4. Diversity of hyperparasitic fungi
Hyperparasitic fungi are found across the fungal tree of life (Fig. 4),
from Cryptomycota to former ‘zygomycetes’ to Basidiomycota (Gleason et al., 2012; Jeffries, 1985; Lutz et al., 2004) (Fig. 5).
The genus Trichoderma (Sordariomycetes: Hypocreales) includes the
best studied mycoparasites, some of which are hyperparasites of plant
pathogens (Brotman et al., 2010; Elad et al., 1980).
Hypocreales is an order with 320 genera that are rich in hyperparasites
of fungi parasitic on plants, animals, and other fungi (Sung et
al., 2007; Wijayawardene et al., 2022) (Fig. 6). Akanthomyces lecanii is a member of this order that exploits
hosts in two different kingdoms: the coffee rust fungus, Hemileia
vastatrix (Pucciniomycetes: Pucciniales), and the coffee scale insect, Coccus viridis (Vandermeer et al., 2009). Having hosts
that themselves are obligate associates with coffee plants as parasites,
potentially enables this dynamic hyperparasite to maintain various
reservoirs for dispersal through time and physical space in the
environment (Jackson et al., 2016). Many other prominent and
well-studied groups of hyperparasites are representatives of
Dothideomycetes. Some examples of hyperparasites in Dothideomycetes are Ampelomyces spp. (Pleosporales) on powdery mildews (Kiss et
al., 2004) and Cladosporium spp. (Capnodiales) on various
parasitic hosts (Moricca et al., 2005).