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Despite the recent description of Stenogramma guleopoense in Korea, the issue of S. interruptum in the northwestern Pacific is still a matter of debate. We analyzed 24 rbcL sequences from specimens collected in Korea, including a longer fragment of rbcL (949 base pairs from the type of S. guleopoense, in addition to morphological observations. Phylogenetic analysis of rbcL sequence revealed a new distinct clade that differed from S. guleopoense from Korea and other species of Stenogramma. The morphology and anatomy of the Korean clade supported its distinct position in the genus Stenogramma. On the basis of these results, we describe S. coreanum sp. nov. from Korea. Stenogramma coreanum is distinguished by a combination of its large size (up to 24 cm) of dichotomous to subdichotomous branches divided up to nine times, wider blades with laciniate segments, one to two layers of cortical cells, two to three layers of medullary cells, a gradient of one to two layers of smaller cells between the corte...

A new and putatively endemic species of Hydroclathrus, Hydroclathrus rapanuii, is described from the geographically isolated Easter Island in the southeastern Pacific based on morphological and molecular phylogenetic data. It is distinguished from other Hydroclathrus by thalli of unevenly furrowed thin membranes, and angular, block-like plurangial sori. Our phylogenetic analyses indicated that H. rapanuii is closely related to the generitype Hydroclathrus clathratus. We also report on the morphology and phylogeny of Chnoospora minima from Easter I. and elsewhere in the Indo-Pacific Ocean, noting the previously unreported presence of hollow portions in its medulla. Although not collected from Easter I., we herein propose the recognition of two new genera, Dactylosiphon gen. nov. and Pseudochnoospora gen. nov., based on our three-gene phylogeny and their known morphologies and anatomies. Dactylosiphon is based on the three species currently assigned to Colpomenia (C. bullosa, C. durvillei, and C. wynnei) that are genetically and morphologically (i.e. thalli with erect and finger-like tubes arising from a common saccate base) distinct from other members of Colpomenia. The monotypic genus Pseudochnoospora is represented by the decumbent, branching, and inter-adhesive species currently known as Chnoospora implexa. With the above proposals, we further increase the genus-level diversity of Scytosiphonaceae in the Indo-Pacific Ocean.

A total of 28 strains of 19 Penicillium species were isolated in a survey of extracellular enzyme-producing fungi from macroalgae along the coast of Jeju Island of Korea. Penicillium species were identified based on morphological and β-tubulin sequence analyses. In addition, the halo-tolerance and enzyme activity of all strains were evaluated. The diversity of Penicillium strains isolated from brown algae was higher than the diversity of strains isolated from green and red algae. The commonly isolated species were Penicillium antarcticum, P. bialowiezense, P. brevicompactum, P. crustosum, P. oxalicum, P. rubens, P. sumatrense, and P. terrigenum. While many strains showed endoglucanase, β-glucosidase, and protease activity, no alginase activity was detected. There was a positive correlation between halo-tolerance and endoglucanase activity within Penicillium species. Among 19 Penicillium species, three species-P. kongii, P. olsonii, and P. viticola-have not been previously recorded in Korea.

Four species have been described in the genus Pikea (Dumontiaceae, Gigartinales): three species from North America and one species from Japan. However, the phylogeny and species delimitation in Pikea remain poorly resolved. Here we provide both rbcL and cox1 sequences for all species of Pikea, including the type of P. pinnata and a paratype of P. robusta. Our data reveal that P. californica, P. pinnata and P. yoshizakii are distinct in both data sets, but P. robusta is synonymous with the earlier-described P. pinnata. Morphological and molecular data show that Pikea from Korea is identical to P. yoshizakii and that the previous report of P. californica in Korea is a misidentification. The genus Pikea is well resolved in the main clade of the Dumontiaceae. This is the first study on the phylogeny of Pikea using rbcL and cox1 sequence data.

