Fungus growing ants

De Souza et al. (2007) - The fungus-growing ants are a New World group of > 200 species, all obligate symbionts with a fungus they use for food. The These ants are found across the American continents and the West Indies and comprise at present > 200 described species. Two genera, Atta and Acromyrmex, are called leaf-cutting ants because most species culture their fungus on freshly cut foliage and flowers (Müeller et al., 2001). This particular foraging behavior makes these ants major agricultural pests.

See this chapter of The Ants for a general overview of these intriguing ants.

Social Parasitism
De Souza et al. (2007) - Social parasitism, the exploitation of the nest of another species without contributing to colony maintenance, for example the cultivation of a fungus garden, has been reported occasionally in the attine ants. Megalomyrmex species can coexist as social parasites in attine colonies, consuming the fungus garden (Brandão, 1990; Adams et al., 2000). Gnamptogenys hartmani is also a specialized agro-predator of Trachymyrmex and Sericomyrmex fungus-growing ants in Panama (Dijkstra & Boomsma, 2003). Five taxa are known to be social parasites of other Acromyrmex species, living in and feeding on their fungus gardens, but not contributing to its maintenance: Pseudoatta argentina and Pseudoatta argentina platensis (parasites of Acromyrmex lundii, Acromyrmex heyeri and possibly Acromyrmex balzani), and Pseudoatta sp. (a parasite of Acromyrmex rugosus) produce no worker caste (Santschi, 1926; Bruch, 1928; Gallardo, 1929; Delabie et al., 1993). Rabeling and Bacci (2010) have discovered a workerless inquiline species Mycocepurus castrator that parasitizes Mycocepurus goeldii. In contrast, the recently discovered Acromyrmex insinuator (a parasite of Acromyrmex echinatior) does produce workers (Schultz et al., 1998). Sumner et al. (2004) found that Pseudoatta sp. was not closely related to its host, but A. insinuator was closely related to its host, A. echinatior. Acromyrmex ameliae, a social parasite of Acromyrmex subterraneus and Acromyrmex subterraneus brunneus in Minas Gerais, Brasil. Like A. insinuator, it produces workers and appears to be closely related to its hosts.

Genera

 * Acromyrmex
 * Apterostigma
 * Atta
 * Cyatta
 * Cyphomyrmex
 * Kalathomyrmex
 * Mycetagroicus
 * Mycetarotes
 * Mycetophylax
 * Mycetosoritis
 * Mycocepurus
 * Myrmicocrypta
 * Paramycetophylax
 * Sericomyrmex 
 * Trachymyrmex