Male Crimson Marsh Glider or Dropwing (Trithemis aurora)
When I saw photos of this dragonfly previously, I always presumed the photographer had oversaturated the colour for appearance's sake. But they are truly this vibrant and breathtaking.
This posture amongst dragonflies is called obelisking. It may have several functions. It may be for postural thermoregulation whereby the abdomen is raised until its tip points at the sun, minimizing the surface area exposed to solar radiation. There are certain species in certain weather conditions for which this seems standard. It may also be a posture adopted by males to display bright colors or markings while guarding their territories or during conflicts with other males.
Pu'er, Yunnan, China