The puriri moth is one of our most magnificent moths. It is the largest moth in New Zealand, with a wingspan of 15cms.
Despite its mammoth size you’d be lucky to see one because they only live for two days during the months of October - December. To avoid predators, they use the cover of darkness.
The puriri moth is the adult of their species. Most of the moth's lifecycle is spent as a caterpillar. After they have mated, the female will spread up to 2000 eggs amongst the leaf litter on the forest floor.
The caterpillars hatch and spent a few months feeding on fungi, then the young caterpillar (or mokoroa) will climb the tree, and burrow inside. Their preferred native trees are puriri, putaputaweta, makomako or lacebark. The caterpillar is eaten by ruru (morepork), käkä and robin as well as cats and rats.
They live on the sap of the tree, eventually causing its death and decay – hence the saying ‘he iti mokoroa e hinga pūriri’ (the little mokoroa grub fells a pūriri tree). After about 7 years living inside the tree’s trunk, the caterpillar pupates into a moth, then it emerges – briefly – to find a mate, and then dies.
Pepetuna, means 'eel moth’ perhaps because early Maori used puriri grubs as eel bait!
It could also be a reference to the fact that females spawn at a time when eels are migrating to the sea.
The puriri moth uses scent to find mates, it is thought that the male will let off a scent to say ‘come here’. The females don’t have a nose, so instead they use their antennae to smell. This is why their antennae are branched and feathered! The puriri moth doesn’t have mouthparts, so it can’t even eat during the two days that it is alive.