Chloroplast genomes as a tool to resolve red algal phylogenies: a case study in the Nemaliales

Obtaining strongly supported phylogenies that permit confident taxonomic and evolutionary interpretations has been a challenge in algal biology. High-throughput sequencing has improved the capacity to generate data and yields more informative datasets. We sequenced and analysed the chloroplast genomes of 22 species of the order Nemaliales as a case study in the use of phylogenomics as an approach to achieve well-supported phylogenies of red algae.Australian Research Council/[FT110100585]/ARC/AustraliaAustralian Biological Resources Study/[RFL213-08]/ABRS/AustraliaMillennium Scientific Initiative/[NC120030]/MSI/Nueva JerseyUniversity of Melbourne///AustraliaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR

Une nouvelle espèce aplatie de <I>Gracilaria</I> (Gracilariales, Rhodophyta) récoltée à Taiwan

Une espèce nouvelle de Gracilaria, G. huangii est décrite du sud de l\u27île de Taïwan. Gracilaria huangii est principalement caractérisée par de nombreux lobes ou feuillets le long des marges et sur la surface des lames, et une absence ou presque-absence des cellules nutritives tubulaires. L\u27analyse moléculaire basée sur le rbcL des espèces aplaties avec les marges épineuses et les conceptacles spermatangiaux de type textorii appuie la proposition de cette nouvelle espèce.A new, flattened species of Gracilaria, G. huangii, is described from southern Taiwan in the warm water region of the west Pacific Ocean. Gracilaria huangii is mainly characterized by numerous lobes or bladelets along the margins and on the surface of the blades, and a lack or near absence of tubular nutritive cells. The molecular analysis based on the plastid encoded rbcL gene of the flattened species with spiny margins and the textorii -type spermatangial conceptacles supports the proposal of this new species.</p

Systematic revision of the widespread species Sarcodia ceylanica (Sarcodiaceae, Rhodophyta) in the Indo-Pacific Oceans, including S. suiae sp. nov.

The marine red algal genus Sarcodia possesses single to several flattened blades, composed of a central layer of medullary filaments, with some stellate cells remaining, flanked by two layers of subspherical to stellate cortical cells. Among the described species, S. ceylanica, previously regarded as a synonym of S. montagneana, is characterised by erect thalli composed of subdichotomously branched blades and has been widely reported from the Indian and western Pacific Oceans. Collections from various localities in the Indo-Pacific regions included many specimens fitting this broad concept of S. ceylanica but differed in blade morphology and were difficult to assign to any named species with confidence. In order to delineate the species boundaries within the suite of the specimens that morphologically resemble S. ceylanica and to clarify the phylogenetic significance of the morphological features used for separating species of Sarcodia, we used rbcL sequences to infer phylogenetic relationships among the available specimens. RbcL sequence analyses showed that the distribution of S. ceylanica is most likely restricted to its type locality Sri Lanka. The collections of S. 'ceylanica' analysed from Taiwan, Japan and Kenya were split into four clades and were genetically different from those collections of S. ceylanica from Sri Lanka. The molecular results also suggested that S. montagneana is distributed only in New Zealand. In addition, one new species, S. suiae S.-M. Lin & Rodriguez-Prieto, is described to accommodate specimens of S. 'ceylanica' from Taiwan. Records of S. 'ceylanica' and S. 'montagneana' from other locations in the Indo-Pacific regions should be regarded as doubtful until detailed morphological studies and molecular analyses of freshly collected specimens become available

Systematics and biogeography of the red algal genus Yonagunia (Halymeniaceae, Rhodophyta) from the Indo-Pacific including the description of two new species from Taiwan

Carpopeltis maillardiihas been regarded as a widely distributed species in the Indo-Pacific region. In this study, we analyzed the genetic diversity ofC. maillardiiand related species collected from Taiwan and the Indian Ocean based onrbcL sequences, in order to elucidate species boundaries, diversity, and biogeographic patterns. Our analyses show thatC. maillardiispecimens are only distantly related to the genusCarpopeltis(type:C. phyllophora) but instead form a clade together with species ofYonagunia. We therefore propose the new combinationYonagunia maillardiicomb. nov. In addition, two new species (Yonagunia palmatasp. nov. andYonagunia taiwani-borealissp. nov.) are described from Taiwan. The close relationship ofYonaguniatoGrateloupiais corroborated by detailed observations of the female reproductive structures, which demonstrate that the development of auxiliary cell ampullae before and after diploidization is similar to that ofGrateloupiasensu stricto. Namely, the ampullae are composed of only two orders of unbranched filaments in which only a few ampullar cells are incorporated into a basal fusion cell after diploidization of the auxiliary cell and the pericarp consists almost entirely of secondary medullary filaments. Of allYonaguniaspecies,Y. maillardiihas the widest distribution in the Indo-Pacific, and can be identified in the field by its relatively thin, feathery, and highly branched morphology. Most other species, including those that occur in Taiwan, are seemingly more range-restricted. Our phylogenetic analyses resulted in a well-resolved phylogeny ofYonagunia, with an origin estimated in the Eocene-Oligocene, and diversification of species mainly in the Miocene

Taxonomic Revision of Hook-Forming <i>Acrosorium</i> (Delesseriaceae, Rhodophyta) from the Northwestern Pacific Based on Morphology and Molecular Data

Cosmopolitan Acrosorium species with hook-forming thalli have been merged under the name of Acrosorium ciliolatum (Harvey) Kylin through a long and complicated nomenclatural history. We examined the specimens of ‘A. ciliolatum’ and related taxa from the northwestern (NW) Pacific, the UK, southern Spain, Australia, New Zealand, and Chile, using morphological and molecular analyses. We confirmed that these specimens are separated into four clades based on rbcL phylogeny, and the absence or presence of terminal hook-like structures represent intraspecific variation. Our results indicated that Acrosorium flabellatum Yamada, Cryptopleura hayamensis Yamada, Cryptopleura membranacea Yamada and the entities known as ‘A. ciliolatum’ in the NW Pacific are conspecific; the name A. flabellatum is the oldest and has priority. This taxon exhibits extreme variations in external blade morphology. We also confirmed that the position of the tetrasporangial sori is a valuable diagnostic characteristic for distinguishing A. flabellatum in the NW Pacific. We also discussed the need for further study of European and southern hemisphere specimens from type localities, as well as the ambiguous position of California specimens