UFO???

[EdSnyder]

Need help with ID. Sorry I cant get a picture of this guy. I got up early for work today before the sun came up. I went into the living room, (completely dark), and switched on the overhead light and looked into my tank. I saw my Emerald crab right up by the glass. He wasnt alone. He had this thing buzzing around him. It went back and forth across the tank and the went around behind a big rock and dissapeared. If you have ever seen a water beetle in a freshwater creek, it resembled that. It moved so fast I couldnt get a good look. About 2 months ago I got some new liverock from the Keys. I havnt ever heard of any hitchiker like this.

 

[DeathWish302]

I've seen those when I took some sand from the Gulf Coast (St. Pete area). They looked just like FW 'water boatmen' and buried into the sand when you bothered them. They wouldn't eat some pellets I threw in the jar they were in. They died about 1 week after returning from FL. I would guess they MAY be predatory, but there isn't much for life near the shore where I was at.