Erect Thalli Research Articles

Sporochnus keyari sp. nov. (Sporochnales, Phaeophyceae) from Japan

ABSTRACT In the genus Sporochnus (Sporochnales, Phaeophyceae), Okamura reported S. radiciformis and S. scoparius in Japan in 1922; however, S. scoparius was later synonymized with S. radiciformis, as Okamura’s S. radiciformis was considered to be a young stage of S. scoparius. Therefore, only one species, S. radiciformis, has been recognized in Japan, until the reported occurrence of a second species, S. dotyi, and suggestion that the species identified as S. radiciformis in Japan was genetically distinct from true S. radiciformis described from Australia. We now report findings that based on molecular phylogeny (atpB, rbcL, atp6, cox3) and morpho-anatomical analyses confirming that the common Japanese Sporochnus species is distinct from true S. radiciformis, and we therefore describe a new species, S. keyari sp. nov. This new species differs from S. radiciformis in having less-branched erect thalli, longer terminal assimilatory filaments (trichothallic hairs), and larger unilocular zooidangia, and from S. bolleanus in having more robust thallus axes. In gross morphology, S. keyari is distinguished from S. dotyi, which is also distributed in Japan, in having more slender thalli and lacking greenish structural colour of the assimilatory filaments. In culture, unizoids (zoospores) released from unilocular zooidangia developed into monoicous gametophytes forming antheridia and oogonia at the distal ends of the filaments. Actual sexual fusion was not observed, but presumably fertilization occurred within oogonia and new sporophytes developed in situ within oogonia. Sporophytes were at first uniseriate, but later formed terete thalli by trichothallic growth, with terminal assimilatory filaments.

Two new species of Dictyota (Dictyotales, Phaeophyceae), D. dimorphosa sp. nov. and D. recumbens sp. nov., based on morphological and molecular investigations

ABSTRACT The brown algal genus Dictyota (Dictyotales, Phaeophyceae) is widespread, particularly in warm temperate and tropical waters, and plays a vital role in coastal ecosystems. This study reassessed the taxonomy of Dictyota, focusing on specimens from Myanmar and Japan, using a combination of morphological and molecular analyses. Molecular phylogenetic analyses using concatenated DNA sequences of rbcL, psaA, psbA, cox1 and cox3 genes revealed that Dictyota specimens from Myanmar, Japan, and other regions, belong to nine different clades, each representing a different species. Based on morphological and molecular data, seven out of these nine clades are identified as known species, while the remaining two clades are described as new species D. recumbens sp. nov. (=D. sp. A) and D. dimorphosa sp. nov. (=D. sp. B). Dictyota recumbens is characterized by the recumbent thallus, with transverse yellowish-green iridescent lines, and the formation of solitary spores irregularly distributed over the thallus. Dictyota dimorphosa is characterized by two morphological forms: decumbent and erect thalli, with bluish iridescence mainly in the decumbent thallus, and the formation of spores in oval ring shapes distributed over both thallus surfaces. Dictyota recumbens was typically found in tropical regions, while D. dimorphosa appears to be a cool-warm temperate species, distributed from northeastern Hokkaido to southern Kyushu with an extension along South Korea. Our molecular phylogenetic analyses have revealed the existence of several species whose names appeared in multiple clades, suggesting the potential for future increases in species diversity and the presence of cryptic species within certain groups.

New record of Sporochnus dotyi (Sporochnales, Phaeophyceae) from Kii Peninsula, Japan

SUMMARYThe subtidal brown algal species Sporochnus dotyi Brostoff (Sporochnales, Phaeophyceae), which has been regarded as a Hawaiian endemic, is reported from Kushimoto, Kii Peninsula, Pacific coast of central Honshu, Japan, for the first time outside Hawai'i. The species grew on subtidal rocks ca. 5–20 m deep attached by a small conical holdfast. The erect thalli were 5–30 cm high, terete, robust and alternately branched in 1–2 orders. When mature, pedicellate receptacles developed on the branches, and formed elliptical sori 1 mm long with a pedicel 3–5 mm long. The apical parts of the thalli and the receptacles were terminated with a tuft of simple assimilatory filaments of up to 4 mm long and showed prominent green to yellow underwater iridescence. Reproductive filaments (paraphyses) were densely packed, simple, up to 200 μm long and bore 4–6 mostly unilateral unilocular zoidangia 20–22 μm long and 5–6 m in diameter. In the genetic analyses, the Sporochnus alga from Kushimoto had partial rbcL sequence identical to S. dotyi from Hawai'i. The cox3 phylogeny revealed that this alga formed a fully supported clade with S. dotyi. Therefore, we identified the alga from Kushimoto as S. dotyi. This finding of S. dotyi from Japan, together with the recent reports of the mesophotic macroalgae Ryuguphycus kuaweuweu (=Umbraulva kuaweuweu), Ulva iliohaha and Newhousia imbricata from various localities in the Pacific Ocean including Japan, suggest closer biogeographical connections of subtidal/mesophotic macroalgae in the Pacific than previously recognized.

