 A black stripe runs down it from its head and pronotum to the bottom of the thorax narrowing as it goes along, the males possess large mandibles for battling for territory and mates and can reach 24-65mm.A female will be 21-31mm, the larvae are a creamy yellow and feed on rotten wood.They reach around 25-36mm in length and are voracious eaters taking a year to reach the pupal phase and 4 months to pupate.