15/11/2025
Jackson found a Pūriri moth in our garden!
Isn't she beautiful ❤️
The puriri moth (Aenetus virescens), also known as the ghost moth or pepetuna, is New Zealand's largest native moth, found exclusively in the North Island. It is known for its dramatic life cycle, spending years as a large caterpillar (mokoroa) before a brief adult stage of only a few days.
Key Facts
Size: The female is the largest, with a wingspan of up to 150 mm (about 6 inches), while the male's wingspan reaches up to 100 mm.
Appearance: Adults are typically bright green with variable wing patterns; females usually have dark patterns, and males have white ones. Other color variations, including yellow and red, can occur.
Adult Life: The adult moth has no mouthparts and does not feed. Its sole purpose is to mate and lay eggs, living for only about 48 hours.
Nocturnal: Pūriri moths are active at night and are often attracted to artificial lights.
Life Cycle Summary
The puriri moth's life cycle is long and involves six distinct stages:
Eggs: The female scatters up to 2,000 eggs on the forest floor.
Litter Stage Caterpillar: After hatching, the tiny caterpillars live in leaf litter and dead wood, feeding on bracket fungi for two to three months.
Transfer Phase: The caterpillar then moults and moves to find a host tree.
Tree Stage Caterpillar: The caterpillar bores a distinctive "7"-shaped tunnel into the trunk or branch of a host tree, such as the pūriri tree or putaputawētā (marbleleaf). It lives in this tunnel for several years (two to five years on average, but up to seven years), emerging at night to graze on the callus tissue that forms around the entrance, which it covers with a protective silk web.
Pupation: Once fully grown (up to 100 mm long), the caterpillar pupates inside its tunnel.
Adult Moth: The pupa wriggles up the tunnel and protrudes from the hole, allowing the adult moth to emerge, usually between October and December.
Ecological and Cultural Significance
Host Trees: The caterpillars create significant damage to trees, which can weaken small ones, but most host trees survive. The empty tunnels are often used as homes by other insects, particularly wētā.
Cultural Value: Known as pepetuna or mokoroa by Māori, the moth has cultural significance as a spiritual messenger or "ghost of an ancestor". The caterpillars were also a traditional food source and used as eel bait.