Fungal and fungal-like pathogens are responsible for some of the most severe diseases occurring in wildlife. During the last decades, natural populations of endangered animal species have experienced an increasing number of fungal infections. Some of the pathogens responsible for these diseases are associated with the fi rst documented extinction events in various species caused by infection and resulting in increasing rates of biodiversity loss (Fisher et al. 2012). Probably, one of the most notorious cases is the so-called ‘crayfi sh plague’ caused by the fungal-like organism Aphanomyces astaci Schikora (Oomycetes). This pathogen is considered among the one hundred world’s worst invasive species (http://www.issg.org), and has destroyed the majority of the native populations of freshwater crayfi sh in Europe (Unestam 1972, Edgerton et al.