Rotifer

A microscopic animal with spinning wheel-like cilia around its mouth/Microscopic Life

Rotifers are microscopic aquatic animals, typically 100 to 500 micrometers long, named for the spinning, wheel-like ring of cilia (the corona) around their mouths that draws in food and creates the illusion of rotation. Despite their tiny size, rotifers have a complete digestive system with a mouth, stomach, and intestine. Some species, called bdelloid rotifers, have reproduced entirely without sex for over 50 million years. Rotifers can survive extreme conditions through cryptobiosis: when dried out, they enter a state of suspended animation and can revive years later when water returns. They are found in nearly every freshwater habitat on Earth.