I purchased this as a supposed Silurian Megalograptus from Yunnan a while back. The seller gave me additional information that it came from the Devonian Cuifengshan Formation in Qujing, Yunnan, China. However, the genus Megalograptus is Ordovician in age.
I'm not really familiar with eurypterids, so maybe it's not even a sea scorpion. It certainly looks like some kind of invertebrate though. But maybe it's just indeterminate debris.
Image 1 - Measurement is in millimeters.
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