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Home Topics Infectious Diseases Infections A-Z Ticks Tick Taxonomy

Tick Taxonomy

Ticks feeding

Ticks are blood-feeding ectoparasites, closely related to mites and more distantly to spiders and scorpions. Both mites and ticks belong to the subclass Acari within the class Arachnida; the Acari are the only parasitic arachnids.

Like all arachnids, the adults are characterised as having four pairs of legs (tick larvae have three pairs), two pairs of appendages associated with the mouth (chelicerae and palps), and an absence of wings and antennae.

There are two main families of ticks within the sub-order Ixodida: Ixodidae (hard ticks) and Argasidae (soft ticks). Hard ticks are so called because of the presence of a tough outer scutum, or shield which soft ticks lack.

Hard tick 
Hard tick

Soft tick 
Soft tick

The many tick records collected during the 20th century were collated by the Biological Records Centre (BRC) [external link]. This data source suggests that 20 species of tick are considered to be resident in GB. The majority (17 species) belong to the family Ixodidae which can be further separated into the following genera: Ixodes, Haemaphysalis and Dermacentor. The three remaining species belong to the family Argasidae in two genera: Argas and Carios.

A number of other tick species belonging to the genera: Aponomma, AmblyommaHyalomma, and Rhipicephalus have been recorded following importation on a variety of hosts including migratory birds, humans, companion animals, livestock and reptiles; however, there is no evidence to support their ongoing survival and long-term establishment in GB.