The new species replaces Platystele jungermannioides as the world’s smallest orchid flower.
The find was made by botanist Lou Jost while inspecting a plant collection in the mountainous region of Ecuador.
It is from the Platystele genus and has petals so thin they are transparent and just one cell thick.
The accidental find took place on the Cerro Candelaria reserve in the eastern Andes, which was created by Ecuador’s EcoMinga Foundation in partnership with the World Land Trust in Britain.
Dr Jost, from the EcoMinga Foundation, is one of the world’s leading orchid hunters.
He said: "It’s a very exciting feeling to find a new species. People think that everything has been discovered but there’s much more to be discovered."