Twelve Acetobacter pasteurianus-related strains with publicly available genomes in GenBank shared high 16S rRNA gene sequence similarity (>99.59%), but average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) values and multilocus sequence- and genome-based relatedness analyses suggested that they were divided into four different phylogenetic lineages. Relatedness analyses based on multilocus sequences, 1,194 core genes and whole-cell MALDI-TOF profiles supported that strains LMG 1590T and LMG 1591 (previously classified as the type strains of A. pasteurianus subsp. ascendens and paradoxus, respectively) and strain SLV-7T do not belong to A. pasteurianus. Strain SLV-7T, isolated from Korean traditional vinegar, shared low ANI (

Coccophora langsdorfii (Turner) Greville (Fucales) is an intertidal brown alga that is endemic to Northeast Asia and increasingly endangered by habitat loss and climate change. We sequenced the complete circular plastid and mitochondrial genomes of C. langsdorfii. The circular plastid genome is 124,450 bp and contains 139 protein-coding, 28 tRNA and 6 rRNA genes. The circular mitochondrial genome is 35,660 bp and contains 38 protein-coding, 25 tRNA and 3 rRNA genes. The structure and gene content of the C. langsdorfii plastid genome is similar to those of other species in the Fucales. The plastid genomes of brown algae in other orders share similar gene content but exhibit large structural recombination. The large in-frame insert in the cox2 gene in the mitochondrial genome of C. langsdorfii is typical of other brown algae. We explored the effect of this insertion on the structure and function of the cox2 protein. We estimated the usefulness of 135 plastid genes and 35 mitochondrial genes for developing molecular markers. This study shows that 29 organellar genes will prove efficient for resolving brown algal phylogeny. In addition, we propose a new molecular marker suitable for the study of intraspecific genetic diversity that should be tested in a large survey of populations of C. langsdorfii.

A Gram-stain-negative and strictly aerobic bacterial strain, designated 6-4T, was isolated from forest soil in Jeju island, South Korea. Cells showing oxidase-positive and catalase-negative reactions were thin and long non-motile rods. Growth of strain 6-4T was observed at 20–35 °C (optimum, 30 °C) and pH 6.0–9.0 (optimum, pH 7.0). Strain 6-4T contained iso-C15 : 0, anteiso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH as the major fatty acids and menaquinone-7 (MK-7) as the sole isoprenoid quinone. Phosphatidylethanolamine was the major polar lipid and five unidentified aminolipids, one unidentified aminophospholipid and one unidentified lipid were also detected as minor polar lipids. The G+C content of the genomic DNA was 45.8 mol%. Strain 6-4T was most closely related to Flavihumibacter solisilvae 3-3T with a low 16S rRNA gene sequence similarity (94.2 %) and phylogenetic analysis indicated that the strain formed a distinct phylogenetic lineage from members of the genus Flavihumibacter and other closely related genera. On the basis of phylogenetic inference and phenotypic, chemotaxonomic and molecular properties, strain 6-4T represents a novel species of a new genus of the family Chitinophagaceae , for which the name Niveitalea solisilvae gen. nov., sp. nov. is proposed. The type strain of Niveitalea solisilvae is 6-4T (=KACC 18808T=JCM 31525T). An emended description of the genus Flavihumibacter is also proposed.

DNA barcoding is becoming a widely applied tool to accurately discriminate red algae. We tested the effectiveness of DNA barcoding for identification and discovery of Champia species in Korea and clarified the phylogenetic relationships using the plastid rbcL gene. As results, we described four species of Champia such as C. inkyua sp. nov., C. recta Noda, C. bifida Okamura, and C. expansa Yendo. A new species, C. inkyua, is characterized by entangled thallus, terete and irregular branches, hooked apices, and longitudinal filaments running throughout the frond periphery only. Longitudinal fila ments were composed of a complete cell with two half cells between diaphragms in the cavity. C. recta and C. bifida were reinstated with previously used names of C. parvula and C. compressa, respectively. C. recta is the first recorded species from Korea and is characterized by an erect thallus, terete and irregular branches, and straight apices. C. bifida is characterized by compressed thallus, pinnate or alternate branches, and bifid apices. C. expansa is characterized by flabellate thallus and dichotomous branches. Molecular analyses of COI and rbcL genes revealed sufficient sequence divergence to warrant species recognition in the genus Champia.

