Further thoughts on the taxonomy and vector role of Rhipicephalus sanguineus group ticks.

Rhipicephalus sanguineus is a tick species described in 1806 by Latreille, based on specimens probably collected in France. However, this is a taxon with uncertain morphological definition and recent studies have gathered irrefutable evidence supporting the existence of a cryptic species-complex under the name 'R. sanguineus', whose number of sibling species around the world has yet to be ascertained. This fact is of great medical and veterinary concern, also considering that ticks currently identified as 'R. sanguineus' have been regarded as proven or putative vectors of several pathogens infecting dogs and humans. Differences in the distribution and prevalence of some of these microorganisms (e.g., Ehrlichia canis and Hepatozoon canis) further support the existence of distinct species under the name 'R. sanguineus' and suggest that the vector competence of these tick species may vary. This article provides an account on the taxonomy and the vector role of ticks belonging to the R. sanguineus group in the light of recent research.