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If it wasn't feasting on the xenia it could most likely be fine. They are scavangers and most likely won't cause problems, but if you keep an eye on it you can remove quickly if it causes problems.
It's in the sump for now. Until I get some sort of ID. It seemed to be hiding deep in the Xenia. I'll keep an eye on it. Xenia just came in to LFS from Fiji recently and was out of quarantine. If he's a good hitchhiker I want to keep him.