The difference between mites and insects is, taxonomically speaking, much greater than most people realize — mites are not even insects.

Insects belong to the class Insecta — six legs, body divided into three tagmata (head, thorax, abdomen), one pair of antennae, and usually have wings (not all insects have wings, but this is a primitive characteristic of the class).

Mites belong to the subclass Acari within the class Arachnida — the same major group as spiders and ticks.

Adult mites have eight legs (six in the larval stage), a body with only two tagmata (cephalothorax and abdomen, no separate head), no antennae, and no wings.

Evolutionarily speaking — mites are more closely related to spiders than to any insect.

This explains why common insecticides may be ineffective against mites — there are significant physiological and neurological target-site differences between mites and insects.

Specific acaricides (such as fluazuron, abamectin) act on targets unique to mites — whereas general insecticides may exert insufficient selection pressure on mites.

Another practical implication — most "whole-house aerosol insecticides" will not significantly reduce indoor dust mite populations — because the physiology of dust mites and their sensitivity to chemicals differ from that of cockroaches and fleas.

Controlling dust mites requires specialized environmental management strategies — allergen-proof mattress and pillow encasements, high-temperature washing, and indoor humidity control.