Kuwaitiella rubra gen. et sp. nov. (Bangiales, Rhodophyta), a new filamentous genus and species from the north‐western Indian Ocean

SUMMARYA new filamentous marine red alga, Kuwaitiella rubra gen. et sp. nov. (Bangiales, Rhodophyta), is described from Kuwait in the north‐western Arabian Gulf (also referred to as the Persian Gulf). It was found on a submerged fishing line. The intensively red upright thallus of up to 1 cm in length consists of cells containing a single stellate plastid. The thallus is initially uniseriate but becomes biseriate in its distal part upon transformation into globular reproductive cells, possibly archaeospores. The biseriate fertile part is the only morphological difference from other filamentous species of the Bangiales, in which this region is parenchymatous. In culture, bipolar asymmetric germination of the spores of Kuwaitiella led to a new generation of identical erect thalli, fixed to the substratum by colourless rhizoids. According to phylogenetic analyses of partial small subunit nuclear ribosomal DNA (18S) and of the plastid‐encoded ribulose‐1,5‐bisphosphate carboxylase/oxygenase large subunit (rbcL), the new species forms an additional lineage of the Bangiales, genetic similarity with other taxa being limited (maximum 91% in SSU and 90% in rbcL). It was no clear member of any known lineage of the Bangiales but was weakly associated with the filamentous species Minerva and Dione from New Zealand. In a SSU phylogeny, it formed a basal branch in the Bangiales and clustered with M. aenigmata and D. arcuata as sister clade to all other species of the order. In a rbcL phylogeny, it was part of a large polytomy of lineages, its closest relative being D. arcuata. Kuwaitiella forms the 8th lineage of filamentous Bangiales detected so far.

Discovery of a novel brown algal genus and species Setoutiphycus delamareoides (Phaeophyceae, Ectocarpales) from the Seto Inland Sea, Japan

We describe a new genus and species of brown algae from the Seto Inland Sea, Japan. This species is similar to Delamarea in gross morphology and anatomy, but distinctive in having longer thalli with rare branching and shorter cortical cells. In culture, pluri-zoids derived from plurilocular zoidangia on the erect thalli developed into filamentous gametophytes bearing ectocarpoid plurilocular zoidangia, but also formed parenchymatous erect thalli of sub-sympodial growth similar to Trachynema often having branches, and formed lateral and terminal plurilocular zoidangia. Molecular phylogenies using concatenated chloroplast and mitochondrial gene sequences showed the new alga nested in the clade composed of ectocarpalean genera with diffuse growth, parenchymatous thalli, and multiple chloroplasts, but this species is distinctive. Therefore, we propose Setoutiphycus delamareoides gen. & sp. nov. for this new alga, and provisionally place it in Chordariaceae, Ectocarpales. The Seto Inland Sea repeatedly dried during sea level regressions during glacial periods, and the present sea level recovered after the last glacial maximums (LGM), ca. 10,000 years ago. Therefore, it is unlikely that the species evolved within this area. Its distribution in the area may be explained as a remnant population that survived in refugia in southern Japan during the LGM.

