It's rare because it proved impossible to raise in cultured environments, and so it is rarely sold in regular collections, and costs a small fortune if you find it. It has no stem, and the leaves are degenerate. The roots absorb moisture and chlorophyll. Every plant has about 10 flowers, and they bloom one after the other during the summer (June to August).
If you see one make sure you don't touch it, as they are considered endangered and it is illegal to puck them.