First evidence of establishment of the palm borer moth Paysandisia archon (Burmeister, 1879) in southern Switzerland

Abstract

We report the first evidence of establishment of the palm borer moth Paysandisia archon (Burmeister, 1879; Lepidoptera: Castniidae) in southern Switzerland. Originally from South America, P. archon has been increasingly spotted in southern Europe in recent years, where it poses a substantial threat to palms as its larvae bore into their meristem, feeding on the inner tissues, weakening the plants, and, in most cases, leading to their demise. We conducted non-systematic surveys and compiled reports of sightings of P. archon and its attributed damages, which were then all stored in an online database. Sightings and damage caused by P. archon have been confirmed across multiple locations in southern Switzerland, with major infestations reported on the northern shore of the Lago Maggiore and affecting various palm species. While P. archon poses a major threat to cultivated palm specimens that are iconic for the (sub)urban landscape of southern Switzerland, it may also help control the undesired spread of the invasive Chinese windmill palm Trachycarpus fortunei in the peri-urban forests.