Rainbow Stag Beetle Notebook

The Rainbow Stag beetle gets the name from its unique colouring, which appears to change colour when looked at in different angles and in different light within its also unique, metallic-looking body. It is native to Japan, New Guinea and northern Australia. Metallic green and purple body, very rarely is either colour absent but several dark blue specimens have been recorded, and rare examples that were very dark in colour. A small percentage of non-teneral adults displays a shift in colour to either increased red or green.As an expression of percentage of total length, male mandibles vary between 19 - 32 %, irrespective of beetle size. Named after the strong, antler-like, curved mandible jaws. These are notably longer in the male than the female. They are nocturnal and sometimes attracted to lights.The males 'antlers' are used as levers during conflict. Each tries to pass them under the rival's body to raise and dislodge them. Males may adopt a threatening position stance by rising up on the mid and hind pairs of legs, with forelegs outstretched and mandibles working like scissors.Stag beetles are mainly vegetarians. Adults feed on nectar, young leaves, sap and fruit.