Odonata: Hemicorduliidae
Hemicordulia tau
Tau Emerald dragonflies mating.
The dragonflies joined up and were mating in flight before the male found a place to hang on vegetation to complete the process.
The male holds the female around the head whilst she positions her tail to the male's secondary sex organ in order to be fertilised. Secondary because he has transfered sperm there from his primary sex organ at the end of his abdomen (currently at the back of his partners head) in anticipation of this event.
Sex can be complicated.