[1] Sometimes alternatively referred to as wheel animalcules, rotifers feature a characteristic circular arrangement of cilia at their front ends that is reminiscent of a turning wheel when they are in motion.

[1] Rotifers have a characteristic circular arrangement of cilia at their front ends.

These cilia are used to bring food particles, including bacteria, debris and small protozoans, towards the mouth.

[2] A mastax, a jaw-like structure, grinds the food as it enters the stomach.

Excretory structures known as flame cells create a current that drains them into the intestines or the bladder.