 2-3 mm in diameter, largest one is 7 mm across), but there were several hundred of them. After staring at them under the microscope for long enough, I recognized that there were at least two different types in here. Here is a shot of my sorting tray with all of them in there. A quick check of the two great publications I have from the North Carolina Fossil Club gave me some excellent pictures but three different names. A check of WORMS showed me that only one of those names was currently accepted so I began my search to see what was what knowing full well that bryozoan identification can be difficult and involves a lot of terminology that I am not well versed in (I have to admit, when ID’ing my collections, I am prone to lump the Paleozoic bryozoans from a given locality in one container and just be satisfied with that). A search of threads on the Fossil Forum led me to a couple where they were mentioned, but no defining pictures or ID’s. Here are a few pictures of what we are dealing with and I will apologize right from the start for the poor quality pictures. I really have to get a better setup for taking microfossil pictures since I tend to deal with small stuff a lot. I have decent microscope where I can look at them, but it is not set up for pictures. These are the two more easily identifiable forms, the picture on the right shows two of the same species but in one you can see the sand grain that is the starting point for the bryozoan, it sometimes gets covered or lost in growth and/or fossilization. So, after gathering and reading through a bunch of references from the early 1900’s onward I think I have the correct ID and most current name, but am open to any suggestions from those familiar with these little creatures. At the very least, hopefully this can serve as a helpful guide to someone who may have come across these, but struggled to put a name to them. There is a great publication by Canu and Bassler (1923) called North American Later Tertiary and Quaternary Bryozoa which provides lots of information, plenty of descriptions and enough illustrations to find both of the forms I had recognized. Specifically, they identified a species called Cupularia denticulata from the Waccamaw Fm and its description matched the form on the right above (just to make things interesting, there was another genus of similar bryozoa called Cupuladria, yes, just one letter different – ugh!). From this publication I had a potential name for the two types, could see where the names in the NCFC publications were coming from, and just had to track down what had changed in the intervening almost 100 years.