Japan Flora: Perennial, short appressed-strigillose, stoloniferous; stems 7-20 cm. long, soon decumbent; leaves ovate, 3-5 cm. long, 1.5-2.5 cm. wide, acute, truncate to shallowly cordate or rounded at base, the lower ones long-petiolate; inflorescence soon becoming lateral, un­branched, loosely 3- to 10-flowered, bractless, the pedicels 1-1.5 cm. long, ascending; corolla about 10 mm. across, pale blue, the tube about 2 mm. long; stamens inserted above the middle of the tube, the anthers about 0.5 mm. long. May-June. 

Honshu (centr. and n. distr.); rare.