Citizen science reveals the Palearctic poison hemlock moth Agonopterix alstroemeriana (Clerck) (Lepidoptera: Depressariidae) has established in Australia

We report the first occurrence in Australia of the poison hemlock mothAgonopterix alstroemeriana(Clerck), a monophage on the environmental weedConium maculatumL. (Apiaceae). The hostplant, also of European origin, is a familiar toxic weed in southern Australia and the moth may have some potential as a biocontrol agent. It joins a list of other Palaearctic species undergoing range expansion into the southern temperate zone and probably colonised Tasmania via New Zealand where it first established in 1986. The discovery was facilitated by a citizen science application for smart-phones linking images of fauna and flora taken in the field to crowd-sourced identification resources, which can quickly converge to a satisfactory determination. In addition to its potential utility in the control of poison hemlock, the reunion of this host and its defoliating monophage after almost 150 years offers a testbed for theories of insect-hostplant evolution.