About Arisaema heterophyllum Blume
Arisaema heterophyllum Blume has depressed globose, tubular roots with a diameter of approximately 2–6 cm. Its leaves are usually solitary, around 30–60 cm long, with glaucous petioles that sheath near the pseudostem. Leaves are divided gently; they are dull green on the upper (adaxial) surface and pale green on the lower (abaxial) surface. Each plant has 4 or 5 cataphylls and 11 to 21 leaflets total. The central leaflet measures 3–15 cm long and 0.7–5.8 cm wide, while outermost leaflets are smaller. The gap between adjacent leaflets is about 0.5–5 cm. Leaflets come in a range of shapes including oblanceolate, oblong, and linear-oblong, with both cuneate base and cuneate apex. The flower peduncle is 50–80 cm long, usually longer than the petiole. The flower’s spathe tube is cylindrical, 3.2–8 cm long and 1–2.5 cm wide; it is glaucous on the outside and whitish green on the inside, with a slightly recurved throat. The flower spadix is either bisexual, or monoecious and male. On bisexual spadices, the female section has a punctate stigma, a clear distinct style, and a globose ovary holding 3 to 4 ovules, while the male section holds sterile flowers. On male spadices, anther thecae dehisce through apical slits. The pale white, sigmoid appendix is up to 20 cm long, ascending, and tapers gradually from a sessile base to a sharp apex. Flowering typically begins in April or May, and fruiting occurs from July to September. Fruits are cylindrical yellowish-red or red berries, usually containing one seed. Arisaema heterophyllum is native to East Asia, including China, Inner Mongolia, Japan, and Korea. In China, it occurs across most provinces except the Northwest region and Tibet. In Japan, it is found in Honshu and Kyushu. This species grows in shaded, moist locations including evergreen and deciduous riparian forests, shrublands, inland wetlands, and grasslands. It is closely associated with floodplains and prefers humus-rich, well-draining soil. Its tubers cannot tolerate low temperatures. In Japan, it is classified as a threatened species due to the loss of riparian forest along the major rivers of the Kanto Plain. Many species in the genus Arisaema are used for medicinal purposes in Chinese traditional medicine.
