Ticks and mites are wingless, lack antennae and usually are flat or round bodied. Adults have eight legs, although some immature stages have only six legs. All members have piercing-sucking mouthparts. Many are microscopic. Ticks only feed on blood of animals. Ticks are responsible for spreading disease organisms such as the organism that causes Rocky Mountain spotted fever in man and cattle fever in cattle. Little metamorphosis is present, because adults resemble young and no wings are present. There are usually four stages; egg, larva, nymph and adult. (The terms larva and nymph are not used the same here as in the insects.)

Arthropods in this order: lone star tick, chiggers, house dust mite.

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