''Asarum asperum'' is a species of flowering plant in the pipevine family,

Aristolochiaceae The Aristolochiaceae () are a family, the birthwort family, of flowering plants with seven genera and about 400 known species belonging to the order Piperales. The type genus is '' Aristolochia'' L. Description They are mostly perennial, ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to Japan, where it is found on

Shikoku is the smallest of the four main islands of Japan. It is long and between wide. It has a population of 3.8 million (, 3.1%). It is south of Honshu and northeast of Kyushu. Shikoku's ancient names include ''Iyo-no-futana-shima'' (), ...

and in the western regions of

Honshu , historically called , is the largest and most populous island of Japan. It is located south of Hokkaidō across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyūshū across the Kanmon Straits. The island ...

. It is particularly common in the vicinity of

Kyoto Kyoto (; Japanese: , ''Kyōto'' ), officially , is the capital city of Kyoto Prefecture in Japan. Located in the Kansai region on the island of Honshu, Kyoto forms a part of the Keihanshin metropolitan area along with Osaka and Kobe. , the ...

and

Nara The National Archives and Records Administration (NARA) is an " independent federal agency of the United States government within the executive branch", charged with the preservation and documentation of government and historical records. It ...

. It is a perennial that produces thick evergreen leaves, which are ovate-orbicular and have a subhastate base. It produces ground-level maroon flowers, that are pollinated by insects. The flowering tube is prominently constricted at its apex. It blooms in April. It forms colonies on the forest floor, where it often grows co-occurs with ''

Ainsliaea cordifolia ''Ainsliaea'' is a genus of flowering plants in the family Asteraceae described as a genus in 1838. ''Ainsliaea'' is native to East Asia, the Indian Subcontinent, and Southeast Asia Southeast Asia, also spelled South East Asia and South-Ea ...

'', with which it bears a resemblance. File:Asarum asperum2 (cropped).jpg, Detail of flowers

References

{{Taxonbar, from=Q15545355 asperum Endemic flora of Japan Plants described in 1932