Calopteryx coomani (Fraser, 1935)

This species was described by R. Martin in 1904 base on the specimens collected from Tonkin, Vietnam.

A large size damselfly, it is shining metallic green with two pairs of dark colour wings. The head, thorax and abdomen are green metallic, the legs are delegate and spiny, the middle and hind tibia are curve. The wings are dark, the colour is same in both sides, the wings are not unicolour, and remarkably there is a large basal anal patch hyaline in forewings. The forewings of females have a white spot at pterostigma position and it is called psedopterostigma.

They are live at clean streams in pristine forests on high limestone mountains of North Vietnam. The mature forms fly during the rain season and they live in shade area with high humidity. Occasionally, males perch in the sunlight with the wings folded along the abdomen and show their shining metallic green body. They are not so active and usually fly weakly among branches of vegetations near the breeding sites. 

Male, Tam Dao National Parck, photographed by Cuong Do

Female with the white spot on her wings, Tam Dao National Park, photographed by Cuong Do