A phylogenetic study was conducted of species of Halymeniaceae from New Zealand presently placed in Aeodes or Pachymenia, based on maximum-likelihood (ML), maximum-parsimony (MP), and Bayesian analyses of rbcL and nuclear internal transcribed spacer (ITS) rDNA sequences. We used molecular and morphological data in combination with exhaustive sampling of herbarium collections to clarify the taxonomy and distributions of New Zealand members of Pachymenia and Aeodes. Our study confirms the presence of three erect species of Pachymenia on the New Zealand mainland, and we resurrect the name Pachymenia dichotoma J. Agardh for the widely distributed, southernmost species. Species of Aeodes from South Africa are shown to be closely related to Pachymenia carnosa (J. Agardh) J. Agardh, the type species of Pachymenia, and are accordingly transferred to Pachymenia.
Keywords: Aeodes; Halymeniaceae; ITS; New Zealand; Pachymenia; Pachymenia dichotoma; Pachymenia lusoria; Pachymenia orbitosa comb. nov.; Pachymenia ulvoidea comb. nov.; Rhodophyta; rbcL.
© 2009 Phycological Society of America.