Moths & butterflies (Lepidoptera)
Lepidoptera, with over 1800 species, form the third largest order of insects in New Zealand after beetles (Coleoptera) and flies (Diptera).
Although our fauna is not diverse by world standards, and is especially poor in butterflies (only 13 native species currently recognised), it is extremely important globally for its high proportion of endemic taxa (about 90% of all species), and the presence of ancient, relictual groups, some rather richly represented (e.g. Micropterigidae with at least 16 species, and the endemic family Mnesarchaeidae with 14).
New Zealand shares with Australia and New Caledonia an unusually high proportion of species with detritivorous larvae (i.e. larvae feeding on leaf-litter, dead wood and/or fungi), and the second most diverse family of Lepidoptera here is just such a group, Oecophoridae (nearly 250 species, compared to just 86 for the former USSR, a land area 80 times as large). Tineidae (over 100 species) and Psychidae (over 50 species) are also well represented. Such recyclers of nutrients in our forests and shrublands undoubtedly play an important ecosystem role, but unfortunately these groups are among the most neglected and difficult taxonomically. Many detritivorous moths from overseas are well established in New Zealand and their effects on our native fauna (if any), such as through competitive interactions, are unknown.
Current research is focused on improving our understanding of these groups, their taxonomy, biology, distribution and microhabitat requirements. Information is presented as part of taxonomic revisions in the Fauna of New Zealand series.