The word "born" is being used here with poetic licence, as dragonflies are not born in any literal sense of the word. In the course of their life cycle they go through incomplete metamorphosis, and don't be mislead by that word "incomplete". The metamorphosis is incomplete only insofar as odonates don't pass through a pupal stage, but otherwise the change is very complete indeed, and when one compares the naiad to the adult dragonfly it's hard to believe they are formed from the same DNA.
This is a Dragonhunter, Hagenius brevistylus, and with a length of 75 mm to 90 mm it's one of our larger dragonflies. As its name suggests in addition to large butterflies and moths Dragonhunters prey on other dragonflies. A picture is worth a thousand words, here's the story of a dragonfly's journey to adulthood, with the first signs of emergence occuring shortly before 11:40 AM ...
"The internal tracheal system is 'closed', which means that the spiracles (openings to the outside) are sealed in the nymph, but must obviously open at the time of the adult moult. The tracheal system extends throughout the body and in the adult opens to to outside through spiracles in the thorax and the abdomen. In the adult the thoracic trachea are very well developed because of the very high oxygen requirements of the flight musculature and hence the evidence of them in the exuviae is particularly obvious. How or if the naiads shed the lining of these tubes in their aquatic moults is a mystery to me. Perhaps the spiracles open at that time to allow moulting.
The internal tracheae serve as the transportation system throughout the body for the oxygen picked up from the water through the thin cuticle of the gill. (Yes, insect rectums are also lined with cuticle.) I don't know how much of a role in oxygen transport the blood plays, but in most larger insects other than bloodworms it is fairly minor. In damselfly naiads you can see the branches of the tracheal system throughout the external gills, hence the term 'tracheal gills'."
And there we have it. The naiad not only morphs from a wingless underwater crawler to one of the most superlative fliers in the natural world, and somehow that amazing prementum which shoots the jaw out to grab passing prey turns into the much different (but just as deadly, from an insect's point of view) jaw structure of an adult, but the insect's entire breathing system changes over as well. In a case like this maybe a picture isn't worth a thousand words after all, because it can only convey a pale shadow of what's really going on here ... and so much for the "brief interlude", now back to the show ... 11:47 AM ...
