Attini

Classification

Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Order: Hymenoptera
Superfamily: Formicoidea
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini

Pronunciation

How to pronounce Attini: /əˈtiːnaɪ/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Atta mexicana casent0421377 head 1 by wikipedia. Used under a CC BY 4.0 license.

Atta texana casent0006046 dorsal 1 by wikipedia. Used under a CC BY 4.0 license.

Atta mexicana casent0421379 head 1 by April Nobile. Used under a CC BY 4.0 license.

Atta mexicana casent0421377 dorsal 1 by wikipedia. Used under a CC BY 4.0 license.

Leucoagaricus gongylophorus grown by Atta texana (Texas, USA) 2 by Blake Bringhurst. Used under a CC BY 4.0 license.

Acromyrmex versicolor casent0104036 dorsal 1 by April Nobile. Used under a CC BY 4.0 license.

Summary

The Attini tribe includes all fungus-growing ants, known for their unique farming habits that significantly impact the ecosystem. They engage in an ant-fungus mutualism, growing fungi from plant materials and serving as important ecological agents in their habitats.

Habitat

Fungus-growing ants are primarily found in the Western Hemisphere. Lower attines live in inconspicuous nests with 100–1000 individuals, while higher attines exist in colonies of 5–10 million ants in large subterranean nests with interconnected fungus-bearing chambers.

Distribution

Found throughout the Western Hemisphere, with species ranging from the pine barrens in New Jersey, USA, to the cold deserts in Argentina.

Diet

Attini ants cultivate fungi from the family Agaricaceae, mainly from the genera Leucoagaricus and Leucocoprinus. They primarily feed on the fungal staphylae, which are rich in carbohydrates and lipids.

Life Cycle

The lifecycle begins when a queen lays eggs in a newly dug chamber, creating a fungus garden within a few days. Colonies take several years to establish fully, with growth rates accelerating after two years.

Reproduction

Typically, one queen resides in a colony, which casts off her wings after a mating flight and begins the colony's growth. Mating occurs with multiple males for some species, and sperm can remain viable for years in the queen's spermatheca.

Predators

Many species of ants, including Megalomyrmex, may invade and steal from Attini colonies, posing a threat to their fungus gardens.

Ecosystem Role

Fungus-growing ants play a crucial role in their ecosystem, influencing soil composition and the growth of plant life via their leaf-cutting habits, which can defoliate large areas of vegetation.

Health Concerns

Attine gut microbiota is less diverse, putting them at higher risk for diseases that affect their fungus gardens, which are critical for larval development.

Evolution

Attini ants likely evolved from predatory ancestors, transitioning to fungus farming about 55-60 million years ago. Higher attines have developed complex agriculture methods and have co-evolved with their fungal cultivars, which they can no longer survive without.