Hard tick
Hard ticks are small blood-sucking parasites belonging to the family Ixodidae and are part of the arachnid class, which includes spiders. There are over 700 species of hard ticks found globally, except in polar regions and the Sahara Desert. These ticks are characterized by a hard shield, or scutum, on their backs, distinguishing them from soft ticks. Hard ticks typically inhabit grassy and vegetative areas, where they wait for vertebrates—such as mammals, birds, and reptiles—to pass by. When a host comes within reach, the ticks attach to their skin using sharp jaws, feeding on their blood and injecting saliva to prevent clotting.
Following a feeding period, which can cause the tick's body to swell significantly, they detach and drop to the ground. Adult female hard ticks can lay thousands of eggs, and their lifecycle includes several stages: larva, nymph, and adult. Hard ticks can survive for extended periods without feeding, with some species living up to ten years. While they primarily cause itching and red rashes, hard ticks are also vectors for various diseases, including Lyme disease, Colorado tick fever, and several others. Various predators, including birds and reptiles, help control hard tick populations.
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Hard tick
Hard ticks are one of two groups of the almost 900 species of ticks. These tiny relatives of spiders are blood-sucking parasites of vertebrates, or animals with backbones, including people. Hard ticks are named for the hard shields on their backs.
Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Ixodida
Family: Ixodidae
Genus: Various (see below)
Species: Various (see below)
There are over 700 species of hard ticks across 14 genera. Species of hard ticks are known in every part of the world except perhaps the polar regions and the Sahara Desert. These tiny creatures are in the same class as the spiders. Like spiders and other arachnids, the body of each hard tick has two sections, the abdomen, and the cephalothorax. The cephalothorax is also called the prosoma. The cephalothorax includes the head region with the two pairs of mouthparts and the thorax, or mid-body region, with the eight legs with their sensory hairs. The mouthparts are the chelicerae for cutting and the pedipalps for sensing and helping to feed. The abdomen, also known as the opisthosoma, is the rest of the body and contains all the other organs. In general, hard ticks have flattened, rounded, oval-shaped, or stretched bodies which are usually only a few millimeters long, but some grow to be up to one half inch (one centimeter) long.
Hard ticks are called hard ticks because of the hard shield, or scutum, which covers all or part of the back of each hard tick. Other tick species, the soft ticks, do not have scuta.
Hard ticks live in the grass and vegetation of a wide variety of habitats around the world. They wait for mammals, including people, reptiles, and birds to pass within reach. The ticks then climb on to these vertebrates, or animals with backbones, and begin sucking blood. The ticks are ectoparasites, or creatures which live and feed on the outside of other plants and animals. The animals on which hard ticks live are called hosts. The sharp jaws of the hard ticks pierce the skin of the hosts, and saliva flows into the wound to keep the blood from coagulating, or thickening and clotting, while the ticks suck it into their mouths. Although each tick may live alone, great numbers of ticks may live and feed on the same animal.
When a tick feeds, its body swells until it is like a ball and is several times its original size. Several days later, after a tick finishes feeding, it releases its jaws with which it grips its host and then drops to the ground. Having mated shortly before or after this meal, an adult female is ready to lay her 2,000 to 8,000 eggs. A female may be nearly one inch (2 1/2 centimeters) long when she is swollen with eggs. She lays one batch of eggs and then dies. The eggs hatch within two to five days into six- legged larvae, or young. The larvae find hosts and feed and then drop to the ground to molt, or shed, their skins. After molting, they are called nymphs and have eight legs. At this stage they again feed, drop to the ground, and molt into adults.
Hard ticks are able to survive for long periods, even years, without feeding. The life span of some species may be up to 10 years. However, most hard ticks live for up to two years.
Not only do hard ticks cause itching and red rashes, but they also carry disease and illnesses to people and animals. One of these common diseases is Lyme disease, which was first identified in Lyme, Connecticut, in 1975. Other diseases caused by viruses are Colorado tick fever, carried by the Rocky Mountain wood tick, and louping-ill in sheep in the British Isles and Russian spring- summer encephalitis in Europe and Asia, carried by the European castor bean tick. Diseases carried by other tick species include Rocky Mountain spotted fever, boutonneuse fever, and tularaemia, or rabbit fever.
Beetles, spiders, birds, lizards, badgers, and opossums are natural predators of hard ticks. Hard ticks do not contain any threatened species.
Bibliography
“Ticks.” Centers for Disease Control and Prevention, 31 Dec. 2017, www.cdc.gov/dpdx/ticks/index.html. Accessed 8 Apr. 2024.
“Family Ixodidae.” Montana Field Guide, fieldguide.mt.gov/displaySpecies.aspx?family=Ixodidae. Accessed 8 Apr. 2024.