Stag Beetle

Lucanus capreolus

Stag Beetle

Lucanus capreolus

Harmless

Not dangerous

Harmless. A large male can deliver a pinch if you let him get a grip, and it is more surprising than painful. There is no venom and nothing that needs treating.

Size25–35 mm including jaws on a large male

MarkingsEnlarged antler-like jaws on males, sometimes a third of the body length · Females have short, much stronger jaws — the ones that can actually nip

WhereWoodland edges, parks and gardens with old or decaying hardwood, especially oak. Larvae live in rotting stumps and buried timber.

SeasonAdults in summer, chiefly late June to August

How to tell it apart

Enlarged antler-like jaws on males, sometimes a third of the body length
Females have short, much stronger jaws — the ones that can actually nip
Reddish-brown, glossy, with darker legs and head
Elbowed antennae with a comb-like club, which separates stag from other beetles
25–35 mm, and heavy enough to be audible in flight

Where you’ll find it

The eastern United States, from New England to Florida and west to the Great Plains. Several other Lucanus species overlap with it.

Woodland edges, parks and gardens with old or decaying hardwood, especially oak. Larvae live in rotting stumps and buried timber.

Adults in summer, chiefly late June to August.

How it behaves

The male's antlers are display and wrestling equipment: two males lock up and try to lever each other off a branch, and the size of the jaws settles most encounters without contact. They are strong but poorly leveraged, which is why a male's pinch is weak while a female's short jaws are the ones worth respecting. Adults are short-lived and feed little; the larvae spend several years in decaying wood.

You’ve found one indoors

Leave it. If you want stag beetles in a garden the useful thing is dead wood — a buried log or an undisturbed stump supports larvae for years, and tidying every piece of rotting timber away is the main reason they become scarce locally.

Common questions

Do stag beetles bite?

They can pinch rather than bite. Males have long jaws with weak leverage; females have short jaws and a genuinely firm nip. Neither is venomous or needs anything beyond letting go.

What are the antlers for?

Contests between males. They lock jaws and try to lift and drop each other off a branch. They are not used for feeding or against predators.

How long do they live?

The adult stage is a matter of weeks in summer. Most of the animal's life — often several years — is spent as a larva in decaying wood.

How is it different from a rhinoceros beetle?

Stag beetles have paired jaws that open and close horizontally like pincers. Rhinoceros beetles have fixed horns growing from the head and thorax that do not move at all.

Commonly confused with

Hercules Beetle Harmless
Rhinoceros Beetle Harmless

Keep identifying

Identify another animal from a photo or return to the Beetles guide.

Previous: Rhinoceros Beetle

Where this was checked

iNaturalist — Lucanus capreolus checked 2026-07-30
Missouri Department of Conservation — Stag Beetles (Lucanids) checked 2026-07-30

Last reviewed 2026-07-30. We identify, we don’t diagnose — what we can and can’t tell you.