Abstract
Proditrix nielseni, sp. nov., a giant of the world yponomeutoid fauna, is described from cool temperate rainforest in montane Tasmania. The distinctive larvae feed in the crown of the endemic 'pandani', Richea pandanifolia, the world's tallest species of Epacridaceae. This is the first record of the genus Proditrix Dugdale from Australia and from a dicotyledonous hostplant. It represents a second austral plutellid genus shared between Tasmania and New Zealand.