Native halophytes, such as Suaeda maritima, Limonium tetragonum, S. japonica, Zoysia sinica, and Phragmites australis were collected from the Muan salt marsh. Ninety endophytic fungi were isolated from the roots of the collected halophytes. Molecular insights inferred by internal transcribed spacer containing ITS1, 5.8s, and the ITS2 region showed that all the fungal strains belong to ten orders, i.e., Capnodiales (4.44%), Cystofilobasidiales (1.11%), Dothideales (3.33%), Eurotiales (53.33%), Glomerellales (3.33%), Hypocreales (8.89%), Mucorales (1.11%), Pleosporales (15.56%), Sordariales (1.11%), and Trichosphaeriales (1.11%). The rest (6.67%) of all fungal isolates were not identified. Ninety fungal strains were confirmed at the genus level, containing Acremonium, Alternaria, Aspergillus, Aureobasidium, Cephalosporium, Chaetomium, Cladosporium, Colletotrichum, Cryptococcus, Didymella, Dothideomycete, Emericellopsis, Epicoccum, Eupenicillium, Fusarium, Gibberella, Gongronella, Macrophoma, Microsphaeropsis, Nigrospora, Paecilomyces, Paraconiothyrium, Penicillium, Phaeomyces, Phoma, Pleosporales, Purpureocillium, and Talaromyces. Of all the endophytic fungi identified from the various halophytes, Aspergillus and Penicillium of Eurotiales had the highest abundance.

A new brown alga Petalonia tatewakii sp. nov. (Scytosiphonaceae) is described from the Hawaiian Islands based on morphological observations and phylogenetic analyses of DNA sequences of the chloroplast-encoded rbcL gene and the ITS1-5.8S-ITS2 region of the nuclear ribosomal cistron. The thalli are linear and complanate, up to 15 cm in length and 0.8 cm in width with rhizoidal filaments in the medulla. This species is morphologically distinguishable from other Petalonia species by having ascocysts among plurilocular zoidangia. Molecular phylogenetic analyses revealed that samples of P. tatewakii form a distinct clade that is sister to the clade of P. binghamiae (J. Agardh) Vinogradova. All our collections of Hawaiian Petalonia from the main Hawaiian Islands were assigned to P. tatewakii.

A new red algal parasite, Symphyocolax koreana M. S. Kim, gen. et sp. nov., has been found on a specimen of Symphyocladia latiuscula (Harvey) Yamada, a member of the tribe Pterosiphonieae of the Rhodomelaceae; this genus has never before been reported to host red algal parasites. Here, the new parasite from Korea is described in terms of vegetative and reproductive morphology. The thallus has a minute, colored polysiphonous upright axis with many branches attached by pseudoparenchymatous pulvinate bases. There are six pericentral cells, with many corticated cells in the lower part of the main branches. Trichoblasts occur on dioecious male and female gametophytes, but not on tetrasporophytes. Procarps develop on suprabasal cells of trichoblasts and consist of a four-celled carpogonial branch and two sterile cells attached to the supporting cell. Spermatangial branches are borne one per each successive segment on monosiphonous pedicels in spiral positions with fertile trichoblast. Tetrasporangia are formed one per segment in a straight series and are tetrahedrally divided. Features of the vegetative axes, procarp, spermatangial trichoblasts, and tetrasporangial branching show that the new genus is an alloparasite belonging to the tribe Polysiphonieae.

