Birdwood's Mucuna is a very interesting species. A large climber, with huge, thick, river spanning vines, like slim horizontal tree trunks. Firstly, legend has it that farmers were so annoyed by birds in their fields that Iron-Crutch Li (he is one of the Eight Immortals) used magic to turn the birds into flowers, and hang them along this climbing vine. They were only released during (the very recent) Ching Ming Festival. So I went to look for them on the eve of the festival, as they only flower for a few weeks a year, around this time.
Dark forest means a spot of flash to light these birdlike flowers, with red beaks.
this is the "Rice Bird Flower" in Chinese. Also interesting, i understand that these are pollinated by bats.
Find them in the forests of Tai Mo Shan, or in the valleys above Tai Po.
This one has a bit more flash...