Taxonomic revision of Saundersella (Ectocarpales s.l., Phaeophyceae) from the northwestern Pacific with description of Saundersella crassa sp. nov. and transfer of Heterosaundersella hattoriana to Saundersella

ABSTRACT Saundersella crassa sp. nov. (Ectocarpales s.l., Phaeophyceae) is newly described from cold-water regions of Japan and the northern Pacific. Saundersella crassa is similar to S. simplex (generitype) in morphology and has been identified as S. simplex in the area, but it has longer and thicker thalli, grows on different basiphytes (S. crassa on Chordaria spp vs S. simplex on Analipus spp) and is genetically distinct in the mitochondrial cox3 and chloroplast atpB, psaA, psbA and rbcL DNA sequences. The erect thalli of S. crassa were simple, filiform, soft and gelatinous, solid when young but later becoming hollow, cord-shaped, attenuated at the base to an indistinct stipe, at times twisted, yellowish to olive brown, and up to 50(–90) cm long and 5 mm wide. The erect thalli were composed of multiaxial colourless central medullary filaments and pigmented assimilatory filaments of 2–6 cells. Terminal cells of the assimilatory filaments were large and swollen, spherical or obovate. Unilocular zoidangia were sessile and obovate or irregular in shape, and were formed on erect thalli at the end of medullary cells or at the base of assimilatory filaments. In the molecular phylogeny, the type of the genus Heterosaundersella, H. hattoriana, was sister to S. crassa and was nested in the clade composed of S. simplex and S. crassa, irrespective of their differences in the habit and occurrence of basal prostrate thalli forming plurilocular zoidangia. Therefore, we propose the new combination S. hattoriana comb. nov. for H. hattoriana. Heterosaundersella thus becomes a taxonomic synonym of Saundersella.

Morphology of filamentous thalli of Analipus japonicus (Ralfsiales), temperature and irradiance effects on their formation and growth, and erect thallus formation in the field

Free-living filamentous thalli derived from an Analipus japonicus erect thallus were established in laboratory culture. The filamentous thalli were composed of slender filaments and densely pigmented oval or sub-oval cell masses. Temperature (5–20 °C) and irradiance (25–200 μmol photons m−2 s−1) effects on formation and growth of the thalli from three explant groups (isolated filaments, small cell masses, and large cell masses) were investigated for 15 days. These explants survived over the examined range. The isolated filaments had a high ability to form the thalli, and the isolated and new filaments formed filaments and cell masses. Meanwhile, the isolated and new cell masses formed only filaments, and their ability to grow and form the thalli decreased as they grew in size. Optimum culture conditions for formation and growth of the thalli from the isolated filaments, and the two cell mass growths were 15–20 °C and 100–200 μmol photons m−2 s−1. To produce erect thalli, the filamentous thalli were cultured on seedling threads for 6 weeks at 15 °C, 60 μmol photons m−2 s−1 and 20 cm s−1 water flow velocity. Erect axis density increased with increasing coverage of the filamentous thalli, and their cell masses (primordia of erect thallus holdfast) with mean area of about 140 × 103 μm2 began to produce erect axes. After 4 months of field cultivation, they grew into full-grown erect thalli of about 20 cm long. These findings show that the free-living filamentous thalli were applicable for stable seedling production of A. japonicus to be used in aquaculture.

Species delimitation of Planosiphon gracilis morphospecies (Scytosiphonaceae, Phaeophyceae) from Japan and the description of Pl. nakamurae sp. nov.

ABSTRACTMolecular phylogenetic analyses based on mitochondrial cox1 and cox3 and chloroplast rbcL gene sequences revealed that the morphospecies of the brown alga Planosiphon gracilis (Scytosiphonaceae, Ectocarpales) from Japan is a complex of three distinct lineages (lineages I–III). Specimens from these lineages had the typical morphology of Pl. gracilis (i.e. flattened, linear, hollow, and gregarious erect thalli); thus, morphological discrimination among them was difficult in many cases. We observed large genetic divergences among the three lineages (c. 10% in cox1 and cox3). Moreover, we observed a reproductive isolating barrier between lineages I and II, despite the wide overlap in their geographic distribution. Our data, therefore, suggest that these three lineages are distinct species. Since lineage I included the holotype specimen of Pl. gracilis, this lineage was attributed to Pl. gracilis. Lineage III was phylogenetically close to Pl. complanatus from Canada with a 4.1% divergence in cox1. For lineage II, a new species name, Pl. nakamurae sp. nov., was proposed. This new species was also found in Argentina.

