Rove beetles. Large, diverse group with many terrestrial forms. Semiaquatic taxa are usually shore dwellers, many taxa are marine intertidal. Adults generally have truncate elytra exposing half of the flexible abdomen; antennae usually 11-segmented; no protrusible vesicles; most with contiguous procoxae and 6-7 visible abdominal sternites; tarsi simple.

Larvae found in moist areas of adult’s habitats. Larval forms very diverse morphologically. Abdomen with 10 segments; first 6 or 8 segments similar in length and width, remaining segments progressively narrower and longer; urogomphi 1- to 3-segmented; 10th abdominal segmented may have cylinder-like anal pseudopod.