Evolution and phylogeography of Halimeda section Halimeda (Bryopsidales, Chlorophyta)

Nuclear ribosomal and plastid DNA sequences of specimens belonging to section Halimeda of the pantropical green seaweed genus Halimeda show that the group under scrutiny contains many more genetically delineable species than those recognized by classical taxonomy. Discordances between phylograms inf...

Full description

Saved in:
Bibliographic Details
Published in:Molecular phylogenetics and evolution 2005-12, Vol.37 (3), p.789-803
Main Authors: Verbruggen, Heroen, Clerck, Olivier De, Schils, Tom, Kooistra, Wiebe H.C.F., Coppejans, Eric
Format: Article
Language:English
Subjects:
Base Composition
Base Sequence
Bayes Theorem
Biogeography
Chlorophyta
Chlorophyta - cytology
Chlorophyta - genetics
Cluster Analysis
Demography
DNA, Ribosomal - genetics
Evolution
Geography
Halimeda
Incomplete lineage sorting
Indian ocean
Likelihood Functions
Marine speciation
Models, Genetic
Molecular Sequence Data
Phylogeny
Plastids - genetics
Reticulate evolution
Sequence Analysis, DNA
Species Specificity
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Nuclear ribosomal and plastid DNA sequences of specimens belonging to section Halimeda of the pantropical green seaweed genus Halimeda show that the group under scrutiny contains many more genetically delineable species than those recognized by classical taxonomy. Discordances between phylograms inferred from nuclear and plastid DNA sequences suggest that reticulate evolution has been involved in speciation within the clade. Nonetheless, our data do not allow ruling out certain alternative explanations for the discordances. Several pseudo-cryptic species are restricted to the margins of the generic distribution range. In a clade of H. cuneata sibling species from widely separated subtropical localities in the Indian Ocean, the South African sibling branches off first, leaving the Arabian and West Australian species as closest relatives. We hypothesize that geographic isolation of the siblings may have taken place following Pleistocene or Pliocene periods of climatic cooling during which subtropical species occupied larger distribution ranges. A more basal separation of Atlantic, Indo-Pacific, and Mediterranean species indicates vicariance. The alternative events that could have caused this vicariance are discussed.
ISSN:1055-7903
1095-9513
DOI:10.1016/j.ympev.2005.06.015