A genus of hard ticks (family Ixodidae), many species of which are parasitic on humans and animals; they are characterized by an anal groove surrounding the anus anteriorly, absence of eyes and festoons, and marked sexual dimorphism; about 40 species have been described from North America. [G. i., sticky, like bird-lime, fr. ixos, mistletoe, + eidos, form]
- I. dammini a species that is a vector of Lyme disease (Borrelia burgdorferi) and human babesiosis (Babesia microti) in the U.S. Bites causing Lyme disease in humans are from nymphal ticks about the size of a pencil point, infected with B. burgdorferi from white-footed field mice. Adult ticks complete their two-year life cycle feeding on deer.
- I. pacificus the California black-legged tick, a species that is the vector of Lyme disease in the western U.S.
- I. persulcatus the taiga tick, a Eurasian species that is a vector for Russian spring-summer encephalitis and Lyme disease.
- I. ricinus the castor bean tick, a Eurasian species that infests cattle, sheep, and wild animals, and transmits the piroplasm Babesia divergens, the tick-borne encephalitis virus, and the Lyme disease bacterium.
- I. scapularis the black-legged or shoulder tick, a species found on animals in the southern and eastern U.S.; is the primary vector of Lyme disease in the U.S.
- I. spinipalpis a species parasitic on wild rodents in British Columbia and the vector of Powassan virus in mice of the genus Peromyscus.
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Ix·o·des .ik-'sō-(.)dēz n a widespread genus of ixodid ticks (as the deer tick) many of which are bloodsucking parasites of humans and animals, and sometimes cause paralysis or other severe reactions
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n.
a genus of widely distributed parasitic ticks. Several species are responsible for transmitting Lyme disease, tularaemia, Queensland tick typhus, and Russian spring-summer encephalitis. The bite of a few species can give rise to a serious paralysis, caused by a toxin in the tick's saliva.
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Ix·o·des (ik-soґdēz) [Gr. ixōdes like bird-lime] a genus of parasitic ticks of the family Ixodidae.Medical dictionary. 2011.