The Ixodidae are the family of hard ticks or scale ticks,[1] one of the three families of ticks, consisting of over 700 species. They are known as 'hard ticks' because they have a scutum or hard shield, which the other major family of ticks, the 'soft ticks' (Argasidae), lack. They are ectoparasites of a wide range of host species, and some are vectors of pathogens that can cause human disease.[citation needed]

Ixodidae
Temporal range: Cretaceous–present
Ixodes ricinus (engorged)
Ixodes ricinus (engorged)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Ixodida
Superfamily: Ixodoidea
Family: Ixodidae
C. L. Koch, 1844

Description

edit

They are distinguished from the Argasidae by the presence of a scutum.[2] In both the nymph and the adult, a prominent gnathosoma (or capitulum, mouth and feeding parts) projects forward from the animal's body; in the Argasidae, conversely, the gnathosoma is concealed beneath the body.[citation needed]

They differ, too, in their lifecycle; Ixodidae that attach to a host bite painlessly and are generally unnoticed, and they remain in place until they engorge and are ready to change their skin; this process may take days or weeks. Some species drop off the host to moult in a safe place, whereas others remain on the same host and only drop off once they are ready to lay their eggs.[citation needed]

Classification

edit
 

There are 702 species in 14 genera.[3] The family contains these genera:[3]

Fossil genera

edit

Medical importance

edit

Many hard ticks are of considerable medical importance, acting as vectors of diseases caused by bacteria, protozoa, and viruses, such as Rickettsia and Borrelia.[2] Other tick-borne diseases include Lyme disease, babesiosis, ehrlichiosis, Rocky Mountain spotted fever, anaplasmosis, Southern tick-associated rash illness, tick-borne relapsing fever, tularemia, Colorado tick fever, Powassan encephalitis, and Q fever.[4]

See also

edit

References

edit
  1. ^ "Ixodidae". NCBI taxonomy. Bethesda, MD: National Center for Biotechnology Information. Archived from the original on 14 May 2018. Retrieved 28 September 2017. Lineage( full ) cellular organisms; Eukaryota; Opisthokonta; Metazoa; Eumetazoa; Bilateria; Protostomia; Ecdysozoa; Panarthropoda; Arthropoda; Chelicerata; Arachnida; Acari; Parasitiformes; Ixodida; Ixodoidea
  2. ^ a b D. H. Molyneux (1993). "Vectors". In Francis E. G. Cox (ed.). Modern parasitology: a textbook of parasitology (2nd ed.). Wiley-Blackwell. pp. 53–74. ISBN 978-0-632-02585-5. Archived from the original on 2017-02-15. Retrieved 2016-11-06.
  3. ^ a b Alberto A. Guglielmone; Richard G. Robbing; Dmitry A. Apanaskevich; Trevor N. Petney; Agustín Estrada-Peña; Ivan G. Horak; Renfu Shao; Stephen C. Barker (2010). "The Argasidae, Ixodidae and Nuttalliellidae (Acari: Ixodida) of the world: a list of valid species names" (PDF). Zootaxa. 2528: 1–28. doi:10.11646/zootaxa.2528.1.1. hdl:11336/97869. Archived (PDF) from the original on 2019-07-24. Retrieved 2015-06-28.
  4. ^ "CDC - Tick-Borne Diseases - NIOSH Workplace Safety and Health Topic". www.cdc.gov. 2018-11-14. Archived from the original on 2019-07-01. Retrieved 2019-07-01.
edit