Based on morphological characters, cross-fertility and molecular systematics, two species are currently recognized in the ubiquitous temperate brown algal genus Ectocarpus: the type species E. siliculosus (Dillwyn) Lyngbye and E. fasciculatus Harvey. We studied diversity , cross-fertility and ecology of Ectocarpus in mega-tidal areas in northwest France (Western Europe) and propose to reinstate a third species, E. crouaniorum Thuret in Le Jolis. Genotyping of 67 individuals from five localities, including the type locality of E. crouan-iorum, using internal transcribed spacer 1 (ITS1) length as a marker, showed that the three species co-occurred whenever the habitat was suitable. Our survey also revealed a single putative field hybrid between E. crouaniorum and E. siliculosus, and a single individual of a further Ectocarpus genotype. In laboratory experiments, E. crouaniorum was crossed with E. siliculosus and E. fasciculatus. In 12 of 13 crosses, the zygotes did not develop (postzygotic sterility); in one experiment a viable hybrid was produced after crossing a female E. crouaniorum with a male E. siliculosus, but this hybrid was unable to form meiospores. Phyloge-netic analysis of five molecular markers from the nuclear, mitochondrial and plastid genomes (in total 1818 bp) confirmed genetic separation of the three species. Ecologically, E. crouaniorum was confined to high intertidal pools and runoffs , where the gameto-phyte was common from spring to summer. Another characteristic was that it usually occurred as an epi-phyte of up to 12 cm in length on erect thalli of Scy-tosiphon lomentaria. Sporophytes of E. crouaniorum were found all year long; they were

SUMMARY Colpomenia sinuosa is an annual brown algal species that occurs in temperate to tropical waters of the world. In order to examine the genetic diversity among populations of the species and to discuss its current distribution, we analyzed the nuclear ribosomal DNA internal transcribed spacer (ITS) region from 18 specimens of C. sinuosa, and, for comparison, plastid rbcL from the same specimens. The C. sinuosa ITS region (2141–2534 base pairs) is approximately 2.2 times the length of most other brown algae. We found a long repeated sequence of approximately 190 base pairs in the first half of the ITS1 region; five repeats in Northern Hemisphere collections and three in those from the Southern Hemisphere, which result in ITS length variation. The unequal occurrence of tandem repeats of C. sinuosa corresponds to the geographical distribution of the species. The rbcL sequences from all the specimens of C. sinuosa, except the Canary Island samples, were identical, indicating that they indeed belong to the same species.

The genus Cladosiphon Kutzing (1843) is classified into the Chordariaceae in Ectocarpales sensu lato and includes 13 species in the world (Sanson et al. 2006; Ajisaka et al. 2007). Although most of the species of Cladosiphon have been reported in Europe and Africa (Guiry and Guiry 2009), only two species, C. okamuranus Tokida and C. umezakii Ajisaka, are reported in Japan (Tokida 1942; Ajisaka et al. 2007). Cladosiphon okamuranus is very famous for foods in Japan as well as a resource of fucoidan (Nagaoka et al. 1999) and cultivate massively in Okinawa. Recently C. umezakii has been established as a new species based on morphological and molecular data in Japan (Ajisaka et al. 2007). This species is annual, growing on lower intertidal to subtidal regions along the south part of Japan. Cladosiphon umezakii is distinguished by long assimilatory filaments up to 840 μm from the other taxa of the genus (Ajisaka et al. 2007). It is most similar with C. filum (Harvey) Kylin from Australia having long assimilatory filaments up to 800 μm, however it differs from C. umezakii on the basis of its habitus (mainly epiphytic) and cell number of assimilatory filaments (Womersley 1987; Ajisaka et al. 2007). In this study, we encountered Cladosiphon umezakii on the southern coast of Korea. Both morphological characters and plastid rbcL regions of the species confirmed its identity. Two slimy chordariacean species, Tinocladia crassa (Suringar) Kylin and Papenfussiella kuromo (Yendo) Inagaki in Korea were also included for comparison.

