Australia’s Butterflies: Some Background

Abstract

With only very few exceptions, interest in butterfly conservation in south eastern Australia has focused on members of four major endemic radiations, the trapezitine skippers, satyrine nymphalids, and thecline and polyommatine lycaenids. In part, this bias reflects the evolutionary interest of these insects as globally significant elements of the Australian butterfly fauna, but also that many of the constituent species/subspecies are both narrowly distributed and ecologically specialised, and so are prime candidates for becoming threatened as local environments are changed. Collectively, they are some of the most diverse groups of Australian butterflies and have diversified to produce complexes of daunting taxonomic and ecological complexity. This variety has generated considerable interest. They have long been attractive to collectors, so many are reasonably well known, at least in general terms. Several of the major components of these radiations are linked with equivalent diversification of southern groups of plants used as larval food plants: some Trapezitinae are associated intimately with Lomandra and, within the Lycaenidae, most species of Ogyris are found on mistletoes (and so are absent from Tasmania, where these plants do not occur), and Jalmenus on Acacia, the largest plant genus in Australia. Somewhat intriguingly, however, the vast genus Eucalyptus so characteristic of Australia’s forests and woodlands, is food for caterpillars of very few butterfly species. The 600–700 species of Eucalyptus and its close allies support large numbers of moth species, together with substantial radiations of other plant-feeding insects such as Homoptera, Coleoptera and others but, whereas many butterflies occur in forest and woodland environments, they almost all depend on other plants for larval foods.