Rhipicephalus

{{Short description|Genus of ticks}}

{{Automatic_taxobox

| image = Rhipicephalus sanguineus.jpg

| image_caption= Rhipicephalus sanguineus

| taxon = Rhipicephalus

| subdivision_ranks = Species

| subdivision = About 74–75 species, see text.

| type_species= Ixodes sanguineus

| type_species_authority=Latreille, 1806

| authority = Koch, 1844{{cite journal|last1=Koch|first1=C. L.|title=Systematische Übersicht über die Ordnung der Zecken|journal=Archiv für Naturgeschichte|date=1844|volume=10|issue=1|pages=238–239|url=https://www.biodiversitylibrary.org/page/7089013}}

}}

Rhipicephalus is a genus of ticks in the family Ixodidae, the hard ticks, consisting of about 74 or 75 species. Most are native to tropical Africa.Olwoch, J. M., et al. (2007). [http://www.ojvr.org/index.php/ojvr/article/viewFile/139/134 Climate change and the genus Rhipicephalus (Acari: Ixodidae) in Africa.] Onderstepoort J Vet Res 74(1), 45-72.

Rhipicephalus ticks are commonly called 'the brown tick' as they are mostly brown in colour.{{Cite book |last=Walker, J.B., Keirans, J.E. & Horak, I.G. |title=The Genus Rhipicephalus (Acari, Ixodidae): A Guide to the Brown Ticks of the World. |publisher=Cambridge University Press |year=2000 |isbn=0-521-48008-6}} Most adult ticks in this genus do not have colour patterns on their scutum (inornate). This makes the species difficult to distinguish from one another because most are quite similar, but individuals of one particular species can be quite variable.Beati, L. and J. E. Keirans. (2001). [http://lorenzabeati.klacto.net/index_files/REFS/Full7.pdf Analysis of the systematic relationships among ticks of the genera Rhipicephalus and Boophilus (Acari: Ixodidae) based on mitochondrial 12S ribosomal DNA gene sequences and morphological characters.] The Journal of Parasitology 87(1), 32. Ticks have traditionally been identified by examination of distinctive morphological features. Most of the characteristics used to identify species pertain to male specimens. The immature and female specimens are sometimes simply impossible to identify due to the lack of differential morphological features.{{Cite book |url=https://link.springer.com/book/10.1007/978-3-319-70642-9 |title=The Ixodid Ticks (Acari: Ixodidae) of Southern Africa |language=en |doi=10.1007/978-3-319-70642-9}}

Many Rhipicephalus spp. are of economic, medical, and veterinary importance because of their blood feeding lifestyle. They are possible vectors of many pathogens in humans and animals. They can transmit pathogens that cause animal and human diseases, such as East Coast fever, anaplasmosis, babesiosis, rickettsiosis, Boutonneuse fever, Lyme disease, Q fever, Rocky Mountain spotted fever, and Crimean–Congo hemorrhagic fever.[http://webpages.lincoln.ac.uk/fruedisueli/FR-webpages/parasitology/Ticks/TIK/tick-key/background_rhipicephalus.htm#Rhipicephalusevertsi Rhipicephalus.] Tick Identification Key. University of Lincoln. In addition to the infectious agents spread by ticks, tick bites can lead to allergic and toxic reactions.{{Cite journal |last=Ahmed |first=Jabbar |last2=Alp |first2=Hatice |last3=Aksin |first3=Muhammed |last4=Seitzer |first4=Ulrike |date=2007 |title=Current status of ticks in Asia |url=http://link.springer.com/10.1007/s00436-007-0696-3 |journal=Parasitology Research |language=en |volume=101 |issue=S2 |pages=159–162 |doi=10.1007/s00436-007-0696-3 |issn=0932-0113|url-access=subscription }}{{Cite book |last=Daniel E. Sonenshine, R. Michael Roe |url=https://www.worldcat.org/oclc/862106136 |title=Overview: Ticks, People, and Animals in Biology of ticks, Volume 1 |date=2014 |publisher=Oxford University Press |isbn=978-0-19-937927-9 |edition=Second |oclc=862106136}} A toxic reaction occur when they inject a neurotoxin with their bite that leads to tick-caused paralysis.

Boophilus was once considered a separate genus, but studies in the early 2000s resulted in Boophilus being made a subgenus of Rhipicephalus.{{cite journal |last1=Murrell |first1=Anna |last2=Barker |first2=Stephen C. |date=2003 |title=Synonymy of Boophilus Curtice, 1891 with Rhipicephalus Koch, 1844 (Acari: Ixodidae) |journal=Systematic Parasitology |volume=56 |issue=3 |pages=169–172 |doi=10.1023/B:SYPA.0000003802.36517.a0 |pmid=14707501 |s2cid=995415 }} Although Boophilus has been included in the Rhipicephalus genus, their morphology is different from the typical Rhipicephalus species.

Species familiar in the domestic environment include the brown dog tick (R. sanguineus).

==Sex pheromone studies==

A number of Rhipicephalus spp. females produce phenol and p-cresol after being fed for six days. These compounds may act as sex pheromones since these compounds were shown to be the sex pheromone of Rhipicephalus appendiculatus. {{cite journal | last1 = Wood | first1 = William F. | last2 = Leahy | first2 = Mary G.. | last3 = Galun | first3 = R. | last4 = Prestwich | first4 = G. D. | last5 = Meinwald | first5 = J. | last6 = Purnell | first6 = R. E. | last7 = Payne | first7 = J. | year = 1975 | title = Phenols as Sex Pheromones of Ixodid Ticks: A General Phenomen? | journal = J. Chemical Ecology | volume = 1 | pages = 501-509 | doi=10.1007/BF00988590}}