Ceramium kondoi is a morphologically variable ceramiaceous red alga that occurs commonly in the northwest Pacific Ocean region and has recently been reported in the United States. Forty-five specimens of C. kondoi from 29 locations in Korea, Japan, Russia, and the USA were examined for DNA sequence variation along the whole plastid-encoded RuBisCO cistron: 1406 bp for rbcL, 103 bp for the spacer, and 387 bp for rbcS. C. kondoi specimens were variable, having up to nine haplotypes, with six found in Korea, southern Japan, far-eastern Russia, and the USA, and three found in northern Japan and far-eastern Russia. The occurrence of the same haplotype on both sides of the North Pacific Ocean provides evidence of recent introduction of the species from the west to the east. Phylogenetic reconstructions revealed the monophyly of C. kondoi and two well-supported lineages: a ‘southern lineage’ that contained specimens from Korea, southern Japan, far-eastern Russia and the USA, and a ‘northern lineage’ that included specimens from northern Japan and far-eastern Russia. The two genetic lineages are morphologically indistinguishable and referred to as cryptic species. The boundary between the two cryptic species is at the Tsugaru Strait, Japan.

A new genus, Pseudolessonia, is proposed for the kelp Lessonia laminarioides Postels et Ruprecht (Laminariales, Phaeophyceae), which occurs on the northwest side of the Sea of Okhotsk, in the northwest Pacific Ocean. Pseudolessonia is monotypic and differs from Lessonia in its short primary stipes and its corrugated, unilaterally arranged blades with entire margins. This species is transferred on the basis of morphology and plastid gene sequence comparisons. We determined psaA and rbcL gene sequences from 17 taxa of Pseudolessonia, Lessonia, and putative relatives. Analyses of individual and combined data sets resulted in con gruent trees showing a clear separation of Pseudolessonia laminarioides from Lessonia, but suggesting its sister relationships with the clade of Nereocystis, Macrocystis, Pelagophycus, and Postelsia in the North Pacific Ocean. On the other hand, Lessonia species from the South Pacific Ocean formed a strongly supported clade. The results indicate that the basal splitting of the blade, which has been considered a diagnostic character for the family Lessoniaceae, is a result of convergent evolution.

A terrestrial chlorophyte, Chlorococcum sp., was isolated from the stone walls of Miruksazi stupa, which is a national treasure of Korea. The alga was one of the dominant organisms contributing to biodeterioration of the monument and it grew extensively on the walls of the inner room of the stupa, which had been sealed for more than 5 yr before we started this experiment. Chlorococcum survived in darkness during that time as dormant, warty, thick-walled spores. The resting spores revived in freshwater medium and released numerous unicellular progeny, which were isolated into a unialgal culture. The isolate was subjected to 18S rDNA phylogenetic analysis as well as ultrastructure and life cycle studies. In addition, the effect of salinity stress was investigated using sterile enriched seawater as a medium. Chlorococcum sp. grew in seawater culture medium for more than 5 mo and reproduced by aplanospores.

Soranthera Postels et Ruprecht is a monospecific brown algal genus with S. ulvoidea Postels et Ruprecht (Postels and Ruprecht 1840; Setchell and Gardner 1925; Bold and Wynne 1985), which was described based on specimens from Sitka, Alaska, USA (Postels and Ruprecht 1840). S. ulvoidea is annual and occurs exclusively in Kamchatka, the Bering Sea, Aleutian Islands, Alaska, to Baja California (Wynne 1969; Hansen 1997; Klochkova 1998; Mondragon and Mondragon 2003). Thalli are globose, hollow, and epiphytic on Neorhodomela and Odonthalia in the mid to low intertidal (Setchell and Gardner 1925; Angst 1926, 1927; Mondragon and Mondragon 2003). The sacs of S. ulvoidea are the sporophyte stage that produces swimming spores with flagella. This phase alternates with a microscopic, filamentous gametophyte that produces gametes (Angst 1926; Wynne 1969). S. ulvoidea is divided into two forms; f. ulvoidea is oval to spherical in shape and has thick membrane and f. difformis is deeply lobed and has thin membrane (Setchell and Gardner 1925). S. ulvoidea is very similar to other saccate or globose brown algal epiphytes like Colpomenia. On establishing the genus Soranthera, the familial position of the genus remained unclear (Postels and Ruprecht 1840). Kjellman (1893 in 1891-1896) placed Soranthera and Asperococcus in the Asperococcaceae of the Encoeliaceae. Setchell and Gardner (1925) put the genus in the Asperococcaceae of the Ectocarpales, despite the establishment of the Dictyosiphonales. Since Papenfuss (1947) extended the Dictyosiphonales to include the Punctariales and treated the Asperococcaceae as a synonym of the Punctariaceae (Papenfuss 1955), Soranthera, together with Punctaria, has been placed in the Punctariaceae of the Dictyosiphonales (Wynne 1969; Bold and Wynne 1985). However, Pedersen (1984) doubted the taxonomic position of the genus in the Punctariaceae. Based on DNA phylogeny, plastid structure, and life histories, the order Ectocarpales consists of five families, viz. Acinetosporaceae, Adenocystaceae, Chordariaceae, Ectocarpaceae, and Scytosiphonaceae (Peters and Ramirez 2001). In this revision, the Chordariaceae Algae Volume 20(2): 91-97, 2005

