glasswing moth with transparent windows in its forewings
- Size
- Length: 3–5 cm
- Lifespan
- 1–2 years
- Diet
- Larvae feed on native and introduced plants, often on underside of leaves. Adults feed on nectar from flowers during day. Transparent wings provide camouflage when resting on vegetation.
- Habitat
- Sunny, open habitats where they can be seen flying during day. Solar-powered moths that prefer light of sun to moon, with adults often visiting flowers in full sunshine, hovering like hummingbirds as they feed on nectar.
- Range
- Throughout North and South Islands in sunny, open habitats including gardens, forest clearings, grasslands and coastal dunes. Most common in warm, lowland areas with abundant flowering plants.
- Endemism
- Native
- Main Threats
- Habitat loss from forest clearance and urban development. Pesticide use in gardens and farmland which kills adults and larvae. Competition from introduced moth species.
- Population
- A specialised group of moths that have traded usual moth-fuzz for transparent windows in their wings. Often mistaken for butterflies or wasps.
- Conservation Status
- Not Threatened
Navigating the sun-drenched scrub with see-through panels. A moth that is transparent.
The glasswing moth is the transparent aviator of the New Zealand day-shift. Their anatomy is a biological marvel. By lacking the typical overlapping scales on large sections of their wings, they create a window-like effect that breaks up their outline against the shifting forest background, making them exceptionally difficult for avian predators to track in flight. A moth that disappears in the air.
This visible invisibility is bolstered by a potent internal defence. Many species are chemically protected, containing cyanide-based compounds they manufacture themselves. This rarity in the animal kingdom serves as a lethal deterrent, turning their brightly coloured red or yellow wing-borders into a moving warning for any would-be attacker.
As day-shift warriors, glasswing moths represent a state of high-energy equilibrium. Unlike their nocturnal cousins who rely on cover of darkness, these moths thrive in the full glare of the sun, requiring both a clever optical disguise and a sophisticated chemical arsenal.
Their life cycle is a definitive sign of a high-energy ecosystem, where the larvae often forage on specific host plants to sequester or synthesise their defensive toxins.
Their presence indicates a complex web of chemical warfare and evolutionary brinkmanship playing out in the brightness of the New Zealand wild. While not threatened, glasswing moths are vital indicators of botanical health of open forest margins.
The sun-drenched scrub is bright. The glasswing moth drifts, transparent wings catching the light, red borders flashing. A bird looks. The moth is hard to track. The bird gives up. The moth does not know it is a marvel. It does not know it is chemically protected.
It just wants to find a mate. To encounter a glasswing moth drifting through a sunbeam is to witness a survivor that has mastered the art of visible invisibility. The glasswing moth is proof.