The females of the two species look very different, especially in brood colouration, so It seems to me that the brood colours are displayed to other adults, and it's actually the fin twitching etc. Maybe it's a language that all apistos understand, regardless of species. Maybe it's a language that all apistos understand, regardless of species. That's interesting observation, Jason. Fin twitching is found in a lot of cichlid species.
Females seem to do it more often than males.
I have a week old swarm of Laetacara sp. Orange fin and the female is twitching like crazy. West African Hemichromis elongatus do it too. Quite recently I noticed my 8 inch female gold Severum fanning Microgeophagus altispinosa spawn. The small altis were almost having a fit when this huge blimp decided to take over for a short while.