acarid

An acarid is a mite or a tick. These are small arachnids belonging to the subclass Acari. They are incredibly diverse, with over 50,000 described species, and are found in virtually every habitat on Earth. Acari can be parasitic, feeding on plants, animals, or even humans, or they can be free-living, inhabiting soil, water, or decaying organic matter.

Parasitic acarids can cause a range of problems. Some, like the scabies mite, burrow into the skin of their hosts, causing intense itching and irritation. Others, such as ticks, can transmit serious diseases like Lyme disease and Rocky Mountain spotted fever. Plant-feeding mites, often called spider mites, can cause significant damage to crops and gardens by sucking sap from leaves, leading to yellowing, wilting, and reduced yields.

Free-living acarids play important roles in ecosystems. Dust mites, for example, are common in homes and feed on shed human skin cells. While generally harmless, their waste products can trigger allergies in some individuals. Soil mites are crucial decomposers, breaking down organic matter and contributing to nutrient cycling in the soil. Their presence is often an indicator of a healthy soil environment. The study of mites and ticks is known as acarology.