rove beetle
    n 1: active beetle typically having predatory or scavenging
         habits

Rove \Rove\, n.
   The act of wandering; a ramble.
   [1913 Webster]

         In thy nocturnal rove one moment halt.   --Young.
   [1913 Webster]

   Rove beetle (Zool.), any one of numerous species of beetles
      of the family Staphylinidae, having short elytra beneath
      which the wings are folded transversely. They are rapid
      runners, and seldom fly.
      [1913 Webster]