Colpomenia peregrina shows a large morphological variation, and two morphotypes have been described. We used the protein-coding plastid rbcL and the nuclear ribosomal internal transcribed spacer (ITS) region to investigate whether these morphotypes constitute distinct species and to explain the current distribution of the species. Here, we sequenced the rbcL gene from 38 specimens (32 C. peregrina and six putative relatives) and the ITS region from 33 specimens of C. peregrina, including an outgroup taxon. The C. peregrina specimens were variable, having up to 1.17% intraspecific divergence and nine haplotypes in the rbcL gene, and up to 11.01% intraspecific divergence and 21 haplotypes in the ITS region. Independent analyses of the rbcL and ITS data sets produced highly congruent but not identical results. Colpomenia peregrina is monophyletic, but is partitioned into two deeply divergent clades (‘lineage I’ and ‘lineage II’) that we interpret as different species. Lineage I consists of 27 specim...

The brown algal family Ishigeaceae currently includes a single genus, Ishige Yendo, with two species. The relationship of the family to other brown algal lineages is less studied in terms of their plastid ultrastructure and molecular phylogeny. We determined the sequences of rbcL from four samples of the two Ishige species and nine putative relatives and the psaA and psbA sequences from 37 representatives of the brown algae. Analyses of individual and combined data sets resulted in similar trees; however, the concatenated data gave greater resolution and clade support than each individual gene. In all the phylogenies, the Phaeophyceae was well resolved, the Ectocarpales being placed in a terminal position and the Ishigeaceae ending up in a basal position. From our ultrastructural study, we concluded that the pyrenoid is absent in the Ishigeaceae, despite the presence of a rudimentary pyrenoid in I. okamurae. These results suggest that the Ishigeaceae is an early diverging brown lineage. Our molecular and morphological data, therefore, lead us to exclude the Ishigeaceae from the Ectocarpales s.l., which have an elaborate pyrenoid, and to propose its own order Ishigeales ord. nov. The Ishigeales is distinguished by oligostichous structure of thalli, phaeophycean hairs formed within cryptostomata, unilocular sporangia transformed from terminal cortical cells, and plurilocular sporangia lacking sterile terminal cells. This study is the first to document the utility of the psaA and psbA sequences for brown algae and also the first report on the multigene phylogeny of the Phaeophyceae based on three protein-coding plastid genes.

Scytosiphonaceae is an acetocarpalean brown algal family, that is a recent focus of synstematics and marine biodiversity. We describe Petalonia zosterifolia and Scytosiphon gracilis from Korea for the first time. P. zosterifolia occurred on the East coast, and had flat, linear and solid thalli. S. gracilis was found in Jeju, and had cylindircal to flat and hol-low thalli. However, these two species are so similar that it is difficult to identify by morphology alone. In order to determine if the nuclear DNA reveals the distinctness of both species and to know their phylogenies, the ITS region sequences were newly detrmined in 22 samples of P. zosterifolia, Scytosiphon gracilis, and other three members of the genera from Korea. We found 0.12% variation among samples of P. zosterifolia from different locations, and no variation between S. gracilis samples from diferent years, but extensive interspecific divergences (13.62-22.83%) of each species to other members in Petalonia and Scytosiphon . The ITS sequence dta consistently showed a close relationship between P. zosterifolia and S. gracilis. This result is congruent with morphology and with the published data of plastid rbc and partial nrDNA large subunit gene sequences, and suggests that P. zosterifolia and S. gracilis might have diverged from the most recent common ancestor.

