The male purple emperors of El Salvador are by far more often seen than the females.  The females of this species in particular are very rarely seen.  The reason was discovered several years ago, when it was found to be an inhabitant of canopy flowers, which are normally very small white or creamish – i.e. very wind resistant – and develope in clumps or close proximity, which allows butterflies to walk from flower to flower rather than fly.  After more than 30 years of only seeing 2 damaged females, 5 perfect specimens were seen simultaneously from a rope web that had been set up in a medium height tree!