The stag beetle belongs to the family Lucanidae, a group of beetles known for their distinctive mandibles (jaws), which in males are often dramatically enlarged and resemble deer antlers—hence the name "stag" beetle.

Key Facts about Lucanidae (Stag Beetles):

Appearance:

Males: Large, often 5–12 cm long depending on species, with oversized mandibles used for fighting rivals.

Females: Smaller, with shorter but stronger jaws suited for feeding.

Colors: Usually dark brown to black, sometimes reddish or with metallic sheens.


Distribution:
Found worldwide, especially in temperate and tropical forests. Europe’s Lucanus cervus (the European stag beetle) is one of the most famous species.

Diet:

Adults: Mainly feed on tree sap, nectar, or rotting fruits.

Larvae: Live in decaying wood, feeding on rotting timber for several years before pupating.


Life Cycle:

Egg → Larva (lives in dead wood for 3–7 years) → Pupa → Adult (lives only a few months).


Behavior:

Males use their jaws to wrestle rivals for mating rights, often lifting and throwing opponents.

Despite their fierce look, they are harmless to humans.