Click beetles are also known as skipjacks or jacknife beetles referring to their acrobatic behavior. When  flipped on their back they can snap a spinelike process into a goove on their chest with enough force to propel the beetle into the air and produce a clicking sound. This may startle a predator into dropping it. They belong to the family Elateridae of which there are  at least 965 species  in N.America. They are elongate, narrow in shape and parallel sided. Each end of the body is rounded with bluntly pointed elytra. They are usually brown or black with light markings. The antenna are close to the eyes, always sawtoothed and sometimes comblike. They range in size from 1/10 to 1 1/2 inches long.  Stag beetles get their name from the fact that males of some species have extended antler-like mandibles used to fight over females. These mandibles can range in size from large to very large and are sometimes branched. Many tropical ones are gigantic but around here they range from small to large in size (up to 2 5/8 inch long). The antenna are also distinctive with 10 segments and ending in a comb like club. These antenna are often elbowed. They belong to the family Lucanidae. There are about 24 species in N.America. Passalid beetles are also known as bess beetles and patent leather beetles and are in the family Passalidae. They have an elongate body that is nearly parallel sided. They range in size from 1 1/8 to 1 5/8 inches long. They are black and shiny and their elytra have lengthwise grooves.Adults and larvae communicate with sounds made by  rubbing body segments together.