While New Zealand has 24 species of butterflies, the overwhelming majority of the Lepidoptera order found here is comprised of moths—at least 1700 species, 90 per cent of them found nowhere else in the world. They range from gossamer-thin, delicate beings to bombastic, whirring machines of the night. Some are even flightless. Moths are diverse; mostly nocturnal, many diurnal, some vibrant with bright greens or yellows, some—such as the primitive Izatha taingo—infused with the colour of their lichen-clad surroundings, imperceptible to predators until they move.

Many species are host-specific, a feature which has been to their detriment in the modern world—Archyala opulenta larvae can grow only in the dung of the endangered short-tailed bat, and Houdinia flexilissima larvae are found only in the thin stems of an endangered rush-like plant, Sporadanthus ferrugineus, which is confined to just three wetland sites in the Waikato.

Generally speaking, moths can be described as creatures of the night which hold their wings horizontally when at rest and possess feathery vibration- and pheromone-sensing antennae with tapering ends. Butterflies typically fly during the day, fold their wings together at rest and have smooth antennae which terminate in clubs. But the terms moth and butterfly are not recognised in scientific classifications and many species in the Lepidoptera order defy this common description. New Zealand’s ensemble is no exception: Some moths, especially in the alpine zones, are brightly coloured and fly during the day, and some of the butterflies would be lost in collections with their muted and unremarkable wings.

“One way to look at it,” says South Island entomologist Brian Patrick, “is that butterflies are just a few sophisticated, highly evolved families of moths. In some languages, the word for butterfly and moth is the same.”