Megalomyrmex gnomus

Nothing is known about the biology of .

Identification
Brandão (1990) - M. gnomus can be easily distinguished from all other species in the Pusillus group by the sharp tooth under the postpetiole, combined with the smooth translucid longitudinal flange under the petiole.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil.

Castes
Known only from the worker caste.

Nomenclature

 * . Megalomyrmex gnomus Kempf, 1970c: 359, figs. 5-8 (w.) BRAZIL (Mato Grosso do Sul).
 * Type-material: holotype worker, 2 paratype workers.
 * Type-locality: holotype Brazil: Mato Grosso do Sul, Corumbá, 18.x.1953 (C.R. Gonçalves); paratypes with same data.
 * Type-depository: MZSP.
 * Status as species: Kempf, 1972a: 139; Brandão, 1990b: 451 (redescription); Bolton, 1995b: 249.
 * Distribution: Brazil.

Worker
Brandão (1990) - Smooth mandibles with dental formula 2+6; clypeus strongly truncate in lateral view with anterior border round without median denticle; palpal formula 3:1; 12 ocular facets at compound eyes largest diameter; frontal suture not impressed; occipital margin not raised; promesonotal suture obsolete at dorsum; metanotal groove deeply impressed and smooth; dorsal face and declivity of propodeum meeting in a gentle angle; epipetiolar carina complete: non-pedunculate petiole with node slope curve and ventral face with anterior denticle leading to a smooth longitudinal flange; transverse postpetiole with laterally produced spiracles and ventral process in a sharp tooth.

Pilosity: long erect or suberect hairs (exceeding maximum diameter of eyes) at body dorsum, smaller oblique hairs on scapes and legs.

Color: bright yellow with darker gaster.

Type Material
Brandão (1990) - Brandão (1990) - Corumba, Mato Grosso do Sui, Brasil (19°01 'S, 57°39'W). Holotype and 2 paratypes at Museu de Zoologia de USP. The paratypes bear a label indicating Cuyaba as the locality, while in the original description all types are said to come from Corumba. The late Dr. Goncalves confirmed that all types came from a nest series taken in Corumba. I added a label to the paratypes saying: “Inform. do coletor. Localidade tipo: Corumba, MS. BrasiL CRG. 18.x.i953. CRF. Brandão. 1984”.

References based on Global Ant Biodiversity Informatics

 * Brandão C. R. F. 1990. Systematic revision of the Neotropical ant genus Megalomyrmex Forel (Hymenoptera: Formicidae: Myrmicinae), with the description of thirteen new species. Arquivos de Zoologia (São Paulo) 31: 411-481
 * Franco W., N. Ladino, J. H. C. Delabie, A. Dejean, J. Orivel, M. Fichaux, S. Groc, M. Leponce, and R. M. Feitosa. 2019. First checklist of the ants (Hymenoptera: Formicidae) of French Guiana. Zootaxa 4674(5): 509-543.
 * Groc S., J. H. C. Delabie, F. Fernandez, F. Petitclerc, B. Corbara, M. Leponce, R. Cereghino, and A. Dejean. 2017. Litter-dwelling ants as bioindicators to gauge the sustainability of small arboreal monocultures embedded in the Amazonian rainforest. Ecological Indicators 82: 43-49.
 * Kempf W. W. 1970. Taxonomic notes on ants of the genus Megalomyrmex Forel, with the description of new species (Hymenoptera, Formicidae). Studia Entomologica 13: 353-364.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Ulyssea M. A., C. R. F. Brandao. 2013. Catalogue of Dacetini and Solenopsidini ant type specimens (Hymenoptera, Formicidae, Myrmicinae) deposited in the Museu de Zoologia da Universidade de Sao Paulo, Brazil. Papies Avulsos de Zoologia 53(14): 187-209.