''Ixodes hexagonus'', also known by the common name hedgehog tick, is a

tick Ticks are parasitic arachnids of the order Ixodida. They are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, and species, but can become larger when engorged. Ticks a ...

species in the genus ''

Ixodes ''Ixodes'' is a genus of hard-bodied ticks (family Ixodidae). It includes important disease vectors of animals and humans ( tick-borne disease), and some species (notably '' Ixodes holocyclus'') inject toxins that can cause paralysis. Som ...

''. It is a parasite of the

European hedgehog The European hedgehog (''Erinaceus europaeus''), also known as the West European hedgehog or common hedgehog, is a hedgehog species native to Europe from Iberia and Italy northwards into Scandinavia and westwards into the British Isles.Harris, S. ...

Appearance

The hedgehog tick is dark brown in color, but appears light grey or white when engorged. It can be identified by the humped tarsae of its first pair of legs. The adult female has a characteristic heart- or hexagon-shaped

scutum The ''scutum'' (; :''scuta'') was a type of shield used among Italic peoples in antiquity, most notably by the army of ancient Rome starting about the fourth century BC. The Romans adopted it when they switched from the military formation of ...

; the male's scutum covers the entire body segment (idiosoma), as is typical for hard ticks. A lateral groove runs along the body segment, and becomes more evident when the tick is engorged.

Distribution

''Ixodes hexagonus'' is found widely throughout central and western Europe, and as far east as Siberia. In the United Kingdom, its distribution is sparse to the northwest, increasing in density to the southeast. As a nest-dwelling parasite of the European hedgehog, its distribution is closely associated with that of its preferred host. Hedgehogs are not its only host, however; it can also be found on foxes, mustelids, dogs and cats.

Habitat

''Ixodes hexagonus'' is endophillic; it is predominantly a nest based parasite. It spends most of its life in the nest of the main hedgehog host. Thus it is buffered from the environmental conditions experienced by many other free ranging ticks such as ''I. ricinus''.

Role in Lyme disease

The hedgehog tick is a potentially important reservoir for ''

Borrelia ''Borrelia'' is a genus of bacteria of the spirochete phylum. Several species cause Lyme disease, also called Lyme borreliosis, a zoonotic, vector-borne disease transmitted by ticks. Other species of ''Borrelia'' cause relapsing fever, and are ...

'' bacteria, the causative agent of

Lyme disease Lyme disease, also known as Lyme borreliosis, is a tick-borne disease caused by species of ''Borrelia'' bacteria, Disease vector, transmitted by blood-feeding ticks in the genus ''Ixodes''. It is the most common disease spread by ticks in th ...

. Studies indicate that both hedgehogs and ''I. hexagonus'' harbour ''Borrelia''. ''I. hexagonus'' may act as an important vector of Lyme disease, transmitting it from hedgehog hosts to other small mammals. Thus ultimately it may spread to large mammals and humans. ''I. hexagonus'' may be important in sustaining Lyme disease in urban location where hedgehogs are a frequently found small mammal.

References

hexagonus Arachnids of Africa Arachnids of Europe Arachnids described in 1815 Taxa named by William Elford Leach Lyme disease Hedgehog diseases {{tick-stub