Lucaninae is a subfamily of beetles commonly known as stag beetles. They are characterized by their large mandibles, which resemble the antlers of a stag, especially in males. These beetles are found in various habitats, primarily in forests, and are known for their striking appearance and diverse sizes. Stag beetles are primarily herbivorous, feeding on decaying wood and plant material during their larval stage. Adults are often seen in the summer months, attracted to light. The subfamily includes many species, some of which are popular among collectors due to their unique shapes and colors.