An examination of Pachymenia and Aeodes (Halymeniaceae, Rhodophyta) in New Zealand and the transfer of two species of Aeodes in South Africa to Pachymenia

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. Key index words: Aeodes; Halymeniaceae; ITS; New Zealand; Pachymenia; Pachymenia dichotoma; Pachymenia lusoria; Pachymenia orbitosa comb. nov.; Pachymenia ulvoidea comb. nov.; rbcL; Rhodophyta Abbreviations: 5.8S, 5.8S ribosomal RNA; AK, Auckland War Memorial Museum Herbarium, New Zealand; AKU, University of Auckland Herbarium (held at AK); bp, nucleotide base pairs; CHR, Allan Herbarium, Christchurch, New Zealand; GTR, general-time-reversible model; ITS, internal transcribed spacer; ML, maximum likelihood; MP, maximum parsimony; MPN, Dame Ella Campbell Herbarium, Palmerston North, New Zealand; OTA, University of Otago Herbarium, New Zealand; rbcL, LSU of RUBISCO gene; TBR, tree bisection reconnection; WELT, Museum of New Zealand Te Papa Tongarewa