Cush-cush yam (Dioscorea trifida) — also called yampi, cush-cush, mapuey, aja or Indian yam — is the principal yam of the New World, a distinct fine-textured tuber native to the Guianas and the Amazon basin rather than to the Old World. Where the big African and Asian food yams grow as one massive underground mass, cush-cush forms a cluster of small, knobbly, finger- to fist-sized tubers under a thin brown or purplish skin. The flesh ranges from creamy white and pale yellow to a striking purple, and cooks up unusually fine, dry, floury and light — closer to a good mealy potato than to the coarse, waxy tropical yam. That delicate texture and a mild, faintly sweet, nutty-earthy taste have earned it a reputation among growers as the best-flavoured of all the cultivated yams.