Attini

Definition

A tribe of myrmicine ants (Formicidae) comprising all fungus-growing ants that cultivate basidiomycete fungi for food. Members exhibit obligate mutualism with their fungal cultivars, with behavioral and morphological specializations including substrate preparation, fungal inoculation, and antibiotic application to suppress competing molds. The tribe includes both leaf-cutting genera (Atta, Acromyrmex) that harvest fresh vegetation and non-leaf-cutting genera (Apterostigma, Cyphomyrmex, Trachymyrmex) that use insect frass, seeds, or decaying wood.

Etymology

From Atta (type genus) + -ini (tribe suffix)

Example

Atta cephalotes, a member of the Attini, forages for leaf fragments that serve as substrate for their Leucoagaricus gongylophorus fungal gardens.

Synonyms

• fungus-growing ants
• attine ants

Related Terms

• Atta
• Acromyrmex
• ant-fungus mutualism
• gongylidia
• myrmecophyte
• Mycetophylax
• Trachymyrmex
• Pseudoatta

Usage Notes

Sometimes referred to broadly as 'leafcutter ants,' though this properly describes only the two genera Atta and Acromyrmex; many Attini do not cut leaves. The tribe-level classification distinguishes these ants from other myrmicines by their exclusive reliance on fungal cultivation. Formerly treated as a subtribe (Attina) within Myrmicini in older literature. The fungal cultivars are transmitted vertically (colony to offspring) and have coevolved with their ant hosts for approximately 50–60 million years.