Brachymyrmex coactus valid Brazil (Santa Catarina). Neotropic.
Mayr, G. 1887. Südamerikanische Formiciden. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien 37:511-632.   127201

Brachymyrmex coactus degener obsolete combination Brazil (Mato Grosso). Neotropic.
Emery, C. 1906c ("1905"). Studi sulle formiche della fauna Neotropica. XXXVII. Bullettino della Società Entomologica Italiana 37 (1905):107-194.   124672

Brachymyrmex coactus nictitans synonym of Brachymyrmex coactus Costa Rica. Neotropic.
Emery, C. 1906c ("1905"). Studi sulle formiche della fauna Neotropica. XXXVII. Bullettino della Società Entomologica Italiana 37 (1905):107-194.   124672

Brachymyrmex coactus robustus synonym of Brachymyrmex coactus Brazil (Santa Catarina). Neotropic.
Santschi, F. 1923c. Solenopsis et autres fourmis néotropicales. Revue Suisse de Zoologie 30:245-273.   128345