Unlike many beetles, the soldier beetle elytra are soft and flexible rather than like a hard shell. Soldier beetles also tend to move slowly and not make a significant effort to escape. The reason for this is the presence of the compounds cantharidin within their bodies. These are bad tasting and toxic to the beetles' usual predators. Soldier beetles as adults are frequently found on open flowers where they feed on pollen. As the move between plants they might serve the roll of pollinator. The immature beetles are active grubs that inhabit the soil surface beneath leaves where they are insect predators.

There are several unrelated insects and even a spider with a very similar red and black pattern. The net-winged beetle shown at left is also toxic and because the patterns are almost the same they are termed Müllerian Mimics. With the same patterns, predators like birds need learn only one to avoid eating.