''Cypripedium acaule'' is a member of the orchid genus ''Cypripedium''. Members of this genus are commonly referred to as lady's slipper orchids. First described in 1789 by Scottish botanist William Aiton, ''C. acaule'' is commonly referred to as the pink lady's slipper, stemless lady's-slipper, or moccasin flower. The pink lady's slipper is the provincial flower of Prince Edward Island, Canada and the state wildflower of New Hampshire, United States.