The Ezo rintou is a native of the northern island of Hokkaido, Japan. It is a lovely deep blue gentian flower.
Gentians or rintou (in Japanese) are very popular flowers. There are between 700 and over a thousand species (depending on which website you visit) with around 400 species from China alone (more than half of those are endemic). The potted plants are sold very cheap, with the prices going higher for the deepest shades of blue which are the Yezo-rintou from northern island of Hokkaido. I was shown this unusual blue and white gentian by my florist.