Parasitic fungi occur in virtually every ecosystem, where they can significantly affect the functions of other organisms. Fungal parasites were probably also widespread in the geologic past. However, evidence of fossil fungi and their ecological roles is relatively rare. Here we demonstrate a spectrum of (putative) parasitic relationships in ancient continental ecosystems, using fossil examples of Chytridiomycota, zygomycetous fungi, Basidiomycota, and Ascomycota, along with several fungal fossils whose affinities remain unknown, from different periods of the Phanerozoic. Although many of the hosts no longer exist, the fungi involved mostly appear morphologically very similar to extant forms.