Ryukyu Flycatcher males often sing from deep inside the undergrowth, making them difficult to photograph, but this one had come out to a branch at the forest edge to sing. ^^

The differences from the mainland Narcissus Flycatcher are the call, the colour of the throat and breast, and the back colour. The mainland bird's call is complex, while the Ryukyu Flycatcher's is a simple "fee-fee." The Ryukyu Flycatcher also lacks the orange on the throat seen in the Narcissus Flycatcher — from the throat down to the vent it is a vivid yellow throughout. And while the mainland Narcissus Flycatcher has a black back, the Ryukyu Flycatcher's is an olive-tinged black, somewhat duller.

Singing its heart out. You can see the olive-tinged black of the back.