Moths and butterflies are insects which together form the order called Lepidoptera, meaning 'scaly-winged'. The patterns and colours of their wings are formed by thousands of tiny scales, overlapping like tiles on a roof. These scales have been magnified 300 times.
At the last count there are around 1,880 named species of Lepidoptera found in NZ, including around 30 butterflies, while the UK with a similar land area includes over 2,500 species of moth though fewer than 70 butterflies. An important difference between the two regions is that in NZ over 85% are endemic, occurring nowhere else. Also, there are possibly over 200 species in NZ still to be named.
There are no simple rules for telling moths from butterflies and most of the differences are minor. Moths and butterflies share the same basic biology and have far more similarities than differences. According to Robert Hoare, entomologist at Manaaki Whenua - Landcare Research “butterflies are simply a group of specialised, day-flying Lepidoptera”, i.e. modified moths since they evolved from moth ancestors. However, in general the swollen tips of butterfly antennae distinguish them from day-flying moths. Also, commonly we associate moths with night flying.
As there are so many more species of moths than butterflies, experts split them into two groups, the larger or macro-moths and the smaller, or micro-moths.
There are around 680 macro-moths in NZ (900 in Great Britain), whilst micro-moths make up around 64% of NZ's fauna. Many micro-moths are very small indeed with a forewing length less than 4 mm, although confusingly a few of them are larger than the smallest macro-moths!
Moths vary greatly in appearance as well as size. For example, NZ's largest and best known puriri moth comes in a range of colours, from the typical pale green through yellow, blue to salmon pink. They also come in a range of sizes with small males having a forewing length of less than 27 mm while large females are up to 70 mm.
Other shapes are characteristic of different moth families, i.e. plume moths having delicate feathery wings. Colours and patterns also vary, some very bright and bold while others have wonderful camouflage.
Moths are very diverse in their ecology too, and can be found in surprising habitats, not just native forests, gardens, and farmland but also wetlands, coastlines and even mountain tops! You can also see moths at any time of the year, including mid-winter, although summer months are generally more productive.