Phenotypic and genotypic identification of hard ticks of the genus Haemaphysalis (Acari: Ixodidae) in Peninsular Malaysia

F. C. L. Ernieenor,A. Mariana,G. Ernna

doi:10.1007/s10493-017-0120-3

F. C. L. Ernieenor, A. Mariana + Show 1 more

Open Access

https://doi.org/10.1007/s10493-017-0120-3

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Abstract

Morphotaxonomy based on phenotypic traits of immature hard ticks (Acari: Ixodidae) is a skill challenge and has prompted many inexperienced acarologists to adopt DNA-based methods for identifying and discriminating the species. The aim of this study is therefore to utilize COI gene for verifying the morphological status of Haemaphysalis ticks in Peninsular Malaysia. A total of 19 on-host ticks collected from four localities were first identified using specific illustrated taxonomic keys that lead to the genus of Haemaphysalis. Genotypic traits of tick species were then verified molecularly based on cytochrome oxidase subunit I (COI) gene using polymerase chain reaction and direct sequencing. Clustering analysis was carried out by constructing a phylogenetic tree to determine the genetic variation and diversity of local Haemaphysalis ticks. Based on external morphological characterizations, all immature ticks were successfully identified down to the genus level only. Molecular analysis of the genotypic using COI gene revealed 16 individuals (84%) as Haemaphysalis hystricis, and three individuals as H. humerosa with sequence homology of 97–99 and 86–87%, respectively. Haemaphysalis hystricis were clustered in their respective monophyletic group in the phylogeny trees with a bootstrap of 100%. Furthermore, a low intraspecific variation (<0.3%) was observed among Malaysian H. hystricis but high interspecific value (>15%) recorded. This study morphologically and molecularly confirms the presence of H. hystricis in Malaysia and the findings will add value to the existing knowledge in identification of ticks in this country.

Highlights

In tropical countries, ticks are second important arthropods after mosquitoes that have potential to be vectors for transmission of infectious agents including bacteria, viruses and protozoan parasites
A total of 19 on-host immature ticks were collected from six species of hosts comprising Leopoldamys sabanus, Sundamys muelleri, Rattus tiomanicus, Maxomys rajah, Rhinosciurus laticaudatus and Tupaia glis (Table 1)
The unique character of Haemaphysalis ticks is their second segment of palps that were laterally produced beyond the basis capituli (Fig. 2)

Summary

Introduction

Ticks are second important arthropods after mosquitoes that have potential to be vectors for transmission of infectious agents including bacteria, viruses and protozoan parasites. Twelve genera comprising 104 species of ticks are found in Southeast Asia with the recent addition of two new species of Dermacentor (Apanaskevich and Apanaskevich 2015). In Malaysia, at least 34 tick species belonging to the genera Amblyomma, Dermacentor, Haemaphysalis, Ixodes and Rhipicephalus have been documented (Hoogstraal et al 1969; Mariana et al 2007; Petney et al 2007; Kolonin 2009). The genus is distributed globally, though the greatest diversity is found in Southeast Asia (Hoogstraal and Trapido 1966; Kolonin 2009). Haemaphysalis hystricis Supino is a three-host tick with a relatively broad host spectrum including human, domestic dogs, wild boar, pigs, buffalo and tigers (Mahara 1997; Cao et al 2000; Parola et al 2003). The tick-borne diseases of this region remain poorly characterized, mainly due to the limited expertise and accurate information on tick species found in Southeast Asia

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