title: Host-associated genetic differentiation in a seed parasitic weevil Rhinusa antirrhini (Coleptera: Curculionidae) revealed by mitochondrial and nuclear sequence data.
abstract: Plant feeding insects and the plants they feed upon represent an ecological association that is thought to be a key factor for the diversification of many plant feeding insects, through differential adaptation to different plant selective pressures. While a number of studies have investigated diversification of plant feeding insects above the species level, relatively less attention has been given to patterns of diversification within species, particularly those that also require plants for oviposition and subsequent larval development. In the case of plant feeding insects that also require plant tissues for the completion of their reproductive cycle through larval development, the divergent selective pressure not only acts on adults, but on the full life history of the insect. Here we focus attention on Rhinusa antirrhini (Curculionidae), a species of weevil broadly distributed across Europe that both feeds on, and oviposits and develops within, species of the plant genus Linaria (Plantaginaceae). Using a combination of mtDNA (COII) and nuclear DNA (EF1-alpha) sequencing and copulation experiments we assess evidence for host associated genetic differentiation within R. antirrhini. We find substantial genetic variation within this species that is best explained by ecological specialisation on different host plant taxa. This genetic differentiation is most pronounced in the mtDNA marker, with patterns of genetic variation at the nuclear marker suggesting incomplete lineage sorting and/or gene flow between different host plant forms of R. antirrhini, whose origin is estimated to date to the mid-Pliocene (3.77 Mya; 2.91-4.80 Mya).
authors.affiliation: Centre for Ecology, Evolution and Conservation, School of Biological Sciences, University of East Anglia, Norwich, UK.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Hernández-Vera
authors.forename: Milana
authors.initials: M
authors.lastname: Mitrović
authors.forename: Jelena
authors.initials: J
authors.lastname: Jović
authors.forename: Ivo
authors.initials: I
authors.lastname: Tosevski
authors.forename: Roberto
authors.initials: R
authors.lastname: Caldara
authors.forename: Andre
authors.initials: A
authors.lastname: Gassmann
authors.forename: Brent C
authors.initials: BC
authors.lastname: Emerson
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D002467:Cell Nucleus / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D005060:Europe; D019143:Evolution, Molecular; D017344:Genes, Insect; D014644:Genetic Variation; D006239:Haplotypes; D008957:Models, Genetic; D010058:Oviposition; D010943:Plantago; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D048889:Weevils / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial