Predatory mite. Coloured scanning electron micrograph (SEM) of a predatory mite. Mites are small arthropods belonging to the subclass Acari and the class Arachnida. Mites are among the most diverse and successful of all the invertebrate groups. Mites with pronounced palps and long legs, the front pair facing forward, are typically predatory. Magnification: x 100 when printed at 10 centimetres wide.