gongylodes

Gongylodes are specialized nutrient bodies produced by the fungal cultivar Leucoagaricus gongylophorus, which leaf-cutting ants cultivate in their nests. In some scientific texts the term gongylodes (plural) is used interchangeably with gongylidia to refer to these bulbous hyphal swellings that function as food for the ants.

In the mutualism between the ants and their fungus, the workers harvest gongylodes from the fungal garden and feed on them; the fungus uses the plant substrate brought by the ants to grow and form gongylodes. Gongylodes are rich in lipids and carbohydrates and provide essential nutrients for all castes of the colony; healthy gongylode production is correlated with stable garden conditions and the proper balance of plant substrate and microbial associates.

Gongylodes originate at the tips or swollen regions of hyphae within the garden. They can appear as bulbous, elongated structures embedded in the hyphal network. Under certain environmental conditions and nutrient status, the fungus allocates carbon and other resources to form gongylodes, which are a key feature distinguishing the cultivated fungus from its free-living relatives.

The fungal cultivar is Leucoagaricus gongylophorus, within the family Agaricaceae; leaf-cutting ants of the tribe Attini, notably Atta and Acromyrmex, maintain extensive fungus gardens that rely on gongylodes as a main energy source. Studying gongylodes helps researchers understand coevolution, nutrient exchange, and domestication in insect–fungus mutualisms.