Plants herbs, annual or perennial and scrambling or trailings, with both staminate and pistillate flowers or unisexual, only staminate or pistillate flowers being present, with tendrils; tendrils lateral to the leaf bases, usually simple, rarely bifid; plants . Leaves simple. Flowers unisexual, usually small to medium sized, rarely large. Staminate flowers solitary or in small clusters; hypanthia campanulate, more or less setulose; sepals 5, usually small, narrow; petals 5, yellow, united near the base; stamens 3, with anthers having 2 thecae, 1 with aan anther of only 1 theca, inserted on the middle of the hypanthium; filaments short. Pistillate flowers solitary; perianths similar to those of staminate flowers; disks angular, surrounding the base of the styles; ovaries usually with soft, setiferous spines or pustules, less often smooth and densely pubescent; ovules numerous, horizontal; stigmas 3. Fruits subglobose to cylindric, firmly fleshy, smooth or with sparse to dense setiferous pines, tubercles, or pustules towards the end; seeds ovate or elliptic in outline, smooth, compressed.
Cucumis includes about 30 species. It is native to the tropics of the Old World, being most aboundant in tropical and southern Africa.