Identification of females

We all know – at least principally – how to identify male licorice gouramis, at least in their displaying colours.
But how to identify the species by their females? Say which is which by some clear markers?
Of course, there are some species which make the task rather easy because of clear structural markers: paludicola for instance, take the long dorsal fin.
But could we identify some other females e.g. by other structural markers or even by fin-colour? Displaying, most females show some colour in their fins that they do not show within “normal life”. I just saw it yesterday again in my spawning filamentosus. That would be a beginning. Perhaps, somebody has an idea with a further species.
Peter Finke (D)