... competing with wing loss in flies (flightlessness), at 25 events counted to date. Can't find an up to date citation; a neat phylogenetic tree of #Diptera marking all the apomorphic events was shown to me by Darren Williams. There's Wagner & Liebherr 1992 https://www.sciencedirect.com/science/article/abs/pii/016953479290047F listing 22 insect orders with flightless species: almost all of them have species with secondary wing loss.
