title: New mitochondrial and nuclear evidences support recent demographic expansion and an atypical phylogeographic pattern in the spittlebug Philaenus spumarius (Hemiptera, Aphrophoridae).
abstract: Philaenus spumarius is a widespread insect species in the Holarctic region. Here, by focusing on the mtDNA gene COI but also using the COII and Cyt b genes and the nuclear gene EF-1α, we tried to explain how and when its current biogeographic pattern evolved by providing time estimates of the main demographic and evolutionary events and investigating its colonization patterns in and out of Eurasia. Evidence of recent divergence and expansion events at less than 0.5 Ma ago indicate that climate fluctuations in the Mid-Late Pleistocene were important in shaping the current phylogeographic pattern of the species. Data support a first split and differentiation of P. spumarius into two main mitochondrial lineages: the "western", in the Mediterranean region and the "eastern", in Anatolia/Caucasus. It also supports a following differentiation of the "western" lineage into two sub-lineages: the "western-Mediterranean", in Iberia and the "eastern-Mediterranean" in the Balkans. The recent pattern seems to result from postglacial range expansion from Iberia and Caucasus/Anatolia, thus not following one of the four common paradigms. Unexpected patterns of recent gene-flow events between Mediterranean peninsulas, a close relationship between Iberia and North Africa, as well as high levels of genetic diversity being maintained in northern Europe were found. The mitochondrial pattern does not exactly match to the nuclear pattern suggesting that the current biogeographic pattern of P. spumarius may be the result of both secondary admixture and incomplete lineage sorting. The hypothesis of recent colonization of North America from both western and northern Europe is corroborated by our data and probably resulted from accidental human translocations. A probable British origin for the populations of the Azores and New Zealand was revealed, however, for the Azores the distribution of populations in high altitude native forests is somewhat puzzling and may imply a natural colonization of the archipelago.
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Ana S B
authors.initials: AS
authors.lastname: Rodrigues
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Sara E
authors.initials: SE
authors.lastname: Silva
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Marabuto
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Diogo N
authors.initials: DN
authors.lastname: Silva
authors.affiliation: Department of Natural Sciences, National Museum of Wales, Cardiff, United Kingdom.
authors.forename: Mike R
authors.initials: MR
authors.lastname: Wilson
authors.affiliation: Metropolitan College of New York, New York, New York, United States of America.
authors.forename: Vinton
authors.initials: V
authors.lastname: Thompson
authors.affiliation: Biology Department, Science Faculty, Trakya University, Edirne, Turkey.
authors.forename: Selçuk
authors.initials: S
authors.lastname: Yurtsever
authors.affiliation: Department of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Antti
authors.initials: A
authors.lastname: Halkka
authors.affiliation: Azorean Biodiversity Group, Centro de Investigação e Tecnologias Agrárias dos Açores and Platform for Enhancing Ecological Research & Sustainability, Universidade dos Açores, Departamento de Ciências Agrárias, Angra do Heroísmo, Terceira, Portugal.
authors.forename: Paulo A V
authors.initials: PA
authors.lastname: Borges
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: José A
authors.initials: JA
authors.lastname: Quartau
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Octávio S
authors.initials: OS
authors.lastname: Paulo
authors.affiliation: Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal/Platform for Enhancing Ecological Research & Sustainability, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Sofia G
authors.initials: SG
authors.lastname: Seabra
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D003710:Demography; D003576:Electron Transport Complex IV / Q000235:genetics; D050259:Genes, Mitochondrial; D014644:Genetic Variation; D006239:Haplotypes / Q000235:genetics; D006430:Hemiptera / Q000235:genetics*; D006801:Humans; D016013:Likelihood Functions; D008928:Mitochondria / Q000235:genetics*; D010802:Phylogeny; D058974:Phylogeography; D011158:Population Growth; D013997:Time Factors
chemical_list: D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV