Osbornellus auronitens (Hemiptera: Cicadellidae: Deltocephalinae), an introduced species new for the Palaearctic region.
The introduction of invasive species may result in important ecological, environmental, and economic impacts. Extensive study of Auchenorrhyncha (Hemiptera) fauna in a wine-growing region in southern Switzerland revealed, for the first time, presence of the Nearctic leafhopper Osbornellus auronitens (Provancher) (Hemiptera: Cicadellidae) in the vicinity of Stabio (Canton of Ticino). The species identity of the collected specimens was confirmed using morphological and molecular characters. All specimens of O. auronitens were collected in a forest of Castanea sativa Miller (Fagaceae), Corylus avellana Linnaeus (Betulaceae), and Alnus glutinosa (Linnaeus) Gaertner (Betulaceae) intermixed with Cornus sanguinea Linnaeus (Cornaceae), Salix Linnaeus (Salicaceae), and Rubus Linnaeus (Rosaceae). In its native range this leafhopper is polyphagous and a relatively common visitor in vineyards. Based on analysis of the barcoding region of the mitochondrial cytochrome oxidase subunit I gene of the collected O. auronitens, 100% identity with specimens of the same species originating from Canada was determined. Osbornellus auronitens is morphologically similar to Scaphoideus titanus Ball (Hemiptera: Cicadellidae), another introduced Nearctic leafhopper, which was involved in severe outbreaks of disease caused by the Grapevine flavescence dorée phytoplasma (Bacteria: Acholeplasmataceae) in European viticultural regions since the 1960s. In this paper, we report the morphological features to distinguish O. auronitens from S. titanus, and discuss the possible implications of its expected spread across the Old World.