Surely one of the most charismatic ants to walk the earth:
Most myrmecologists know this charming Australian ant as Nothomyrmecia. But a minority opinion, largely ignored, places it with an earlier genus Prionomyrmex from Baltic amber.
The disagreement hinges on the interpretation of which morphological features are ancestral, and which are derived. DNA sequences are of little help resolving disputes involving fossils.
I know many ant taxonomists read this blog- what do you think?