Lycium L.
Genus composed of about 88 species, distributed mainly through dry and even desert areas of the New World, with about 25 species that are native to Africa. In North Africa it is represented by 4 native species (L. europaeum, L. intricatum, L. shawii and L. schweinfurthii) and 2 introduced species, that a good distinction should be made so as not to make mistakes in the management of natural ecosystems.
L. barbarum L. (L. halimifolium Mill., L. vulgare Dunal). It is differentiated by its flowers, with highly exserted stamens, showing outside the corolla about the same length as the calyx and corolla combined. Corolla with larger lobes, 3.8-6(7) mm, the same size as the corolla tube. Fruit also red but elongated, oblong (they are the popular goji berries). Native to China, it is grown in gardens for its ornamental value and it is adventitious and apparently naturalised in many coastal areas of Morocco, Algeria, Tunisia and Egypt, including the Sinai Peninsula.
L. afrum L.. It is also a spiny shrub up to 2 m in height, with leaves on the stems and spines in fascicles of 5-12, (11)14-18(24) × 0.8-2 mm, linear or narrowly oblong, with apex acute or subobtuse, succulent, glaucous, glabrous. Flowers solitary, with pedicel 5-10(13) mm, erect-patent when flowering and reflexed when fruiting. Calyx 4-6(8) × 4.5 mm, campanulate or slightly tubular, with 5 lobes c. 1.5 mm, subequal, erect, acute. Corolla with fused petals, (13)15-20 × 5-8 mm, dark brown or red-violet, infundibuliform or tubular, glabrous on the outside, laxly pilose on the inside, with 5 lobes 2-3 mm, from broadly ovate to suborbicular, obtuse, patent. Stamens reaching the mouth of the corolla, inserted to the middle of the corolla tube 7-10 mm from the base, with filaments 7-8 mm, hairy at the base. Style 12-18 mm, reaching the mouth of the corolla. Fruit a berry 8-13 × 8-10 mm, spherical or slightly ellipsoid, very dark red, almost black. Seeds 1.5-2 mm, subdiscoid to ovoid. Species from areas of the western part of southern Africa that have winter rainfall. It grows in coastal sands and sandy dunes and low mountain slopes. It is cultivated as an ornamental for its flowers, and in some areas is has escaped from cultivation and is now apparently naturalised in other parts of Africa and around the world.
Venter, A. M. 2000. Taxonomy or the genus Lycium L. (Solanaceae) in Africa. Ph.D. Thesis. University of the Orange Free State, Bloemfontein.
Key to species
1 Stamens inserted in lower half of the corolla tube, clearly exserted. Corolla lobes 3.8-6(7) mm, reflexed or patent Lycium barbarum
1 Stamens inserted in middle or slightly above middle of the corolla tube, included or slightly exserted. Corolla lobes 2-4 mm, patent 2
2 Staminal filaments hairy at the base. Leaves linear or narrowly oblong Lycium afrum
2 Staminal filaments glabrous. Leaves narrowly elliptic, elliptic, narrowly spatulate, obovate or narrowly obovate 3
3 Corolla infundibuliform, with wide tube, less than 4 times the length Lycium europaeum
3 Corolla hypocrateriform or slightly infundibuliform, with narrow tube, 4-6 times the length of lobes 4
4 Cáliz tubular, de 3-5 mm. Hojas herbáceas o ligeramente carnosas. Fruto rojo Lycium shawii
4 Calyx campanulate, 1-2.5 mm. Leaves fleshy. Fruit black or red 5
5 Berries 4-5 mm, black. Corolla creamy-white, with lilac lobes. Calyx 1-1.5 mm Lycium schweinfurthii
5 Berries 3-7(9) mm, red or orange turning blackish as they dry. Corolla violet. Calyx 1.7-3 mm Lycium intricatum
Updated by: B. Valdés.