title: Patterns of genetic diversity of the cryptogenic red alga Polysiphonia morrowii (Ceramiales, Rhodophyta) suggest multiple origins of the Atlantic populations.
abstract: The red alga Polysiphonia morrowii, native to the North Pacific (Northeast Asia), has recently been reported worldwide. To determine the origin of the French and Argentine populations of this introduced species, we compared samples from these two areas with samples collected in Korea and at Hakodate, Japan, the type locality of the species. Combined analyses of chloroplastic (rbcL) and mitochondrial (cox1) DNA revealed that the French and Argentine populations are closely related and differ substantially from the Korean and Japanese populations. The genetic structure of P. morrowii populations from South Atlantic and North Atlantic, which showed high haplotype diversity compared with populations from the North Pacific, suggested the occurrence of multiple introduction events from areas outside of the so-called native regions. Although similar, the French and Argentine populations are not genetically identical. Thus, the genetic structure of these two introduced areas may have been modified by cryptic and recurrent introduction events directly from Asia or from other introduced areas that act as introduction relays. In addition, the large number of private cytoplasmic types identified in the two introduced regions strongly suggests that local populations of P. morrowii existed before the recent detection of these invasions. Our results suggest that the most likely scenario is that the source population(s) of the French and Argentine populations was not located only in the North Pacific and/or that P. morrowii is a cryptogenic species.
authors.affiliation: UPMC Univ Paris 06UMI 3614 Biologie évolutive et écologie des algues Station Biologique de Roscoff Place Georges Teissier 29682 Roscoff France; CNRS UMI 3614 Biologie évolutive et écologie des algues Station Biologique de Roscoff 29682 Roscoff France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Geoffroy
authors.affiliation: UPMC Univ Paris 06UMI 3614 Biologie évolutive et écologie des algues Station Biologique de Roscoff Place Georges Teissier 29682 Roscoff France; CNRS UMI 3614 Biologie évolutive et écologie des algues Station Biologique de Roscoff 29682 Roscoff France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Destombe
authors.affiliation: Department of Biology Jeju National University 66 Jejudaehakno Jeju-si, Jeju-do 690-756 Korea.
authors.forename: Byeongseok
authors.initials: B
authors.lastname: Kim
authors.affiliation: UPMC Univ Paris 06UMI 3614 Biologie évolutive et écologie des algues Station Biologique de Roscoff Place Georges Teissier 29682 Roscoff France; CNRS UMI 3614 Biologie évolutive et écologie des algues Station Biologique de Roscoff 29682 Roscoff France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mauger
authors.affiliation: Laboratorio de Algas Marinas Bentónicas Centro para el Estudio de Sistemas Marinos (CESIMAR) Centro Nacional Patagónico (CENPAT-CONICET) Bvd. Brown 2915 Puerto Madryn U9120ACF Chubut Argentina.
authors.forename: María Paula
authors.initials: MP
authors.lastname: Raffo
authors.affiliation: Department of Biology Jeju National University 66 Jejudaehakno Jeju-si, Jeju-do 690-756 Korea.
authors.forename: Myung Sook
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Muséum National d'Histoire Naturelle (MNHN) Institut de Systématique, Biodiversité, ISYEB - UMR 7205 - CNRS, MNHN, UPMC EPHE 57 rue Cuvier CP 39 75231 Paris Cedex 05 France.
authors.forename: Line
authors.initials: L
authors.lastname: Le Gall
keywords: Polysiphonia morrowii; cox1; cryptic species; introduction pathways; rbcL; red alga