Stag beetle is the name of a family of beetles in which some males have oddly enlarged jaws. These jaws look somewhat like the horns of a male deer and have given the beetle its name. In some cases, these “horns” are nearly as long as the body of the insect. A common American species is the giant stag beetle of the Southern States. It has mandibles (jaws) 1 inch (2.5 centimeters) long and a body 11/2 to 2 inches (3.8 to 5 centimeters) long. The pinchingbug of the Eastern States is a stag beetle that flies by night. Adult stag beetles eat sap and honeydew. The eggs are laid in cracks in the bark of dead, decaying trees. They hatch into soft white larvae called grubs.