Acromyrmex heyeri

Acromyrmex heyeri is common in Rio Grande do Sul, Brazil. They harvest monocotyledonous leaves (Loeck and Grutzmacher 2001) and masticate their collected plant material into tiny pieces to create the substrate for growing their fungal gardens. A molecular study of co-occuring populations of this species and Acromyrmex ambiguus showed both of these species are cultivating Leucoagaricus gongylophorus but that there are differences in the fungal strains used by the two ant species (Pereira et al. 2015). This ant is host to the socially parasitic Pseudoatta argentina in Argentina and Acromyrmex charruanus in Uruguay.

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Brazil, Paraguay, Uruguay.

Biology
Barrera et al. 2015 studied the diversity of leaf cutting ants along a forest-edge-agriculture habitat gradient. Their study site, in Chaco Serrano of Central Argentina, had forest remnants of various sizes within an agriculture area with wheat, soy and maize. A few colonies of A. heyeri and Acromyrmex silvestrii were found along the forest edge. Acromyrmex crassispinus was the most abundant Acromyrmex species sampled (42% of 162 colonies) and was most abundant in the forest interior. Acromyrmex lundii and Acromyrmex striatus were also present, with the former also found in the forest interior. The latter and A. striatus were the most abundant in the forest edge habitat with A. crassispinus present there at a slightly lower density.

Nomenclature

 *  heyeri. Atta (Moellerius) heyeri Forel, 1899c: 31 (footnote) (s.w.) BRAZIL. Emery, 1905c: 43 (q.m.); Bruch, 1921: 199 (q.m.); Goni et al. 1983: 365 (k.). Combination in Acromyrmex: Bruch, 1914: 217; in Acromyrmex (Moellerius): Fowler, 1988: 287. Senior synonym of gaudens, lillensis: Fowler, 1988: 287. See also: Gonçalves, 1961: 127.
 * gaudens. Acromyrmex (Moellerius) heyeri var. gaudens Santschi, 1925e: 164 (w.) ARGENTINA. Junior synonym of heyeri: Fowler, 1988: 287.
 * lillensis. Acromyrmex (Moellerius) heyeri var. lillensis Santschi, 1925e: 165 (w.) ARGENTINA. Junior synonym of heyeri: Fowler, 1988: 287.