I should have taken a picture/video if it, but a very large assassin of mine. About the size of an acorn, was caught eating one of my Snow White mischlings. I had looked at the tank 30 min before, everything was fine. I looked back at the tank and the assassin had the Snow White which was breathing/struggling in its clutches. I quickly got out the net and separated the 2 but the damage had already been done, the assassin had taken a nice chunk out of him and he was unable to swim normally, so I had to dispose of him. I had never seen this with my own eyes, and was always a little hesitant to believe they could/would be able to catch and eat a healthy adult shrimp, but it is absolutely possible.