The discors species-group of the ant genus Iridomyrmex Mayr is defined
for the first time and revised at the species level. The group is com
posed of two species, I. discors Forel and I. obscurior Forel (the lat
ter previously a subspecies of I. discors). The names I. discors aeneo
gaster Wheeler, I. discors occipitalis Forel and I. discors occipitali
s exilior Forel (an unavailable infrasubspecific name) are newly synon
ymised with I. discors. I. discors is distributed broadly across south
ern Australia (excluding Tasmania) and occupies a wide range of habita
ts. I. obscurior is known from only two collections, both relatively m
oist sites in southeastern Australia.