Fungivory or mycophagy is the process of organisms consuming fungi. Many different organisms have been recorded to gain their energy from consuming fungi, including birds, mammals, insects, plants, amoebas, gastropods, nematodes, bacteria and other fungi. Some of these, which only eat fungi, are called fungivores whereas others eat fungi as only part of their diet, being omnivores.
Animals
Mammals
Many mammals eat fungi, but only a few feed exclusively on fungi; most are opportunistic feeders and fungi only make up part of their diet. At least 22 species of primate, including humans, bonobos, colobines, gorillas, lemurs, macaques, mangabeys, marmosets and vervet monkeys are known to feed on fungi. Most of these species spend less than 5% of the time they spend feeding eating fungi, and fungi therefore form only a small part of their diet. Some species spend longer foraging for fungi, and fungi account for a greater part of their diet; buffy-tufted marmosets spend up to 12% of their time consuming sporocarps, Goeldi’s monkeys spend up to 63% of their time doing so and the Yunnan snub-nosed monkey spends up to 95% of its feeding time eating lichens. Fungi are comparatively very rare in tropical rainforests compared to other food sources such as fruit and leaves, and they are also distributed more sparsely and appear unpredictably, making them a challenging source of food for Goeldi’s monkeys.
Fungi are renowned for their poisons to deter animals from feeding on them: even today humans die from eating poisonous fungi. A natural consequence of this is the virtual absence of obligate vertebrate fungivores, with the diprotodont family Potoridae being the major exception. One of the few extant vertebrate fungivores is the northern flying squirrel, but it is believed that in the past there were numerous vertebrate fungivores and that toxin development greatly lessened their number and forced these species to abandon fungi or diversify.
Mollusks
Many terrestrial gastropod mollusks are known to feed on fungi. It is the case in several species of slugs from distinct families. Among them are the Philomycidae (e. g. Philomycus carolinianus and Phylomicus flexuolaris) and Ariolimacidae (Ariolimax californianus), which respectively feed on slime molds (myxomycetes) and mushrooms (basidiomycetes). Species of mushroom producing fungi used as food source by slugs include milk-caps, Lactarius spp., the oyster mushroom, Pleurotus ostreatus and the penny bun, Boletus edulis. Other species pertaining to different genera, such as Agaricus, Pleurocybella and Russula, are also eaten by slugs. Slime molds used as food source by slugs include Stemonitis axifera and Symphytocarpus flaccidus. Some slugs are selective towards certain parts or developmental stages of the fungi they eat, though this behavior varies greatly. Depending on the species and other factors, slugs eat only fungi at specific stages of development. Moreover, in other cases, whole mushrooms can be eaten, without any trace of selectivity.
Insects
In 2008, Euprenolepis procera a species of ant from the rainforests of South East Asia was found to harvest mushrooms from the rainforest. Witte & Maschwitz found that their diet consisted almost entirely of mushrooms, representing a previously undiscovered feeding strategy in ants. Several beetle families, including the Erotylidae, Endomychidae, and certain Tenebrionidae also are specialists on fungi, though they may eat other foods occasionally. Other insects, like fungus gnats and scuttle flies, utilize fungi at their larval stage. Feeding on fungi is crucial for dead wood eaters as this is the only way to acquire nutrients not available in nutritionally scarce dead wood.
Birds
Jays (Perisoreus) are believed to be the first birds in which mycophagy was recorded. Canada jays (P. canadensis), Siberian jays (P. infaustus) and Oregon jays (P. obscurus) have all been recorded to eat mushrooms, with the stomachs of Siberian jays containing mostly fungi in the early winter. The ascomycete, Phaeangium lefebvrei found in north Africa and the Middle East is eaten by migrating birds in winter and early spring, mainly by species of lark (Alaudidae). Bedouin hunters have been reported to use P. lefebvrei as bait in traps to attract birds. The ground-foraging superb lyrebird Menura novaehollandiae has also been found to opportunistically forage on fungi.