Dictyota falklandica sp. nov. (Dictyotales, Phaeophyceae) from the Falkland Islands and southernmost South America

ABSTRACTSurveys of the seaweed flora of the Falkland Islands and of Tierra del Fuego revealed the presence of a new species of brown alga. Dictyota falklandica sp. nov. inhabits the shallow rocky infralittoral in sheltered localities and the lower intertidal in more exposed sites. Dictyota falklandica has a regular to irregular habit of dichotomously branched blades, forming erect thalli composed of a single-layered cortex and medulla, with margins in the apical parts dotted with dormant apical cells. Sporangia occur in irregular groups or longitudinal lines on the thallus surface. Molecular phylogenies based on chloroplast psbA and rbcL and mitochondrial cox1 sequences showed that the species from the Falkland Islands is sister to a clade formed by D. korowai, recently described from New Zealand and D. kunthii known from both the Pacific coast of South America and New Zealand. Temperature tolerance experiments, showing mortality at 25 °C but survival at 20 °C, confirm the cold-temperate affinity of this taxon. Its relationship to other cold-temperate Southern Hemisphere species is discussed, with its closest relatives living in regions with sea surface temperatures of at least 7–10 °C higher.

Taxonomic study of the brown algal genus Chorda (Chordaceae, Laminariales) with description of the new species Chorda borealis from Alaska and northern Canada

ABSTRACT Chorda borealis sp. nov. is newly described from Alaska and northern Canada. Chorda borealis resembles C. filum and C. asiatica in gross morphology, but has a thinner cortical layer than those two taxa and is genetically distinct in the mitochondrial cox1 and cox3, plastid atpB, psbA and rbcL, and nuclear rDNA ITS1-5.8S-ITS2 region DNA sequences. The erect thalli are simple, cord-shaped, medium to light brown, and up to 90 cm in length and 2 mm in diameter. The mid-thallus cortex is composed of 2–4 cells and is 110–230 µm thick. When mature, unilocular zoidangia develop among unicellular clavate paraphyses and measure 30–48 µm long and 8–13 µm in diameter, containing presumably 16 zooids, each with an eyespot. The distributional pattern of C. borealis, which is distributed from the northern Pacific Ocean to the Labrador Sea and connected to the north-western Atlantic through the Arctic, suggests that the dispersal of Chorda species from the Pacific to the Atlantic could have occurred along the coasts of the north-western Arctic Sea.

Tinocladia sanrikuensis sp. nov. (Ectocarpales s.l., Phaeophyceae) from Japan

SUMMARYThe new species Tinocladia sanrikuensis sp. nov. H.Kawai, K.Takeuchi & T.Hanyuda (Ectocarpales s.l., Phaeophyceae) is described from the Pacific coast of the Tohoku region, northern Japan based on morphology and DNA sequences. The species is a spring–summer annual growing on lower intertidal to upper subtidal rocks and cobbles on relatively protected sites. T. sanrikuensis has a slimy, cylindrical, multiaxial erect thallus, slightly hollow when fully developed, branching once to twice, and resembles T. crassa in gross morphology. The erect thalli are composed of a dense medullary layer, long subcortical filaments, and assimilatory filaments of 11–35 cells, up to 425 μm long and curved in the upper portion. Unilocular zoidangia are formed on the basal part of assimilatory filaments. The species is genetically most closely related to T. crassa and has the same basic thallus structures but differs in having thinner and longer assimilatory filaments. DNA sequences of the mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes support the distinctness of this species.

Proposal of a new brown algal species, Mesogloia japonica sp. nov. (Chordariaceae, Phaeophyceae), and transfer of Sauvageaugloia ikomae to Mesogloia

ABSTRACTA molecular phylogeny using mitochondrial cox1 and cox3 and chloroplast atpB, psaA, psbA and rbcL gene sequences revealed that the Japanese endemic brown alga Sauvageaugloia ikomae (Ectocarpales s.l.) is phylogenetically distant from the generitype S. divaricata described from Europe. It also suggests the occurrence of an undescribed species in the Seto Inland Sea and the Pacific coast of the Tohoku Region; whereas, S. ikomae is distributed in the Sea of Japan. The new species is genetically distinct from S. ikomae and is morphologically distinguishable in having thicker erect thalli with a more developed subcortical layer. In the phylogeny, the clade of Japanese Sauvageaugloia was sister to Mesogloia, both nesting in the clade of Cladosiphon species. Because ectocarpalean taxa are considered to be oversplit at generic rank compared to genetic divergence within the order, we refrain from describing a new genus for S. ikomae and the new species and instead suggest placing them in Mesogloia. We therefore propose the establishment of the new species Mesogloia japonica and a new combination M. ikomae. We also propose including Liebmannia leveillei in the genetically indistinguishable Mesogloia vermiculata.

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 & Rodríguez-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.

