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Take this proposal with a grain of salt. Posting it here because I didn't know where else to post it. References: https://www.mindat.org/taxon-8521156.html https://en.m.wikipedia.org/wiki/Callianassa https://pubmed.ncbi.nlm.nih.gov/36095673/ https://nathistoc.bio.uci.edu/crustacea/Decapoda/Neotrypaea californiensis/index.htm C. mortoni material I used in my research: Proposal:

Hello all, With the start of this month I have gotten back to doing some fossil prep. I am still very much learning but I am happy with how this one turned out. It's a Callianopsis clalamenis nodule from the Pysht formation of Washington State which I found this past January that preserves two sets of feeding and defensive claws as well as some disarticulated shell material. This prep was fun and I am excited to try another shrimp, they are a welcome break from working with very hard pyrite nodules from Yorkshire. Before prep: After about half an hour with the scribe, the first two claws are showing: After about an hour and a half: Finished. . . for now, until I smooth the matrix: I hope you enjoyed, Benton

@GeschWhat @Carl It has been cold, but the shrimp (callianassid) coprolite burrows I find have been relatively plentiful (more than decent sized shark teeth) with recent strong north winds and low tides. One puzzle to me is the variation in diameter of the burrows. Carl, our expert, believes the coprolites just sank and deposited in burrows (at another site I have found a few steinkerns with similar, sparser deposits. ) All of the burrows I have found on the Rapp beach have been cylindrical, or possibly pieces of cylinders (of course, this could be bias in my collecting, but I examine lots of stuff!) Usually the coprolite deposits are thicker on one side (the bottom?) of the burrow. If the burrows are truly made by the callianassids (Carl says no, others may argue) I expect the coprolites in the big burrows to be bigger than those in the smaller burrows. I have collected enough to get a tentative answer, but need to align by brightness for comparison photos (some burrows and coprolites are very light, some are dark). Here is what I have collected so far:

Was curious to see what had washed up on the beach. Weather was dominated by east winds and usually north winds bring in the most stuff. From my finds it appears that a lot of sand was deposited covering, sadly, most shark teeth. Did find several shrimp(?) coprolite "burrows" (which I had not seen much until my previous trip?) @Plax @Carl @GeschWhat Found only four shark teeth- - a medium Mako, a rootless Hemipristis, a sand tiger and a broken sand tiger (initially thought it was something more interesting, the break was polished smooth by the sand). Found my second piece of skate plate, with two teeth, but not as pretty as the first), and lots of small "whale bone". Pottery shards as well, but shells for the most part were sand covered with the presumptive teeth. Nice weather before the rains (and south winds which don't deposit much).