Premium
GENE SEQUENCE DIVERSITY AND THE PHYLOGENETIC POSITION OF ALGAE ASSIGNED TO THE GENERA PHAEOPHILA AND OCHLOCHAETE (ULVOPHYCEAE, CHLOROPHYTA) 1
Author(s) -
O'Kelly Charles J.,
Wysor Brian,
Bellows Wendy K.
Publication year - 2004
Publication title -
journal of phycology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.85
H-Index - 127
eISSN - 1529-8817
pISSN - 0022-3646
DOI - 10.1111/j.1529-8817.2004.03204.x
Subject(s) - biology , ulvophyceae , phylogenetic tree , clade , lineage (genetic) , botany , phylogenetics , molecular phylogenetics , algae , chlorophyta , evolutionary biology , gene , genetics
The phylogenetic position of microfilamentous marine green algae assigned to the species Phaeophila dendroides , Entocladia tenuis ( Phaeophila tenuis , and Ochlochaete hystrix was examined through phylogenetic analyses of nuclear‐encoded small subunit rDNA and chloroplast‐encoded tuf A gene sequences. These analyses placed the P. dendroides strains within the Ulvophyceae, at the base of a clade that contains representatives of the families Ulvaceae, Ulvellaceae, and the species Bolbocoleon piliferum , supporting an earlier hypothesis that P. dendroides constitutes a distinct lineage. Substantial divergence in both nuclear and plastid DNA sequences exists among strains of P. dendroides from different geographic localities, but these isolated strains are morphologically indistinguishable. The lineage may have an accelerated rate of gene sequence evolution relative to other microfilamentous marine green algae. Entocladia tenuis and O. hystrix are placed neither in the P. dendroides clade nor in the Ulvellaceae as previous taxonomic schemes predicted but instead form a new clade or clades at the base of the Ulvaceae. Ruthnielsenia gen. nov. is proposed to accommodate Kylin's species, which cannot be placed in Entocladia (= Acrochaete ), Phaeophila , or Ochlochaete . Ruthnielsenia tenuis (Kylin) comb. nov., previously known only from Atlantic coasts, is reported for the first time from the Pacific coast of North America (San Juan Island, WA, USA). Isolates of R. tenuis from the Atlantic and Pacific coasts of North America have identical small subunit rDNA and tuf A gene sequences.