Pond life - but what?

Pond life - but what?

Observation - Pond life - but what?. Description: I have no idea what this is. It came up during a pond dipping session. It is about 6-7mm in length and is facing to the right. It rarely stopped in one place for more than a second or so. This is the only sharp(ish) photo out of about 20 attempts. After l

I have no idea what this is. It came up during a pond dipping session. It is about 6-7mm in length and is facing to the right. It rarely stopped in one place for more than a second or so. This is the only sharp(ish) photo out of about 20 attempts. After looking at it through a magnifying glass, the nearest thing to it that I had ever seen is much bigger - the King Crabs on the eastern seaboard of the USA. Like them, this seemed to have a carapace-like shield over its back with perhaps six or eight legs working away underneath it. Some kind of amphipod or copepod?