I'm almost sure its a Whelk Snail! Whelk Snails are [FONT=Arial, Helvetica, sans-serif]carnivores and may attack and eat snails and scallops, they will definitely eat clams! I've not ever seen them attack coral, but I wouldn't consider them to be reef safe. The main differences between a Whelk and Nassarius is the spotted or a "tattooed" look on their "snout". [/FONT][FONT=Arial, Helvetica, sans-serif]Also, the feeler or eye stalks appear to be longer on the Nassarius snails, when you compare them to the Whelk's extended appendages. Whelks may "crawl" across the sand in your tank, but will not ever burrow under it. Whelks will usually spend all their time on rock structures, so coming in on live rock is also a clue.
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