blood sucking acarid parasites of the order Ixodida comprising two families: the softbacked ticks (Argasidae) and hardbacked ticks (Ixodidae); ticks are larger than their relatives, the mites; they penetrate the skin of their host by means of highly specialized, hooked mouth parts and feed on its blood; ticks attack all groups of terrestrial vertebrates; in humans they are responsible for many diseases, including the transmission of Rocky Mountain spotted fever, tularemia, babesiosis, African swine fever and relapsing fever.