The establishment of the non-native seaweed Polysiphonia morrowii in Northern Patagonia: Size of thallus and reproduction

A population of Polysiphonia morrowii, recently introduced in the South West Atlantic Ocean, was studied to determine the degree of its establishment. Monthly variations of: thallus size, proportion of life history phases, and tetrasporangia production, were evaluated from June to October 2010. The erect thalli appeared in autumn, and decayed in spring when they became overgrown by epiphytic diatoms. Vegetative thalli were usually smaller than fertile thalli. In spring, the thalli had the maximum mean values of length (199.5mm), thickness (52mm) and dried weight (4g). Although tetrasporophytes represented between 73% and 90% of the thalli collected each month, a few cystocarpic thalli were also found. Variations of thallus size and proportion of life history phases were also studied between 2010 and 2014. The inter-annual increase in the proportion of the tetrasporophytic phase and the progressive increase of the size of P. morrowii thalli indicated an ongoing establishment of the population in this habitat.

Cladosiphon takenoensis sp. nov. (Ectocarpales s.l., Phaeophyceae) from Japan

SUMMARYThe new brown algal species Cladosiphon takenoensis H. Kawai (Chordariaceae, Ectocarpales s.l.) is described from Takeno, Hyogo, Japan based on morphology and DNA sequences. The species is a spring annual, growing on subtidal rocks at more or less exposed sites. It resembles C. umezakii in its gross morphology, and the two often grow together, but is distinguishable from C. umezakii in having a more hairy appearance. Cladosiphon takenoensis has a slimy, cylindrical, multiaxial and sympodial erect thallus, branching once to twice, and is provided with long assimilatory filaments (up to 1.8 mm long, composed of up to 100 cells). Unilocular zoidangia are formed on the basal part of assimilatory filaments. The species is genetically most related to C. umezakii and has the same basic thallus structures, but differs from C. umezakii and other Cladosiphon species in lacking phaeophycean hairs and plurilocular zoidangia of the assimilatory filaments. DNA sequences of the mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes and the nuclear rDNA ITS2 region support the distinctness of the species. The genus Cladosiphon was paraphyletic in our analyses because the clades of C. okamuranus/C. zosterae and C. takenoensis/C. umezakii were split by Mesogloia vermiculata. However, since the genus‐level taxonomy of Chordariaceae needs considerable revision, we suspend the genus‐level taxonomy of the new species, and tentatively describe it as C. takenoensis.

Dictyota chalchicueyecanensis sp. nov. (Dictyotales, Phaeophyceae) en el Golfo de México: evidencias moleculares y morfológicas

Background. Species of the Dictyota genus have a high phenotypic plasticity that contrasts with their limited morphological diagnostic characteristics, which has led to some uncertainty in identifying species in the Gulf of Mexico. Recent studies worldwide have focused on Dictyota species phylogenies, which are the basis for contrasting and interpreting the results of this study. Goals. In our research, we found evidence of a new species belonging to the Dictyota genus in three localities in the state of Veracruz, Mexico (Playa Hermosa, Punta Puntillas y Villa Rica). Methods. Phylogenetic and molecular analyses of partial sequences of the psbA and cox1 genes were performed, complemented by morphological analysis. Results. In phylogenetic analysis of partial sequences of psbA and cox1, we established that samples of the new species form a well-supported monophyletic clade. In addition, the genetic divergence values that were obtained are within the interspecific values for the genus, allowing us to segregate the Dictyota chalchicueyecanensis sp. nov. from the rest of the species of this genus. Morphologically this new species is characterized by an erect thallus, light brown and lacking iridescence, stiff to the touch, with a discoid holdfast, rounded apices, dichotomous branching, dentated margins, with minute teeth, triangular to spinose in shape that are directed toward the apices. Sporangia are isolated or grouped on both sides of the thallus and germinate regularly in interdichotomous basal portions. Conclusion. These results allow us to expand the diversity of the genus Dictyota worldwide, incorporating D. chalchicueyecanensis as a probable new species endemic to Mexico.

Molecular phylogeny of two unusual brown algae, Phaeostrophion irregulare and Platysiphon glacialis, proposal of the Stschapoviales ord. nov. and Platysiphonaceae fam. nov., and a re-examination of divergence times for brown algal orders.

