The mango seed weevil Sternochetus mangiferae (Fabricius) (Coleoptera: Curculionidae) is characterized by low genetic diversity and lack of genetic structure

The mango seed weevil Sternochetus mangiferae (Fabricius) is distributed across the major mango-producing areas of the world and causes significant economic losses of mango fruit. Despite its importance as a crop pest, we have only limited information on the population genetics of the mango seed weevil. Here, we examined the genetic diversity of this important pest using specimens intercepted by Beijing Customs District P. R. in China from 41 countries and regions. We used segments of the mitochondrial gene cytochrome c oxidase subunit I and the nuclear gene elongation factor 1-alpha to examine population genetic structure in this species. Our results showed that genetic diversity is low in S. mangiferae, with a mean genetic distance of 0.095–0.14%. Other population genetic parameters also indicated a low level of genetic diversity among samples from a large geographic range. Analysis of molecular variance revealed little population genetic structure, and mismatch distribution analyses provided evidence of a population expansion, although other demographic metrics of population expansion were nonsignificant. We suggest that the observed low level of genetic diversity and population genetic structure in S. mangiferae supports the hypothesis that the population genetics of this species has been impacted by anthropogenic transportation of mangoes and weevils.