Alien and cryptogenic fungi and oomycetes in Austria: an annotated checklist (2nd edition)

Fungal invasions can have far-reaching consequences, and despite increasing relevance, fungi are notoriously underrepresented in invasion science. Here, we present the second annotated checklist for alien and cryptogenic fungi and oomycetes in Austria. This list contains 375 taxa of which 278 are classified as established; compared to the first checklist from 2002, this amounts to an almost five-fold increase and the number of decade-wise first records is steadily rising since the mid-twentieth century. The introduction pathway is unclear for the vast majority of taxa, while the main means of spread within the country is unassisted secondary spread. Fungi were predominantly introduced from the Northern Hemisphere, especially North America and Temperate Asia. Rates of newly recorded alien fungi differ among phyla; the majority belongs to the Ascomycota, which experienced an 9.6-fold increase in numbers. Orders found most frequently are powdery mildews (Erysiphales, Ascomycota), downy mildews (Peronosporales, Oomycota), agarics (Agaricales, Basidiomycota), Mycosphaerellales (Ascomycota), rusts (Pucciniales, Basidiomycota) and Pleosporales (Ascomycota). The majority (about 80%) of the taxa are plant pathogens, while animal pathogens are few but severely affecting their native hosts. The dominance of pathogens in our checklist underlines the need of better tackling fungal invasions—especially in the light of emerging infectious diseases—and highlights potential knowledge gaps for ectomycorrhizal and saprobic alien fungi, whose invasion processes are often much more inconspicuous. Our results show that fungal invasions are a phenomenon of increasing importance, and collaborative efforts are needed for advancing the knowledge and management of this important group.