Mosquito Diversity and Population Genetic Structure of Six Mosquito Species From Hainan Island.

Chunxiang Liu,Aihua Zheng,Qianfeng Xia,Feng Jiang,Dan Wen,Hong Lu,Zhen Zou,Yanhong Wang,Feng Cui,Qiyong Liu,Le Kang,Siping Li,Xun Kang

doi:10.3389/fgene.2020.602863

Abstract

Hainan is a tropical island in southern China with abundant mosquito species, putting Hainan at risk of mosquito-borne virus disease outbreaks. The population genetic diversity of most mosquito species on Hainan Island remains elusive. In this study, we report the diversity of mosquito species and the genetic diversity of the predominant species on Hainan. Field populations of adults or larvae were collected from 12 regions of Hainan Island in 2018 and 2019. A fragment of the mitochondrial cytochrome c oxidase subunit I (coxI) gene was sequenced from 1,228 mosquito samples and used for species identification and genetic diversity analysis. Twenty-three known mosquito species from the genera Aedes, Armigeres, Culex, Mansonia, and Anopheles and nine unconfirmed mosquito species were identified. Aedes albopictus, Armigeres subalbatus, and Culex pipiens quinquefasciatus were the most prevalent mosquito species on Hainan. The regions north of Danzhou, Tunchang, and Qionghai exhibited high mosquito diversity (26 species). The order of the total haplotype diversity and nucleotide diversity of the populations from high to low was as follows: Culex tritaeniorhynchus, Ar. subalbatus, Culex pallidothorax, Culex gelidus, Ae. albopictus, and C. p. quinquefasciatus. Tajima’s D and Fu’s Fs tests showed that Ae. albopictus, C. p. quinquefasciatus, C. tritaeniorhynchus, and C. gelidus had experienced population expansion, while the Ar. subalbatus and C. pallidothorax populations were in genetic equilibrium. Significant genetic differentiation existed in the overall populations of Ae. albopictus, Ar. subalbatus, C. p. quinquefasciatus, and C. pallidothorax. The Ae. albopictus populations on Hainan were characterized by frequent gene exchange with populations from Guangdong and four other tropical countries, raising the risk of viral disease outbreaks in these regions. Two subgroups were reported in the Ar. subalbatus populations for the first time. Our findings may have important implications for vector control on Hainan Island.

Highlights

Hainan Island is located in southern China and has an area of 33,920 km2
Twentythree known mosquito species in five genera were identified in the two years of the investigation in Hainan (Table 1), including Ae. albopictus, Ae. aegypti, Aedes vexans, Aedes malayensis, Ar. subalbatus, C. p. quinquefasciatus, Culex gelidus, Culex vishnui, C. tritaeniorhynchus, Culex pallidothorax, Culex fuscanus, Culex fuscocephala, Culex pseudovishnui, Culex sitiens, FIGURE 1 | Distribution of mosquito species on Hainan
C. p. quinquefasciatus and Ar. subalbatus were second to Ae. albopictus in terms of their distribution across the island

Summary

Introduction

Hainan Island is located in southern China and has an area of 33,920 km. Hainan has become a China Pilot Free Trade Zone, with increasing international tourism and commercial trade, under the Belt and Road policy. The natural and cultural conditions of Hainan result in abundant mosquito species. A total of 44 mosquito species in 9 genera have been reported in Hainan based on classical morphological classification, among which 28 species have available molecular markers, such as mitochondrial cytochrome c oxidase subunit I (coxI) gene sequences (Zhan et al, 2000; Wang et al, 2012; Sun et al, 2014; Lian et al, 2015). The distribution and population genetic diversity of most mosquito species in Hainan have not been reported

Methods

Results

Conclusion