Menispermum, commonly known as moonseed, is a small genus of deciduous climbing woody vines in the family Menispermaceae (order Ranunculales). The genus comprises only two recognised species: Menispermum canadense (Canadian moonseed), native to northeastern North America, and Menispermum dauricum (Daurian or Asian moonseed), native to Northeast Asia including parts of present-day northeastern China and Mongolia.
The vines bear small dioecious flowers — male and female flowers occurring on separate plants — and produce clusters of small, grape-like drupes. The fruits superficially resemble wild grapes but are toxic: all parts of the plant contain dauricine and related isoquinoline alkaloids. Dauricine inhibits cardiac potassium channels, causing arrhythmia, and ingestion of the fruits can also produce CNS excitation, seizures, and neuromuscular arrest. Poisoning, including fatal cases in children, has been documented.
Both species have a history of medicinal use. M. dauricum has been employed in traditional medicine for skin disorders, rheumatism, and cervical cancer. M. canadense was used by indigenous and folk practitioners as a tonic, laxative, dermatological aid, and diuretic; Yellow Medicine County in Minnesota takes its name from one of this plant's common names. The plants are occasionally cultivated as ornamentals.
Etymology
The genus name Menispermum is derived from the Greek words μήν (mēn, crescent moon) and σπέρμα (sperma, seed), referring to the distinctive crescent-moon shape of the seeds. This shape also gives rise to the common name "moonseed."
Distribution
Menispermum canadense is native to northeastern North America, while Menispermum dauricum is native to Northeast Asia, particularly the region associated with the Daur people (a Mongolic-speaking group of northeastern China and adjacent areas). The common name of M. dauricum in Chinese is 蝙蝠葛 (bian fu ge).
Taxonomy Notes
Menispermum belongs to the family Menispermaceae within the order Ranunculales. It is a small genus of only two accepted species. The common name "moonseed" is also applied to some species in the related genus Cocculus within the same family.
Cultural Uses
Menispermum canadense has a documented history of use in North American herbal medicine as a tonic, laxative, dermatological aid, venereal aid, and diuretic. Yellow Medicine County in Minnesota is named after one of the plant's common names. Menispermum dauricum has been used in traditional East Asian medicine to treat skin disorders, rheumatism, and cervical cancer.
