Males are commonly about 30–55 mm long; females are smaller with short mandibles.
Fine-art photographic collection
Lamprima adolphinae
A beetle whose metallic surface can emerge green, blue, violet, red or gold without any paint-like pigment.
About this species
Rainbow Stag Beetle
Lamprima adolphinae(Gestro, 1875)
Information reviewed15 July 2026
Lamprima adolphinae is a New Guinean stag beetle famous for extreme colour variation and the enlarged mandibles of males. Larvae develop in decaying wood; adults feed on sugary plant fluids.
Taxonomy
Animalia · Arthropoda · Insecta · Coleoptera · Lucanidae · Lamprima
Accepted taxon. · checked 2026-07-15
New Guinea and nearby islandsBroad range and selected reference localities — not a complete occurrence map.
New Guinea and nearby islands
Lowland and hill forest with decaying timber and sap-producing trees.
Adults are active on trunks and feeding sites; larvae remain within rotten wood.
Larvae consume decayed wood; adults take sap and ripe fruit.
Solitary; males contest access to females and feeding sites.
What makes this species remarkable?
The rainbow colour is structural: microscopic layers in the cuticle interfere with light, so the hue changes with viewing angle and can vary dramatically among individuals.
A large male’s jaws are not designed for eating; they are levers used to grip, lift and overturn rivals, while the much smaller female retains practical biting mandibles.
Most of the life cycle is hidden inside decomposing wood, where a pale grub can spend many months converting fungal-softened timber into the body of a metallic adult.