[Frontiers in Bioscience 14, 2857-2877, January 1, 2009]

An overview of systematics and evolution of ticks

Santiago Nava, Alberto A. Guglielmone, Atilio J. Mangold

Instituto Nacional de Tecnologia Agropecuaria, Estacion Experimental Agropecuaria Rafaela, CC 22, CP 2300 Rafaela, Santa Fe, Argentina


1. Abstract
2. Introduction
3. Molecular markers in the study of systematics and ecology of ticks
4. Phylogeny, classification and evolution
4.1. Fossil records and hypotheses on the origin of ticks
4.2. Phylogeny of Argasidae
4.3. Phylogeny of Ixodidae
4.3.1. Ixodinae
4.3.2. Amblyomminae and Bothriocrotoninae
4.3.3. Haemaphysalinae and Hyalomminae
4.3.4. Rhipicephalinae
5. Update of tick names
5.1. Lists of names for ticks of the world
5.1.1. Update of names for Argasidae Antricola Argas Ornithodoros Nothoaspis and Otobius
5.1.2. Update of names for Ixodidae Amblyomma Bothriocroton Cornupalpatum Haemaphysalis Hyalomma Ixodes Rhipicephalus, Cosmiomma, Dermacentor, Margaropus, Nosomma and Rhipicentor
5.1.2. Update of names for Ixodidae 6. Summary and perspectives
7. Acknowledgements
8. References


All species of ticks (Acari: Ixodida) are grouped into three families: Argasidae (186 species), Ixodidae (692 species) and Nuttalliellidae (monotypic). Molecular markers have been developed and applied for tick studies along with conventional techniques. The origin of ticks is during the pre-mid Cretaceous period (with both the Argasidae and Ixodidae being established in the middle Cretaceous). Primeval hosts were probably reptiles or amphibians. The Argasidae contains two to five subfamilies according to authors but relationships among its members are far from resolved. The Ixodidae were formed by the basal Prostriata group (genus Ixodes subfamily Ixodinae) and the Metastriata group (all others genera). Conventional classifications considered Metastriata to be divided into Amblyomminae, Haemaphysalinae, Hyalomminae and Rhipicephalinae but evidences shows that part of Amblyomminae (species considered previously as "indigenous Australian Aponomma") are now members of the basal Metastriata subfamily Bothriocrotinae, and Hyalomminae are part of Rhipicephalinae. The former genus Boophilus is included as a subgenus within Rhipicephalus. The validity of tick names is discussed in relation to latest world list of ticks.