MacKay, W. P. 1998a. A remarkable new species of Paratrechina (Hymenoptera: Formicidae) from the state of Colima, Mexico. Pan-Pacific Entomologist 74:99-101. PDF

MacKay, W. P. 1998b. A new army ant from southern Texas (Hymenoptera: Formicidae). The Southwestern Naturalist 43:333-335. PDF

Mackay, W. P. 1998c. Dos especies nuevas de hormigas de la tribu Attini de Costa Rica y México: Mycetosoritis vinsoni y Mycocepurus curvispinosus (Hymenoptera: Formicidae). Revista de Biología Tropical 46:421-426. PDF

Mackay, W. P. 2000. A review of the New World ants of the subgenus Myrafant, (genus Leptothorax) (Hymenoptera: Formicidae). Sociobiology 36:265-444. PDF

Mackay, W. P. 2003. Adelomyrmex laevigatus Mackay sp. n. Pp. 8-9 in: Fernández, F.; Mackay, W. P. 2003. The myrmicine ants of the Adelomyrmex laevigatus species complex (Hymenoptera: Formicidae). Sociobiology 41:593-604. PDF

MacKay, W. P. 2003. Subfamilia Cerapachyinae. Pp. 277-280 in: Fernández, F. (ed.) 2003. Introducción a las hormigas de la región Neotropical. Bogotá: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, xxvi + 424 pp.

Mackay, W. P. 2004. A new species of the ant genus Acanthostichus Mayr (Hymenoptera: Formicidae) from Paraguay, and a description of the gyne of A. brevicornis Emery. Proceedings of the Entomological Society of Washington 106:97-101. PDF

MacKay, W. P.; Anderson, R. S. 1992 ("1991"). New distributional records for the ant genus Ponera (Hymenoptera: Formicidae) in North America. Journal of the New York Entomological Society 99:696-699. PDF

MacKay, W. P.; Anderson, R. S. 1993. New distributional records for the ant genus Smithistruma (Hymenoptera: Formicidae) in southern United States. The Southwestern Naturalist 38:388-389. PDF

MacKay, W. P.; Baena, M. L. 1993. A new "horned" fungus growing ant, Cyphomyrmex castagnei, from Colombia. Sociobiology 23:31-37. PDF

Mackay, W. P.; Barriga, P. A. 2013. A new species of Neotropical carpenter ant in the genus Camponotus (Hymenoptera: Formicidae), apparently without major workers. Psyche 2012 (4) Article ID 382938:5 pp. 10.1155/2012/382938 PDF

Notes: The online version of this paper does not meet ICZN requirements of availability, but a hard copy of Psyche, Volume 2012, Part 4, in which this article appears, was received at the Canadian Agriculture Library, Ottawa on 14 May 2013. Hence year of publication appears to be 2013.

Mackay, W. P.; Buschinger, A. 2002. A new species of the ant genus Leptothorax (subgenus Myrafant) from Alberta, Canada. Sociobiology 40:539-545.

MacKay, W. P.; Cover, S. P.; Heinze, J.; Hölldobler, B. 1995. Range extensions for the ant Leptothorax pergandei (Hymenoptera: Formicidae): a mesic forest species discovered in the Chihuahuan Desert. Proceedings of the Entomological Society of Washington 97:888. PDF

Mackay, W. P.; Dash, S. T. 2016. A revision of the phalangium species complex of the ant genus Aphaenogaster (Hymenoptera: Formicidae: Myrmicinae). Transactions of the American Entomological Society 142:1-22. 10.3157/061.142.0108 PDF

Mackay, W. P.; Delsinne, T. 2009. A new species of carpenter ant (Hymenoptera: Formicidae: Camponotus) from Paraguay with a key to the New World members of the maculatus species complex. Sociobiology 53:487-498. PDF

MacKay, W. P.; Elias, S. A. 1993 ("1992"). Late Quaternary ant fossils from packrat middens (Hymenoptera: Formicidae): implications for climatic change in the Chihuahuan desert. Psyche (Cambridge) 99:169-184. PDF

