Adults with long hairs on hind tibiae and other modifications for swimming; move their hind legs together like oars, like
Backswimmers do. Other aquatic beetles (e.g.,
Hydrophilidae) move their legs alternately
(6)
For further identification see
(4)(7)(2)(8)(9)(10)(11)(12)(13)(14)
*Ereboporus Miller, Gibson & Alarie 2009