The head is bluish-black and the skin around eyes is cobaltic. The back and wings are purplish-brown. The under surface is white, but the wings’ and the tale’s are brown. The length of male is 44.5cm and female is 17.5cm. Male has long tail which is purplish-black, the female ‘s is brown. The female’s upper surface is light and tail’s length is shorter than male.
This birds like dense woods of low mountain. They prey on insects by flying among the trees. They nest small among the branchs and lay 3 to 5 eggs. The breeding season is may to july, the period of nesting is 12-days to 14-days, the period of raising is 8-days to 12 days. Both male and female nest and raise young together. The feed is mostly the insect species, sometimes is spider. They grow throughout East Asia, Japan, the western Pacific and winter in Southeast Asia.