Premium
Molecular phylogeny and timing of radiation in Lessonia (Phaeophyceae, Laminariales)
Author(s) -
Martin Peter,
Zuccarello Giuseppe C.
Publication year - 2012
Publication title -
phycological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.438
H-Index - 44
eISSN - 1440-1835
pISSN - 1322-0829
DOI - 10.1111/j.1440-1835.2012.00658.x
Subject(s) - biology , paraphyly , monophyly , disjunct , biological dispersal , genus , evolutionary biology , phylogenetics , zoology , ecology , population , genetics , clade , gene , demography , sociology
Summary The genus L essonia B ory de S aint‐ V incent is distributed solely in the S outhern H emisphere, with four species found in S outh A merica and five in A ustralasia. Our goal was to determine the evolutionary relationships between the L essonia species of the two disjunct areas and hypothesize dispersal patterns and timing of radiation. We combined mitochondria, plastid and nuclear markers in a comprehensive dataset from multiple individuals per known species. Furthermore, for some species we added samples from multiple populations to take account of their widespread distribution over known bioregions. In all analyses the A ustralasian L essonia formed a monophyletic group and in most analyses the S outh A merican species form a paraphyletic grade. Delimitations of the accepted species are highly supported except for L . variegata J . A gardh and L . nigrescens B ory de S aint‐ V incent. We showed for the first time four lineages for the N ew Z ealand endemic L essonia variegata with an unexpected high level of genetic differentiation. Our analysis cannot resolve whether the dispersal of the common ancestor of this genus was from the A mericas to A ustralasia or vice versa . Molecular clock analysis suggested that a sudden radiation took place in A ustralasia c. 3.5 Mya when almost all A ustralasian species diverged within a time frame of only 35 000 years.