Wolffia, commonly referred to as watermeal and misidentified as duckweed, is officially the world’s smallest flower, with each bloom weighing about as much as two grains of sand. It takes about 5,000 of these teeny-tiny flowers to fill a thimble, and they’re amazingly small when seen against the grooves in a human fingerprint. Woffia sometimes grow in colonies that form a dense-looking mat on sheltered waters. The only way to identify the exact species of a wolffia flower is to view it under a microscope.
Each wolffia flower has a single pistil and stamen and produces the world’s smallest fruit, called a utricle. It has no leaves, stem or roots, floating freely in quiet freshwater lakes and marshes. Woffia is highly nutritious, serving as food for fish and waterfowl in nature and occasionally cultivated for use as livestock feed or even human cuisine. It’s eaten as a vegetable in Burma, Laos and Thailand.
Via Dr. Stefan Gruenwald