Genetically Depauperate and Still Successful: FewMultilocus Genotypes of the Introduced ParthenogeneticWeevil Naupactus cervinus (Coleoptera: Curculionidae) Prevail in the Continental United States

RODRUIGUERO, M.; CONFALONIERI V. A.; MACKAY SMITH, A.; DORNON, MARY KATE; ZAGOREN, ELEANOR; PALMER, ALICE; SEQUEIRA, ANDREA S.

Insects

MDPI

Lugar: Basel; Año: 2023 vol. 14

2075-4450

The Fuller’s rose weevil Naupactus cervinus has become a globally invasive pest of several ornamental plants and fruit trees. This weevil has caused severe economic losses, and eggs laid on fruit are a quarantine barrier for several countries’ exports of fruit to markets in East Asia. Previous studies revealed that a genotype with high colonization ability successfully expanded throughout most continents, even in areas of inadequate environmental conditions, where this insect performs unexpectedly well, and that parthenogenesis may have helped to expand its geographic range. Pre-existing variation might have been eroded either by natural selection, leading to fixation of this variant able to cope with different environmental conditions to those in the native range, or by repeated bottlenecks during the process of invasion. To better understand the ecology of this invasive pest, we enlarged the sampling in areas of introduction, such as the southern United States, and surveyed genetic variation through mitochondrial and nuclear sequences in 13 localities across three states. Our results indicate that the invader genotype, already identified, has also colonized the continental United States (US), supporting the hypothesis of a general-purpose genotype capable of coping with adverse conditions and enlarging its geographical range. Parthenogenesis, and its associated lack of recombination, may help in maintaining a general-purpose genotype that facilitates the colonization of distant, unsuitable areas. However, demographic advantages linked to parthenogenesis as the sole mode of reproduction are also possible.