Neivamyrmex gibbatus

This species is only known from queens and/or workers and has yet to be associated with males.

Identification
Jack Longino: Mesonotum distinctly humped; antennal scape surpasses posterior margin of head.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Colombia, Costa Rica, Ecuador, French Guiana, Guyana, Panama, Suriname, Venezuela.

Biology
Jack Longino: I have collected this species five times, always as nocturnal columns on the ground surface in wet forest habitats. The four Costa Rican collections are from sea level to 500m elevation; a Venezuelan collection was from 1100m. In one of the Costa Rican raiding columns there was ant prey: Tapinoma, Pheidole and Strumigenys smithii.

On the Barva transect in Costa Rica I saw a column that emerged from dense vegetation onto a trail, moved about 5m along the trail and across a log, and disappeared into dense vegetation on the other side. It was a dense swath of ants, perhaps 5-10cm wide, moving rapidly. I watched the continuously flowing column for several minutes, and it was obvious that the colony was very large. At times the trail seemed to scintillate, and when I looked closely I discovered that I was seeing the sparkle of light reflecting from the wings of hundreds of wasps in the Diapriidae. Lubomir Masner later identified these as a species of Acanthopria. Hundreds at a time were within my field of vision, running with the workers.

O'Donnell et al. (2020) report this species foraging only at night.

Nomenclature

 * . Neivamyrmex gibbatus Borgmeier, 1953: 45, fig. 30 (w.q.) COSTA RICA, PANAMA (Barro Colorado I.), GUYANA.
 * Type-material: syntype workers (number not stated), 1 syntype ergatoid queen.
 * Type-locality: Costa Rica: Santa Clara Prov., Hamburgfarm, nos. 5659, 5908 (F. Nevermann), same data but nos. 7, 167, 173, and 178, same data but 31.xii.1937, and 24.i.1938, syntype workers and queen Panama: Canal Zone, Barro Colorado I., i.1948, no. 224 (T.C. Scheirla), Barro Colorado I., 22.xi.1947, no. 131, and 2.xii.1947, no. 134, Guyana (“British Guiana”): Kartabo, 25.vii.1924, no. 1093 (S.C. Crawford), Kartabo, 25.vii.1924 (A.E. Emerson).
 * Type-depositories: MCZC, MZSP, USNM, coll. Schneirla.
 * Status as species: Borgmeier, 1955: 347 (redescription); Kempf, 1968b: 371; Kempf, 1972a: 154; Watkins, 1976: 11 (in key); Bolton, 1995b: 289; Palacio, 1999: 155 (in key).
 * Distribution: Brazil, Costa Rica, Ecuador, Guyana, Panama.

References based on Global Ant Biodiversity Informatics

 * Baccaro F. B., J. L. P. de Souza, E. Franklin. V. Lemes Landeiro, and W. E. Magnusson. 2012. Limited effects of dominant ants on assemblage species richness in three Amazon forests. Ecological Entomology 37: 1-12.
 * Basset Y., L. Cizek, P. Cuenoud, R. K. Didham, F. Guilhaumon, O. Missa, V. Novotny, F. Odegaards, T. Roslin, J. Schmidl et al. 2012. Arthropod diversity in a tropical forest. Science 338(6113): 1481-1484.
 * Borgmeier T. 1953. Vorarbeiten zu einer Revision der neotropischen Wanderameisen. Studia Entomologica 2: 1-51.
 * Borgmeier T. 1955. Die Wanderameisen der neotropischen Region. Studia Entomologica 3: 1-720.
 * Esteves F. A., C. R. F. Brandao, and L. P. Prado. 2011. The type specimens of Dorylomorph ants (Hymenoptera, Formicidae: Aenictinae, Ecitoninae, Cerapachyinae, Leptanilloidinae) deposited in the Museu de Zoologia da Universidade de Sao Paulo, Brazil. Papeis Avulsos de Zoologia 51(22): 341-397.
 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * 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.
 * Kempf W. W. 1968. Miscellaneous studies on Neotropical ants. IV. (Hymenoptera, Formicidae). Studia Entomologica 11: 369-415.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Lattke J. E., M. Kaspari, S. ODonnell, and S. Powell. 2007. Las hormigas ecitoninas de Venezuela (Hymenoptera: Formicidae: Ecitoninae): elenco preliminar. Entomotropica Vol. 22(3): 153-170.