Dimorphic midges

I found a midge floating dead on the small Wbx pond today and it turned out to be a rather battered specimen of Bryophaenocladius xanthogyne. This is a terrestrial-breeding species which has a remarkable sexual dimorphism, the male being almost completely black and the female wholly yellow. It is not uncommon here at this time of year and the picture shows a pair I found a few years back.