tbc - I have it somewhere but if you think you know, feel free to chip in!
Large sterile shield fronds, which embrace their host and form a basket over time to collect detritus to feed the fern. Forked pendulous fertile fronds, which bear spores. First photo is a small tree festooned with them, second shows individual plants on a very tall tree.
Forests. (Chae Son National Park)
Cultivated specimens tied onto telegraph poles etc were a very common sight in villages we passed through in northern Thailand but these were the only naturally occurring plants I saw.