Virescentia guangxiensis(Batrachospermales,Rhodophyta):a new freshwater red algal species from South China

Virescentia guangxiensis,a new species of Virescentia from Guangxi,South China,is described and illustrated based on morphological observations and phylogenetic analysis.This species was distinguished morphologically from other species by the presence of special expansion cells with a variable shape,obovoid,spherical,pear-shaped,located in the penultimate cells of primary or secondary fascicles,rarely terminal on primary fascicles,as well as by small whorls(250-350-μm wide) and short primary fascicles(5-7 cell stories).Phylogenetic analysis of molecular data from the rbcL and COI-5 P loci supported the separation of the proposed new species from other species in the genus Virescentia.This is the first species of the order Batrachospermales reported in Guangxi and the second species of the genus Virescentia reported in China.This study expands the known species diversity and geographical distribution of fre shwater Rhodophyta in China.     

Tsengiella,a new genus of delesseriaceae—(Rhodophyta) from China

A medium-sized delesseriaceous red alga has been collected from the subtidal area of the northern Huanghai Sea coast. The characteristics of the specimens precludes their being placed in any genus defined by the currently accepted criteria.Tsengiella gen. nov., withT. spinosa sp. nov., as the type and only known species, is created and allied with theHypoglossum group of the Delesserioideae (Delesseriaceae, Ceramiales, Rhodophyta). Contribution No. 1286 Academia Sinica Institute of Oceanology, Qingdao.     

Divergence time,historical biogeography and evolutionary rate estimation of the order Bangiales (Rhodophyta) inferred from multilocus data

Bangiales is the only order of the Bangiophyceae and has been suggested to be monophyletic. This order contains approximately 190 species and is distributed worldwide. Previous molecular studies have produced robust phylogenies among the red algae, but the divergence times, historical biogeography and evolutionary rates of Bangiales have rarely been studied. Phylogenetic relationships within the Bangiales were examined using the concatenated gene sets from all available organellar genomes. This analysis has revealed the topology((( Bangia, Porphyra) Pyropia) Wildemania). Molecular dating indicates that Bangiales diversifi ed approximately 246.40 million years ago(95% highest posterior density(HPD)= 194.78–318.24 Ma, posterior probability(PP)=0.99) in the Late Permian and Early Triassic, and that the ancestral species most likely originated from eastern Gondwanaland(currently New Zealand and Australia) and subsequently began to spread and evolve worldwide. Based on pairwise comparisons, we found a slower rate of nucleotide substitutions and lower rates of diversifi cation in Bangiales relative to Florideophyceae. Compared with Viridiplantae(green algae and land plants), the evolutionary rates of Bangiales and other Rhodophyte groups were found to be dramatically faster, by more than 3-fold for plastid genome(ptDNA) and 15-fold for mitochondrial genome(mtDNA). In addition, an average 2.5-fold lower dN/dS was found for the algae than for the land plants, which indicates purifying selection of the algae.     

Early development of grateloupia turuturu (Halymeniaceae, Rhodophyta)

Grateloupia turuturu is a commercial red alga with potential value in nutraceuticals and pharmaceuticals. To supplement information on its life history and verify whether carpospores can be used for seedling culture, early development of G. turuturu was investigated under culture conditions (27°C, 10-13 mol/(m2.s) in irradiance, photoperiod 10:14 h L:D). Three physiological stages were recognized by continuous microscopic observation: division stage, discoid crust stage, and juvenile seedling stage. At the beginning of the division stage, the carpospores developed germ tubes into which the carpospore protoplasm was evacuated, and then the carpospore protoplasm in the germ tubes began to divide continuously until discoid crusts formed. Finally, upright thalli appeared on the discoid crusts and developed into juvenile seedlings. It took about 60 days for carpospores to develop into juvenile seedlings. The growth parameters, including germination rate for carpospores and discoid crust diameter, were recorded. These results contribute more information on the life cycle, and at the same time are of great significance in the scaling-up of artificial seedling cultures of G. turuturu.     

Use of rapd for detecting and identifyingPorphyra (Bangiales, Rhodophyta)

Randomly amplified polymorphic DNA (RAPD) technique was applied to assess the genetic variations and phylogenetic relationships in 4 species ofPorphyra. The samples were collected from the coast of Canada, Vietnam, Zhoushan, Fujian and Qingdao in China. Amplifications with 20 primers were carried out under predetermined optimal reaction conditions (samples were first heated at 94°C for 5 min. and followed by 45 cycles of 1 min at 94°C, 1 min at 36°C, and 2 min at 72°C, then held at 72°C for 10 min). The amplified products were scored as present (1) or absent (0) for each DNA sample and an index of genetic similarity (F) was calculated by using Nei & Li’s matching coefficient method (1979). The value of (1−F) was used to quantify the genetic distances between species and construct a phylogenetic tree. The relationship indicated by the UPGMA and NJ cluster analysis on the values of the genetic distance is in good overall agreement with classical taxonomy. The obvious differences between natural and cultivated population ofP. haitanensi suggest that variation or hybridization with other species occurred during the culture. Contribution No. 100 from the Experimental Marine Biology Laboratory, IOCAS. Contribution No. 3289 from the Institute of Oceanology, Chinese Academy of Sciences. The research supported by the Foundation of the Chinese Academy of Sciences.     

