What ate my peppermint shrimp?

[gsar]

I'm trying to figure out what might have eaten 3 out the 4 peppermint shrimp i put in my 75 gallon.

A while back I got them to clean out the aiptasia in my sump and they did a good job. After they finished I moved them into the display and about a week later three went missing. I have the following fish in there.

Pair of tomato clowns
One coral beauty
One chromis
One lawnmower blenny

No other crabs (except little hermits) and I've never heard the sound of a mantis. Actually had a cleaner shrimp in there for 6 months without any issues before i moved it to different tank.

Anybody ever have a problem with tomato clowns dining on peppermints? I haven't heard any of those fish being a problem.

Greg