The male Coral-tailed Cloudwing (Tholymis tillarga) is a medium sized dragonfly (body length: 44-47mm).
The male has reddish eyes, yellowish red thorax and coral red abdomen. 
Its wings are transparent but the hindwings have a brown patch near the base.
The male's hindwings have a distinct (cloudy, hence the name) white patch beside the brown patch. 
The female is brown and also has a brown patch in the hindwings but lacks the white patch.
The species has a wide distribution in all parts of the world except Europe and the Americas. 
It is widespread in Africa, Asia, Australia, and Indian Ocean Islands.

1st & 2nd photo: A female. Cat Ba National Park, Cat Ba Island, Vietnam, 7 January 2024
3rd, 4th & 5th photo: A female. Hoi An area, Vietnam, 27 December 2023