Early development of Chondrus ocellatus Holm （Gigartinaceae, Rhodophyta）

1 INTRODUCTION Red algae C. ocellatus lives in temperate zone of coastal area, and inhabits at substrates from high tide to low tide regions. Its life history is composed of three phases: tetrasporophyte, gametophyte and carposporophyte. Chondrus is one o…     

Phylogenetic relationships within the genus Aspidisca (Protozoa, Ciliophora, Euplotida) revealed by ITS1-5.8S-ITS2 region sequences

The internal transcribed spacer regions (ITS1 and ITS2) and 5.8S rRNA genes were sequenced in six populations of four Aspidisca species, namely A. leptaspis, A. orthopogon, A. magna and A. aculeata. Phylogenetic trees were constructed by means of Bayesian inference (BI), Maximum Parsimony (MP), Neighbor-Joining (NJ), and Maximum Likelihood (ML) to assess the inter- and intra-species relationships within the genus Aspidisca. All trees show similar topologies with stable supports and indicate that: (1) four well known groups, i.e., Oligotrichia, Stichotrichia, Choreotrichia and Hypotrichia, are distinctly outlined within the class Spirotrichea, and all are monophyletic other than Hypotrichia; (2) members of Aspidisca can be distinguished well, based on the ITS1-5.8S-ITS2 region sequences, and A. leptaspis and A. magna shared a closer relationship than other species; (3) Aspidisca and Euplotes branch early in the subclass Hypotrichia. To compare the phylogenetic relationships based on different genes, SSU rRNA trees were also constructed with nearly the same species inclusion, which revealed different topologies of inter-species, inter-genera and inter-subclasses.     

Development of suspended conchocelis ofPorphyra haitanensis (Bangiales, Rhodophyta)

This Mar. 1993 to Aug. 1994 study on suspended conchocelis ofPorphyra haitanensis showed that there were three patterns for development of vegetative filaments: filaments to filaments by “budding”; filaments to sporangial branchlets by “budding”, or cell swelling. There were also three patterms for sporangial branchlet development: vegetatively propagating, changing into conchospores, or dying. Each developmental stage had one or more different developmental directions between vegetative filaments and sporangial branchlets. Developments from conchosporangial branchlets to conchospores were sequential and irreversible. Although sporangial branchlets formed at 29°C could give rise to filaments, they could not propagate as healthily under the same conditions as those formed at 25°C did. Probably the crucial period of plant cell differentiation is in the late stage of sporangial branchlets. In line with the developmental directions of different stages, the authors regulated the development of conchocelis to get ideal different developmental stages materials to obtain very developmentally homogeneous stages, including filaments and sporangial branchlets. Contribution No 3283 from the Institute of Oceanology, Chinese Academy of Sciences. Study supported by the Climbing Project B PD-B6-4-2 of the State Science and Technology Commission of China.     

Isolation and callus formation of Gracilariopsis bailiniae (Gracilariales,Rhodophyta) protoplasts

Journal of Oceanology and Limnology - This paper reports the first successful isolation of protoplasts from Gracilariopsis bailiniae and their callus formation. The base solution type,...     

Morphological study of the genus Herposiphonia(Rhodophyta,Rhodomelaceae) on the coast of eastern Guangdong,China, with a description of H. pinnata sp. nov.

We present a taxonomic study of taxa of the red algae genus Herposiphonia(Rhodophyta, Rhodomelaceae), collected from the coast of eastern Guangdong, China. We made detailed morphological studies and considered recent taxonomic criteria for species delimitation, and are making the first report of five diff erent species on the coast of Guangdong, including a new species. The species identified were H. caespitosa Tseng, H. hollenbergii Dawson, H. pecten- veneris(Harvey) Falkenberg, H. subdisticha Okamura and H. pinnata Ding and Tan sp. nov. H. pinnata sp. nov. is characterized by bright green thalli; most parts of the feathery thalli are free of the substratum; determinate branches and indeterminate branches are arranged in a chaotic sequence; the primary axis has bare segments; the determinate branch has 9–11 periaxial cells per segment; vegetative trichoblasts are abundant; and tetrasporangia are formed on the middle of the determinate branch with 1–8 successive segments in a single rectilinear series. This paper is also the first record of sporophyte plants of H. pecten-veneris.     

