Lens is a taxonomically complex genus of four species, all native to the Mediterranean area, West-Asia and parts of Africa. One species, Lens culinaris, is an economically important crop (lentil). It is widely cultivated in the warmer areas of the world for its seeds or as flour.
Species of Lens are sometimes included in a broadly circumscribed genus Vicia. However, recent taxonomists tend to accept it as a genus of its own.
Additional alien: Lens nigricans (Bieb.) Godr. (syn.: Vicia nigricans (Bieb.) Coss. et Germ.) (Medit., SW-As., grain alien?).
Chefranova Z.V. (1971) Obzor vidov roda Lens Mill. (Conspectus specierum generis Lens Mill.). Novosti Sist. Vyssh. Rast. 8: 184-191.
Ferguson M.E., Maxted N., Van Slageren M. & Robertson L.D. (2000) A re-assessment of the taxonomy of Lens Mill. (Leguminosae, Papilionoideae, Viceae). Bot. J. Linn. Soc. 133(1): 41-59.
Ladizinsky G. (1984) The biological species of the genus Lens L. Botanical Gazette 145: 253-261.