Geranium thunbergii
Geranium thunbergii is a List of [cranesbill species|cranesbill species] that is commonly known as Japanese geranium or Japanese cranesbill. It is one of the most popular folk medicines and also an official antidiarrheic drug in Japan. It is called ゲンノショウコ.
Geraniin is an ellagitannin found in G. thunbergii.