Differential interference contrast (DIC) light micrograph of a Euchlanis sp. rotifer. Also called wheel animals, rotifers are common in freshwater environments. They use their cilia (microscopic hairs) and two toe-like projections for locomotion. They are surprisingly complex on the inside: they have a brain, reproductive organs, a bladder and a digestive system. They are omnivorous, eating bacteria, debris or small protozoans. Magnification: x330 when printed 10 centimetres wide.