Trachymyrmex septentrionalis valid U.S.A. (New Jersey). Nearctic.
McCook, H. C. 1881a ("1880"). Note on a new northern cutting ant, Atta septentrionalis. Proceedings of the Academy of Natural Sciences of Philadelphia 32:359-363.   127285

Trachymyrmex septentrionalis obscurior synonym of Trachymyrmex septentrionalis U.S.A. (Texas). Nearctic.
Wheeler, W. M. 1907d. The fungus-growing ants of North America. Bulletin of the American Museum of Natural History 23:669-807.   130021

Trachymyrmex septentrionalis obscurior crystallina unavailable U.S.A. (Texas). Nearctic.
Wheeler, W. M. 1911i. Descriptions of some new fungus-growing ants from Texas, with Mr. C. G. Hartman's observations on their habits. Journal of the New York Entomological Society 19:245-255.   130063

Trachymyrmex septentrionalis obscurior irrorata unavailable U.S.A. (Texas). Nearctic.
Wheeler, W. M. 1911i. Descriptions of some new fungus-growing ants from Texas, with Mr. C. G. Hartman's observations on their habits. Journal of the New York Entomological Society 19:245-255.   130063

Trachymyrmex septentrionalis seminole synonym of Trachymyrmex septentrionalis U.S.A. (Florida). Nearctic.
Smith, M. R. 1930a. A list of Florida ants. Florida Entomologist 14:1-6.   128756

Trachymyrmex septentrionalis vertebrata synonym of Trachymyrmex septentrionalis U.S.A. (New Jersey). Nearctic.
Wheeler, W. M. 1911i. Descriptions of some new fungus-growing ants from Texas, with Mr. C. G. Hartman's observations on their habits. Journal of the New York Entomological Society 19:245-255.   130063