The general term “fungicolous fungus” refers to a fungus that is
consistently associated with other fungi (Fig. 2; Gams et al.,
2004; Hawksworth, 1981; Sun et al., 2019). Researchers may also
refer to fungi as fungicolous when the exact nature of the trophic
relationship is not known (Barnett, 1963; Barnett and Binder, 1973). A
distinction between hyperparasites, mycoparasites, and fungicolous fungi
is made in the literature for several reasons. First, hyperparasitic
fungi are frequently studied for their potential use in biocontrol of
economically important parasites and pathogens (Brotman et al.,
2010). Second, they represent an opportunity to study trophic cascades
and natural dynamics of predation in both host and parasite populations
(Fig. 3; Parratt and Laine, 2016). Finally, parasitism of another
organism that is strongly or obligately reliant on a specific host, has
potential impacts on the dispersal and evolution of that organism, which
parasites of non-pathogens may not experience.