MacKay, W. P.; Fagerlund, R. 1997. Range expansion of the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), into New Mexico and extreme western Texas. Proceedings of the Entomological Society of Washington 99:757-758. PDF

Mackay, W. P.; López-Castro, C.; Fernández, F. 2002. A new, high altitude Colombian species of the ant genus Camponotus with dimorphic males and females (Hymenoptera: Formicidae). Sociobiology 40:421-430. PDF

MacKay, W. P.; Lowrie, D.; Fisher, A.; MacKay, E. E.; Barnes, F. 1988. The ants of Los Alamos County, New Mexico (Hymenoptera: Formicidae). Pp. 79-131 in: Trager, J. C. (ed.) 1988. Advances in myrmecology. Leiden: E. J. Brill, xxvii + 551 pp. PDF

Mackay, W. P.; MacKay, E. 2008a. [Untitled. New species of Gnamptogenys attributed to Mackay and Mackay.]. Pp. 78, 80-81 and 84-85 in: Lattke, J. E.; Fernández, F.; Arias-Penna, T. M.; Palacio, E. E.; MacKay, W.; MacKay, E. 2008. Género Gnamptogenys Roger. Pp. 66-100 in: Jiménez, E.; Fernández, F.; Arias, T.M.; Lozano-Zambrano, F. H. (eds.) 2008. Sistemática, biogeografía y conservación de las hormigas cazadoras de Colombia. Bogotá: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, xiv + 609 pp. PDF

Mackay, W. P.; Mackay, E. 2008b. Revision of the ants of the genus Simopelta Mann. Pp. 285-328 in: Jiménez, E.; Fernández, F.; Arias, T.M.; Lozano-Zambrano, F. H. (eds.) 2008. Sistemática, biogeografía y conservación de las hormigas cazadoras de Colombia. Bogotá: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, xiv + 609 pp. PDF

MacKay, W. P.; MacKay, E. 2010. The systematics and biology of the New World ants of the genus Pachycondyla (Hymenoptera: Formicidae). Lewiston, New York: Edwin Mellen Press, xii + 642 pp. PDF

MacKay, W. P.; MacKay, E. E. 1988 ("1986"). Las hormigas de Colombia: arrieras del género Atta (Hymenoptera: Formicidae). Revista Colombiana de Entomología 12(1):23-30. PDF

MacKay, W. P.; MacKay, E. E. 1994. Lasius xerophilus (Hymenoptera: Formicidae), a new ant species from White Sands National Monument, New Mexico. Psyche (Cambridge) 101:37-43. PDF

Mackay, W. P.; MacKay, E. E. 1997a. Una nueva especie de hormiga del género Trachymyrmex (Hymenoptera: Formicidae) del Estado de Chihuahua, México. Sociobiology 30:43-49. PDF

Mackay, W. P.; MacKay, E. E. 1997b. A revision of the Neotropical ants of the montivagus species complex, genus Camponotus, subgenus Myrmentoma (Hymenoptera: Formicidae). Sociobiology 30:319-334. PDF

Mackay, W. P.; MacKay, E. E. 2004. A new species of the ant genus Leptogenys (Hymenoptera: Formicidae) with inflated mandibles. Sociobiology 43:255-258.

MacKay, W. P.; MacKay, E. E. 2006. A new species of the ant genus Pachycondyla F. Smith, 1858 from Ecuador (Hymenoptera: Formicidae). Myrmecologische Nachrichten 8:49-51. PDF

Mackay, W. P.; MacKay, E. E. 2018. Revision of the New World cork-headed ants of the genus Colobopsis. Mauritius: LAP LAMBERT Academic Publishing, 279 pp. PDF

Mackay, W. P.; MacKay, E. E. 2019. Género Camponotus. Capítulo 26. Pp. 743-789 in: Fernández, F.; Guerrero, R. J.; Delsinne, T. (eds.) 2019d. Hormigas de Colombia. Bogotá: Universidad Nacional de Colombia, 1198 pp. PDF