Species with Broad Distributions

Abstract

Data for broadly distributed species of Ixodidae appear in Table 1. There are 22 hard tick species with broad distributions, defined here as tick species that are found in three or more zoogeographic regions, lands around the poles, remote islands, and combinations of these categories. There are also three species that have attained their current broad distribution due to human activities (Rhipicephalus annulatus, R. australis, and R. microplus). Another species with an allegedly broad distribution is Haemaphysalis cornigera, but we feel that this species has been inadequately defined and have therefore excluded it from Table 1. Similarly, Rhipicephalus sanguineus and R. turanicus require further taxonomic investigation before we can say whether their distributions are broad. Our analysis yields 18 species whose broad distribution is not obviously related directly to human activities and whose identity can be ascertained, although some of these may yet represent species groups. Ixodes is again the predominant genus, with seven species in this category, followed by Haemaphysalis with five of the 18 species, Hyalomma with three, Amblyomma with two and Rhipicephalus with one species.