Waikato Biodiversity Waikato Biodiversity
Features
Te Aroha Stag Beetle
Te Aroha Stag Beetle

Species feature: Te Aroha Stag Beetle

New Zealand’s beetle life is diverse. There are more than 4,500 named, native species. This is more than all New Zealand plant, fish, frogs, reptile, bird and mammal species combined. About 90% of New Zealand beetles are endemic to New Zealand meaning that they are found nowhere else in the world. The Te Aroha stag beetle is found on Mt Te Aroha and is a large flightless beetle with a black glossy body flecked with brown. The wing cases and the front part of the thorax often appear hairy.  Both the male and female have antler shaped mandibles (jaws). These are used to grasp, tear, and push food into their mouth.

The Te Aroha stag beetle is found on the ground or at the base of tree trunks at night and is probably a sap feeder. It has also been found under logs, in decaying matter and where good humus and leaf litter layers are present. They play a vital role in helping forest litter to decompose and are used to estimate historical environmental conditions.  Fossil beetles indicate past types of forest, which are evidence of a changing climate. 

Because they are under constant threat of attack, beetles have many ways to avoid capture. Ground beetles use chemical defences, and other secrete foul smells to ward off predators. Some species are camouflaged and blend in with the surrounding bark of trees.

Forest clearance has decreased the numbers of many beetle species and many more species have been lost. Although widespread forest clearance has now stopped, the continued fragmentation of forests may cause the larger, flightless, such as, the Te Aroha stag beetle, and less common beetles to become extinct.