Ticks belong to the class Arachnida, which includes spiders, scorpions, and mites.  Ticks go through four life stages: egg, larvae, nymph, and adult.  The larvae have six legs while the nymphs and the adults have eight.  Ticks are divided into two families, “soft” and “hard” ticks. The only sources of nutrition that ticks use is the blood sucked from their hosts.

The front part of a tick consists of the “head” area and the mouthparts.  The mouthparts have a central structure, the hypostome, which is shaped like a blunt harpoon, flat on the tops and curved on the bottom where many sharp barbs are located.

A tick pushes its hypostome into a hole in the skin of a host that has been made by sharp teeth in the front of the hypostome.  The barbs anchor the tick to the skin and make it difficult to pull the tick out.  Some ticks also produce a cement-like substance that helps anchor them to the host.  Sharp teeth at the front of the hypostome cut blood vessels under the skin, causing the blood to form a pool.  The tick then sucks this blood into its gut through the hypostome. To keep the blood from clotting, ticks inject a kind of anticoagulant into the blood pool.  The saliva may also contain disease organisms, such as Borrelia burgdorferi which causes Lyme disease.

Ticks are found wherever hosts are found.  Some ticks feed on only one type of host, while others suck blood from many different animals.  Hard ticks, when not feeding on a host, usually live on the ground, in grassy meadows, sage brush and other types of weeds and plants.  There they wait for a host to come by and from the tips of the grasses, they attach to a host.

The most common tick found in Utah is the Pacific Coast tick (Dermacentor occidentalis).  The tick carries tularemia and is the suspected carrier of the Rocky Mountain Spotted Fever and Colorado Tick Fever. 

Material Sources: Los Angles County West Vector Control District www.lawestvector.org

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