Watermelon (Citrullus lanatus (Thunb.), family Cucurbitaceae) is a vine-like (scrambler and trailer) flowering plant originally from southern Africa. Its fruit, which is also called watermelon, is a special kind referred to by botanists as a pepo, a berry which has a thick rind (exocarp) and fleshy center (mesocarp and endocarp). Pepos are derived from an inferior ovary, and are characteristic of the Cucurbitaceae. The watermelon fruit, loosely considered a type of melon - although not in the genus Cucumis - has a smooth exterior rind (green, yellow and sometimes white) and a juicy, sweet interior flesh (usually deep red to pink, but sometimes orange, yellow and even green if not ripe). Watermelon is thought to have originated in southern Africa, where it is found growing wild.
Contributions by Bebop, Deeceevoice, and Pollinator.