Sphenostylis is a small genus with significant and unmistakable botanical description in the family Fabaceae, sub-family Papilionoideae, tribe Phaseoleae and sub-tribe Phaseolinae. It is distinguished for possessing dorsiventrally flattened and bearded-edge stigma and the absence of aril on the seeds. Its nativity is tropical Africa, with seven species, among which only one - S. stenocarpa (Hochst Ex. A. Rich. Harms)—African yam bean—is cultivated for the edible aerial grains and subterranean tuber. The other six are S. angustifolia, S. briartii, S. erecta, S. marginata, S. schweinfurthii and S. zimbabweensis. S. angustifolia which provide fodder for ruminants, while S. erecta, S. marginata and S. schweinfurthii have food, medicinal and industrial uses. Specific economic importance of the others is unknown. S. stenocarpa, though similar to Pachyrhizus spp. is well distinguished. This chapter redresses some subjective assertions about African yam bean: it is an annual crop, endemic only to tropical Africa, the underground product is typical of root tuber, etc. It also unveils the identity, resources and biodiversity of the six wild species. Research on the agricultural and food values of most of them is rare in literature, but each could be hosting promising economic resources and genes for the improvement of the cultivated species. Exploration and conservation of the wild and the cultivated species of Sphenostylis is inevitable to reduce further genetic erosion in the genus. The prospect of genetic improvement and the value chain of African yam beans will be enhanced by wider variability within the Sphenostylis germplasm.