Revision of Abrus Adanson (Pap.) with special reference to Africa

Abrus is a small natural genus of the family Papilionaceae, containing four species, well distinguished by the presence of 9 connate stamens. As a genus it was first described by Adanson in 1763 who based it on Glycine abrus L.. In fruit this species is easily distinguished by its conspicuously red and black coloured seeds, which are used in various ways, e.g. as beads in rosaries and necklaces, for making poison and medicine. The flowers of the species in Abrus do not show any character leading to specific segregation. Characters of the pod and inflorescence are more useful. One, imperfectly known, species is recorded only from Madagascar and another is confined to tropical Africa. The other two species have a circumtropical distribution, one of these, A. fruticulosus, is widely variable in habit, in the shape of the leaves, and in the indumentum. It is not advisable to segregate the different forms of this species, which were formerly described as distinct species (such as A. schimperi, A. mollis, A. cantoniensis, etc.), as infraspecific taxa, e.g. as varieties, or as name-bearing forms.