In this work we report the occurrence of Scytosiphon gracilis Kogame (Scytosiphonaceae, Phaeophyceae) on the Pacific coast of Mexico. This is the first report of S. gracilis outside its previously known distribution in the western North Pacific (Korea and Japan). The identification was based on a morphological revision and a comparison of the plastid-encoded RuBisCO spacer sequences determined for Korean and Mexican algal material. Thalli were collected from the intertidal zone of Saldamando Beach, Baja California, in January 2003. The vegetative structure, as well as habitat and geographic distribution of the species are described. Reproductive structures were not found in our specimens. The poor presence/absence of S. gracilis in previous floristic studies of the area could be due to its small size and low frequency.

Colpomenia, a small genus with 11 species of globular to bullate form, occurs in temperate to tropical waters worldwide. Because morphology is highly diverse, the specieslevel taxonomy requires re-evaluation. We analyzed the mitochondrial cox3 gene from 50 samples of the genus. A new species, Colpomenia claytonii sp. nov., is described based on samples collected from Korea, Japan, Hong Kong, Australia, New Zealand, South Africa, and the USA and compared with similar congeners. Compared to others, the new species is larger, and has a more irregular thallus often with a deeply infolded surface. It is usually epilithic in tide pools and in the lower intertidal and subtidal zones. In all phylogenetic analyses of cox3 sequences, C. claytonii was consistently distinct from congeners. Colpomenia expansa is closely related to C. claytonii, and the clade containing these two species is closely related to C. peregrina. A total of 14 cox3 haplotypes was found in C. claytonii, indicating high haplotype diversity and a recent dispersal pattern. The present study shows that C. claytonii is a widely distributed species across the Pacific Ocean to South Africa; it was previously misidentified as a variant of C. peregrina.

Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related. These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. Brown algae are also one of only a small number of eukaryotic lineages that have evolved complex multicellularity (Fig. 1). We report the 214 million base pair (Mbp) genome sequence of the filamentous seaweed Ectocarpus siliculosus (Dillwyn) Lyngbye, a model organism for brown algae, closely related to the kelps (Fig. 1). Genome features such as the presence of an extended set of light-harvesting and pigment biosynthesis genes and new metabolic processes such as halide metabolism help explain the ability of this organism to cope with the highly variable tidal environment. The evolution of multicellularity in this lineage is correlated with the presence of a rich array of signal transduction genes. Of particular interest is the presence of a family of receptor kinases, as the independent evolution of related molecules has been linked with the emergence of multicellularity in both the animal and green plant lineages. The Ectocarpus genome sequence represents an important step towards developing this organism as a model species, providing the possibility to combine genomic and genetic approaches to explore these and other aspects of brown algal biology further. © 2010 Macmillan Publishers Limited. All rights reserved.

International audience; Ectocarpus siliculosus has been proposed as a genetic and genomic model for the brown algae and the 214 Mbp genome of this organism has been sequenced. The aim of this project was to obtain a chromosome-scale view of the genome by constructing a genetic map using microsatellite markers that were designed based on the sequence supercontigs. To map genetic markers, a segregating F 2 population was generated from a cross between the sequenced strain (Ec 32) and a compatible strain from northern Chile. Amplified fragment length polymorphism (AFLP) analysis indicated a significant degree of polymorphism (41%) between the genomes of these two parental strains. Of 1,152 microsatellite markers that were selected for analysis based on their location on long supercontigs, their potential as markers and their predicted ability to amplify a single genomic locus, 407 were found to be polymorphic. A genetic map was constructed using 406 markers, resulting in 34 linkage groups. The 406 markers anchor 325 of the longest supercontigs on to the map, representing 70.1% of the genome sequence. The Ectocarpus genetic map described here not only provides a large-scale assembly of the genome sequence, but also represents an important tool for future genetic analysis using this organism.

