San’inshiroganesou, or Dichocarpum
nipponicum var. sarmentosum, is a
perennial occurring in damp places by a mountain river. It resembles
another species in the same genus. Still, the difference is clear
because it provides a dark-purple crest at the base of each petaloid
sepal, which characterizes this species. As for petals, they are the
yellow portions in flowers.
After flower, this species
spreads runners to make new growth.