Iris setosa is a species in the genus Iris, it is also in the subgenus of Limniris and in the Iris series Tripetalae. It is a rhizomatous perennial from a wide range across the Arctic sea, including Alaska, Maine, Canada (including British Columbia, Newfoundland, Quebec and Yukon), Russia (including Siberia), northeastern Asia, China, Korea and southwards to Japan. It has tall branching stems, mid green leaves and violet, purple-blue, violet-blue, blue, to lavender flowers. There are also pink and white forms. It is one of the three Iris species in the Iris flower data set outlined by Ronald Fisher in his 1936 paper "The use of multiple measurements in taxonomic problems" as an example of linear discriminant analysis.