• Wheeler & Wheeler, 1953c: 164 (l.)
• Status as species: Wheeler, 1904f: 305; Wheeler, 1904i: 348; Wheeler, 1905j: 399; Wheeler, 1906g: 16; Wheeler, 1910a: 570; Wheeler, 1913d: 116; Wheeler, 1913i: 477 (redescription); Emery, 1925d: 256; Wesson & Wesson, 1940: 101; Cole, 1943a: 389; Buren, 1944a: 306; Creighton, 1950a: 500; Smith, 1951c: 862; Smith, 1958c: 155; Carter, 1962a: 8 (in list); Kutter, 1968c: 207; Smith, 1979: 1462; Bolton, 1995b: 194; Coovert, 2005: 152; Ellison et al., 2012: 151.
• Senior synonym of Formica difficilis consocians: Cole, 1943a: 389; Creighton, 1950a: 500; Smith, 1951c: 862; Kutter, 1968c: 207; Smith, 1979: 1462; Bolton, 1995b: 194; Coovert, 2005: 152.
• Senior synonym of Formica habrogyna: Cole, 1943a: 389; Creighton, 1950a: 500; Smith, 1951c: 862; Smith, 1979: 1462; Bolton, 1995b: 194; Coovert, 2005: 152.

Junior synonyms

• Formica difficilis consocians Wheeler, 1904
• Formica habrogyna Cole, 1939

Obsolete combinations

• Formica rufa difficilis

Citations

• Bolton, B. 1995b. A new general catalogue of the ants of the world. Cambridge, Mass.: Harvard University Press, 504 pp.
• Buren, W. F. 1944a. A list of Iowa ants. Iowa State College Journal of Science 18:277-312. PDF
• Carter, W. G. 1962a. Ants of the North Carolina Piedmont. Journal of the Elisha Mitchell Scientific Society 78:1-18. PDF
• Cole, A. C., Jr. 1943a ("1942"). Synonyms of Formica difficilis Emery (Hymenoptera: Formicidae). Annals of the Entomological Society of America 35:389. PDF
• Coovert, G. A. 2005. The ants of Ohio. Bulletin of the Ohio Biological Survey (New Series) 15 (2):1-196. PDF
• Creighton, W. S. 1950a. The ants of North America. Bulletin of the Museum of Comparative Zoology 104:1-585. PDF
• Ellison, A. M.; Gotelli, N. J.; Farnsworth, E. J.; Alpert, G. D. 2012. A field guide to the ants of New England. New Haven: Yale University Press, xv + 398 pp.
• Emery, C. 1893k. Beiträge zur Kenntniss der nordamerikanischen Ameisenfauna. Zoologische Jahrbücher. Abteilung für Systematik, Geographie und Biologie der Tiere 7:633-682. PDF
• Emery, C. 1925d. Hymenoptera. Fam. Formicidae. Subfam. Formicinae. Genera Insectorum 183:1-302. PDF
• Kutter, H. 1968c ("1967"). Liste sozialparasitischer Ameisen. Archives. Institut Grand-Ducal de Luxembourg (n.s.)33:201-210.
• Smith, D. R. 1979. Superfamily Formicoidea. Pp. 1323-1467 in: Krombein, K. V.; Hurd, P. D.; Smith, D. R.; Burks, B. D. (eds.) 1979. Catalog of Hymenoptera in America north of Mexico. Volume 2. Apocrita (Aculeata). Washington, D.C.: Smithsonian Institution Press, pp. i-xvi, 1199-2209.
• Smith, M. R. 1951c. Family Formicidae. Pp. 778-875 in: Muesebeck, C. F. W.; Krombein, K. V.; Townes, H. K. (eds.) 1951. Hymenoptera of America north of Mexico. Synoptic catalogue. United States Department of Agriculture. Agriculture Monograph 2:1-1420. PDF
• Smith, M. R. 1958c. Family Formicidae. Pp. 108-162 in: Krombein, K. V. (ed.) 1958. Hymenoptera of America north of Mexico. Synoptic catalogue. First supplement. United States Department of Agriculture. Agriculture Monograph 2(suppl. 1):1-305. PDF
• Wesson, L. G.; Wesson, R. G. 1940. A collection of ants from southcentral Ohio. American Midland Naturalist 24:89-103. PDF
• Wheeler, G. C.; Wheeler, J. 1953c. The ant larvae of the subfamily Formicinae. Annals of the Entomological Society of America 46:126-171. PDF
• Wheeler, W. M. 1904f. The ants of North Carolina. Bulletin of the American Museum of Natural History 20:299-306. PDF
• Wheeler, W. M. 1904i. A new type of social parasitism among ants. Bulletin of the American Museum of Natural History 20:347-375. PDF
• Wheeler, W. M. 1905j. An annotated list of the ants of New Jersey. Bulletin of the American Museum of Natural History 21:371-403. PDF
• Wheeler, W. M. 1906g. Fauna of New England. 7. List of the Formicidae. Occasional Papers of the Boston Society of Natural History 7:1-24. PDF
• Wheeler, W. M. 1910a. Ants: their structure, development and behavior. New York: Columbia University Press, xxv + 663 pp. PDF
• Wheeler, W. M. 1913d. Ants collected in Georgia by Dr. J. C. Bradley and Mr. W. T. Davis. Psyche (Cambridge) 20:112-117. PDF
• Wheeler, W. M. 1913i. A revision of the ants of the genus Formica (Linné) Mayr. Bulletin of the Museum of Comparative Zoology 53:379-565. PDF