Diplacodes exilis, sometimes also called the Madagascar Percher, is a rather small dragonfly within the family Libellulidae.
Four species in the genus Diplacodes occur in Africa and only Diplacodes exilis is endemic to Madagascar.
The African species are difficult to separate.
As they mature, males and females become black.

Klaas-Douwe Dijkstra, the Dutch leading expert on African dragonflies, helped me identifying this species.

Djamandjary, Nosy Be, Madagascar, 29 February 2020