The molecular phylogeny of brown algae was examined using concatenated DNA sequences of seven chloroplast and mitochondrial genes (atpB, psaA, psaB, psbA, psbC, rbcL, and cox1). The study was carried out mostly from unialgal cultures; we included Phaeostrophion irregulare and Platysiphon glacialis because their ordinal taxonomic positions were unclear. Overall, the molecular phylogeny agreed with previously published studies, however, Platysiphon clustered with Halosiphon and Stschapovia and was paraphyletic with the Tilopteridales. Platysiphon resembled Stschapovia in showing remarkable morphological changes between young and mature thalli. Platysiphon, Halosiphon and Stschapovia also shared parenchymatous, terete, erect thalli with assimilatory filaments in whorls or on the distal end. Based on these results, we proposed a new order Stschapoviales and a new family Platysiphonaceae. We proposed to include Phaeostrophion in the Sphacelariales, and we emended the order to include this foliose member. Finally, using basal taxa not included in earlier studies, the origin and divergence times for brown algae were re‐investigated. Results showed that the Phaeophyceae branched from Schizocladiophyceae ~260 Ma during the Permian Period. The early diverging brown algae had isomorphic life histories, whereas the derived taxa with heteromorphic life histories evolved 155–110 Ma when they branched from the basal taxa. Based on these results, we propose that the development of heteromorphic life histories and their success in the temperate and cold‐water regions was induced by the development of the remarkable seasonality caused by the breakup of Pangaea. Most brown algal orders had diverged by roughly 60 Ma, around the last mass extinction event during the Cretaceous Period, and therefore a drastic climate change might have triggered the divergence of brown algae.

Species delimitation of the genus Champia (Rhodymeniales, Rhodophyta) from Korea using DNA barcoding

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 filaments 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.

Morphological and molecular evidence support the recognition of Champia lubrica sp. nov. (Champiaceae, Rhodophyta) from Japan

Suzuki M., Hashimoto T., Kitayama T. and Nozaki H. 0000. Morphological and molecular evidence support the recognition of Champia lubrica sp. nov. (Champiaceae, Rhodophyta) from Japan. Phycologia 52: 609–617. DOI: 10.2216/13-128.1Morphological studies and molecular analyses based on ribulose-1,5-bisphosphate carboxylase oxygenase large subunit (rbcL) gene sequences were the bases of our proposal to recognize Champia lubrica sp. nov. from Japan. The new species was similar to C. puertoricensis, and it was provisionally identified C. parvula in Puerto Rico (both previously assigned to C. parvula) in having cylindrical and erect thalli, conspicuous main axes, opposite branching and urceolate cystocarps; however, it differed from those two entities in its occasional verticils of three lateral branches and absence of conspicuous constrictions at diaphragms of main axes and primary laterals. Molecular–phylogenetic analyses suggested that the new species was distinct from Japanese ‘C. parvula’ as well as from Puerto Rican ‘C. parvula’ and C. puertoricensis.

Taxonomic revision of the genus Lobophora (Dictyotales, Phaeophyceae) based on morphological evidence and analyses rbcL and cox3 gene sequences

Sun Z., Hanyuda T., Lim P.E., Tanaka J., Gurgel C.F.D. and Kawai H. 2012. Taxonomic revision of the genus Lobophora (Dictyotales, Phaeophyceae) based on morphological evidence and analyses rbcL and cox3 gene sequences. Phycologia 51: 500–512. DOI: 10.2216/11-85.1A taxonomic revision of Lobophora based on molecular phylogenetic analyses of rbcL and cox3 gene sequences as well as anatomical observations was carried out, mostly based on specimens collected from eastern Asia and southeastern Australia. In the molecular phylogenetic analyses, nine major clades supported by high bootstrap values were recognized. In combination with evaluation of morphological characters, four clades were concluded to be new species. The Australian species L. australis sp. nov. possessed erect thalli with sporangial sori scattered on the ventral surface and had a closer phylogenetic relationship with another Australian species, L. nigrescens, but it was distinguished from the latter in having fewer layers of cortical cells and smaller sporangia. The Asian species L. crassa sp. nov., L. pachyventera sp. nov. and L. asiatica sp. nov. possessed decumbent thalli with sporangia scattered on the dorsal surface. Among the three prostrate species, L. crassa had a considerably thicker thallus with four to five cortical layers, L. asiatica had a thinner thallus with two cortical layers, and L. pachyventera differed from another two species by its three-layered ventral cortex and well-developed anchoring rhizoids.