Wikipedia
Polystachyinae
Polystachyinae is a subtribe within the tribe Vandeae in family Orchidaceae. It consists of 4 genera and about 228 known species. The type genus of this subtribe is Polystachya. The group is pantropical, being native to tropical Africa primarily, but also to tropical America. Members of this group are epiphytic and They are distinguished from the other subtribes in the tribe Vandeae by their sympodial growth habit and the presence of four pollinia. Pollination is mostly by small species of bees, however some species (e.g. Polystachya concrete) exhibit auto-pollination.