Lycium is a genus of flowering plants in the nightshadefamily, Solanaceae.[2] The genus has a disjunct distribution around the globe, with species occurring on most continents in temperate and subtropical regions. South America has the most species, followed by North America and southern Africa. There are several scattered across Europe and Asia, and one is native to Australia.[3] Common English names for plants of this genus include box-thorn,[4]wolfberry, and desert-thorn.[5] There are about 70[3] to 80[6][7] species.
Etymology
The generic name Lycium is derived from the Greek word λυκιον (lykion), which was applied by Pliny the Elder (23-79) and Pedanius Dioscorides (ca. 40–90) to a plant known as dyer's buckthorn. It was probably a Rhamnus species and was named for Lycia (Λυκία), the ancient southern Anatolian region in which it grew.[8][9] The berry is called lycii fructus ("lycium fruit") in old Latinpharmacological texts.
Lycium are shrubs, often thorny, growing 1 to 4 meters tall. The leaves are small, narrow, and fleshy, and are alternately arranged, sometimes in fascicles. Flowers are solitary or borne in clusters. The funnel-shaped or bell-shaped corolla is white, green, or purple in color. The fruit is a two-chambered, usually fleshy and juicy berry which can be red, orange, yellow, or black. It may have few seeds or many.[4][6] Most Lycium have fleshy, red berries with over 10 seeds, but a few American taxa have hard fruits with two seeds.[7]
While most Lycium are monoecious, producing bisexual flowers with functional male and female parts, some species are gynodioecious, with some individuals bearing bisexual flowers and some producing functionally female flowers.[10]
Lycium, particularly L. barbarum, have long been used in traditional Chinese medicine.[12][13] The leaves and roots of other species of Lycium, such as L. europaeum, when mixed with water, have been used in folk medicine.[14] The fruit of L. barbatum and L. chinense, known as goji berry, is commonly consumed as a dried fruit.[12] The Chinese tonic gou qi zi ("wolfberry fruit") is made of the fruit of any of several Lycium species, and is used as a dietary supplement.[12]
Ecology
Lycium species mostly occur in arid and semi-arid climates, and a few are known from coastal zones in somewhat saline habitat types.[3]
Invasive species include L. ferocissimum, which was introduced to Australia and New Zealand and has become a dense, thorny pest plant there. It injures livestock, harbors pest mammals and insects, and displaces native species.[15]
^ abHitchcock, C. L. (1932). A monographic study of the genus Lycium of the Western Hemisphere. Annals of the Missouri Botanical Garden 19(2/3), 179-348 and 350-66. doi:10.2307/2394155 (First page image).
^"Goji Berries"(PDF). UK Food Standards Agency, Novel Foods, Additives and Supplements Division. June 2007. Archived from the original(PDF) on 20 November 2012. Retrieved 13 April 2013.
^Nissim Krispil, Medicinal Plants in Israel and Throughout the World - the Complete Guide, Or Yehuda (Israel) 2000, pp.38–39 (Hebrew)
