Contrasting patterns of genetic structure and phylogeography in the marine agarophytes Gelidiophycus divaricatus and G. freshwateri (Gelidiales, Rhodophyta) from East Asia.
Gelidiophycus
East Asia
agar-producing algae
ecological niche modeling
phylogeographical inference
upper intertidal species
Journal
Journal of phycology
ISSN: 1529-8817
Titre abrégé: J Phycol
Pays: United States
ID NLM: 9882935
Informations de publication
Date de publication:
12 2019
12 2019
Historique:
received:
01
08
2018
accepted:
19
07
2019
pubmed:
8
8
2019
medline:
10
5
2020
entrez:
8
8
2019
Statut:
ppublish
Résumé
The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species.
Substances chimiques
DNA, Mitochondrial
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
1319-1334Informations de copyright
© 2019 Phycological Society of America.
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