The yam genus Dioscorea Plum. ex L. (Dioscoreaceae) includes some of the world's most important food and medicinal plants. The tubers and rhizomes of this tropical esculent are widely used as a staple food by various ethnic communities throughout the world including India (Kumar et al. 2017;Sheikh et al. 2017), and many species are a source of the plant steroid diosgenin (Anonymous 1952;Asha & Nair 2005). With about 630 species, Dioscorea is widely distributed in both tropical and subtropical regions of the world (Mabberley 2017).The diversity of the genus in India is considerable and many species and infraspecific taxa were described by Roxburgh (1832), Hooker (1892), Prain and