I hereby revise, for the second time, the primarily Neotropical solenopsidine ant genus Megalomyrmex, describing M. wettereri n. sp., of the Silvestrii group, based on workers and gynes. Megalomyrmex latreillei Forel is synonymyzed under M. foreli Emery. The gyne of M. poatan is described and that of M. wallacei redescribed; males of M. acauna, M. incisus and M. wallacei are described. New locality records are given for M. ayri, M. cupecuara, M. goeldii, M. iheringi, M. modestus, and M. wallacei (Modestus group); M. acauna, M. balzani, M. cyendyra, M. emeryi, M. foreli, M. glaesarius, M. leoninus, M. staudingeri, and M. timbira (Leoninus group); M. poatan, M. silvestrii, and M. symmetochus (Silvestrii group), and M. drift, M. incisus, M. myops and M. pusillus (Incisus group). New biological data are recorded for M. acauna, M. goeldii, and M. wallacei. Comments are made for M. bidentatus, M. miri and M. mondabora.
Hymenoptera; Formicidae; Myrmicinae; Megalomyrmex; taxonomy; biology