Previously unrecorded marine Chlamydomonas that grew epiphytic on ceramiaceaen algae was collected from the western coast of Korea and isolated into a unialgal culture. The isolate was subjected to 18S rDNA phylogenetic analysis as well as ultrastructure and life cycle studies. It had an affinity with the marine Chlamydomonas species and was less related to freshwater/terrestrial representatives of this genus. It had flagella shorter than the cell body two-layered cell wall with striated outer surface and abundant mucilaginous material beneath the innermost layer and no contractile vacuoles. This alga grew faster in mixed cultures with ceramiaceaen algae rather than in any tested unialgal culture condition; the cells looked healthier and zoosporangia and motile flagellated vegetative cells appeared more often. These results suggested that this Chlamydomonas might be a facultative epiphyte benefiting from its hosts. Several ceramiaceaen algae were tested as host plants. Meanwhile, cell deformation or collapse of the whole thallus was caused to Aglaothamnion byssoides, and preliminary study suggested that a substance released from Chlamydomonas caused the response. This is first report on harmful epiphytic interactions between Chlamydomonas species and red ceramiaceaen algae.

Fucalean brown algae are ecologically important for maintaining intertidal to subtidal ecosystems and are currently a subject for DNA phylogenies. We analyzed the photosystem I coding psaA gene (1488 base pairs) from 26 taxa in all families of the Fucales including Nemoderma tingitanum and Microzonia velutina as outgroup species. A total of 41 taxa, including published sequences from three fucalean and 13 brown algae, were used for phylogenetic analyses. The psaA phylogenies confirmed previous ideas, based on previous studies using morphology and nuclear ribosomal genes, suggesting that the fucalean algae are monophyletic, including the Durvillaeaceae and Notheiaceae. However, in all analyses of the psaA data, the Notheiaceae, endemic to Australasia, occupied a basal position within the order. All families except the Cystoseiraceae are monophyletic. The psaA data together with previous nuclear ribosomal DNA data and autapomorphic morphological characters strongly support that the genera Bifurcari...

The identification of two Atlantic kelp species, Laminaria longicruris and L. saccharina, has been controversial. In order to know if these two species are conspecific, plastid-encoded RuBisCo spacer and nuclear rDNA ITS sequences were analyzed from twelve individuals of L. longicruris, five of L. saccharina, from Connecticut and Nova Scotia. Four individuals of L. digitata from the above coasts were also analyzed as reference in this study. All RuBisCo spacer sequences from L. longicruris and L. saccharina were exactly identical except for one individual with three different nucleotides. Zero to five different nucleotides of ITS sequences, inculding four polymorphic sites, were found in two species. However, their RuBisCo spacer and ITS sequences are quite different from those of L. digitata. These results strongly suggest that L. saccharina (L.) Lamour. 1813 is conspecific with L. longicruris De La Pylaie 1824 and the different local populations, despite various morphotypes, may be genetically very similar.

Alaria is a common kelp genus generally found in the lower intertidal and shallow subtidal regions of rocky shores in the cold waters of the northern Hemisphere. About 16 species are currently recognized worldwide and, of these, A. fistulosa is distinguished by having hollow midrib and large blades with 10–30 m in length and 30–90 cm in width. It is the only canopy-producing kelp in the northwest Pacific, where it is restricted to the waters of north Hokkaido, Kamchatka, Aleutian Islands, and Alaska. In order to know the phylogenetic position of A. fistulosa, sequences of nr DNA ITS and plastid rbcL including spacer and psaA regions were determined in A. fistulosa and compared with homologous positions of newly sequenced putative relatives and with published sequences of other kelp species. Combined data of ITS and Rubisco spacer show that A. fistulosa was more related to the clade of Lessoniopsis and Pterygophora than to the clade of other species of Alaria, which is supported by the rbcL and psaA sequence data. The topologies from nuclear and plastid DNA sequences lead to phylogenetic independence of A. fistulosa, which is clearly different from the genus Alaria.