Induction and cultivation of cloned filaments of Polysiphonia urceolata (Rhodomelaceae, Rhodophyta)

A filamentous clone of Polysiphonia urceolata was regenerated from segments cut from the fronds of gametophytes. Unlike wild thalli with short virgate branchlets, the clone was filamentous with few branches. Many transparent trichoblasts arose from pericentral cells during the induction culture, but these were seldom observed during normal growth. The trichoblasts were uniseriate, often colorless, and formed lobed rhizoids rapidly when they came into contact with solid substrates. In addition to morphological characteristics, the photosynthetic properties and growth conditions of the clone differed from those of the mother plant. Cross-gradient light and temperature culture experiments revealed that the most favorable conditions for culture of the filamentous clone were 22°C and 95-120 μE/(m2-s) light intensity. The photosynthetic light saturation value for filaments was approx. 100 μE/(m2-s), which is far lower than that of wild thalli. These results could be used to develop techniques for mass cultures of P. urceolata in photobioreactors for production of seed stock or bioactive products.     

Formation and early development of tetraspores of Polysiphonia urceolata （Rhodomelaceae, Rhodophyta）

Polysiphonia urceolata is one type of potential commercial red seaweeds used for breeding and cultivation, because of its significant biochemical and biomedical application. However, the information of breeding and seedling incubation for cultivation is limited, especially the early development. In this study, tetrasporohyte and gametophyte of P. urceolata were taken as the study materials in Huiquan Bay, Qingdao, China. The cleaned and sterilized tetrasporophytes and gametophytes were pre-cultured in sterilized seawater, then nurtured at 18°C, 25 μmol photons m⁻² s⁻¹ in 12:12 h (light:dark) photoperiod. Continuous observation under microscope showed that the early development consists of bipolar division stage and seedling stage. In the division stage, tetraspores germinate into bipolar sporelings that further differentiate into a colorless rhizoidal portion and a lightly pigmented upright shoot. The lightly pigmented rhizoidal cell develops to a rhizoid and the larger pigmented cell transforms to an erect axis. In the seedling stage, several quasi-protuberances appear on the erect axis and form juvenile seedlings. The results demonstrate the culture of P. urceolata from tetraspores under laboratory conditions. Supported by National Key Technology Support Program, Development Program of China (No.2006AA09Z21), National Natural Science Foundation of China (No. 40618001 and N_CUHK438/06) and Shandong Agricultural Seed Stock Breeding Project     

Formation and early development of tetraspores of Polysiphonia urceolata (Rhodomelaceae, Rhodophyta)

Polysiphonia urceolata is one type of potential commercial red seaweeds used for breeding and cultivation, because of its significant biochemical and biomedical application. However, the information of breeding and seedling incubation for cultivation is limited, especially the early development. In this study, tetrasporohyte and gametophyte of P. urceolata were taken as the study materials in Huiquan Bay, Qingdao, China. The cleaned and sterilized tetrasporophytes and gametophytes were pre-cultured in sterilized seawater, then nurtured at 18℃, 25 μmol photons m-2 s-1 in 12:12 h (light:dark) photoperiod. Continuous observation under microscope showed that the early development consists of bipolar division stage and seedling stage. In the division stage, tetraspores germinate into bipolar sporelings that further differentiate into a colorless rhizoidal portion and a lightly pigmented upright shoot. The lightly pigmented rhizoidal cell develops to a rhizoid and the larger pigmented cell transforms to an erect axis. In the seedling stage, several quasi-protuberances appear on the erect axis and form juvenile seedlings. The results demonstrate the culture of P. urceolata from tetraspores under laboratory conditions.     

Three new species of Batrachospermum Roth （Batrachospermaceae, Rhodophyta） in China

Three new species of Batrachospermum Roth (Batrachospermales, Rhodophyta) from China are described in this paper. B. yunnanense sp. nov. has long-cylindrical trichogynes with long stalks and is diagnostic of section Virescentia. Within this section, B. yunnanense is similar to B. helminthosum Bory emend. Sheath et al., but it is dioecious and has curved carpogonial branches, while the latter is monoecious and has straight carpogonial branches. It is also similar to B. transtaganum Reis, but it differs from the latter in long carpogonia,big carposporophytes and carposporangia. It is considered that B. nothocladoideum sp. nov. is assigned to section Contorta, subsection Kushiroense, because its carpogonial branches are twisted and gonimoblast filaments are loosely agglomerated. This new species similar to B. iriomotense Kumano, but with short fascicles, long-ovoid or subpyriform cells, numerous terminal hairs, long-ellipsoid trichogynes, big carposporophytes and small carposporangia. The plant is quite tough and cartilaginous and similar to Nothocladus in gross morphology, but its carposporophytes are compact instead of diffuse. This shows that it may be a transitional species between section Contorta and genus Nothocladus. So, B. transitorium sp. nov. should belong to section Contorta, subsection Kushiroense, because of its curved or twisted carpogonial branches and loosely agglomerated gonimoblast filaments, with globose or subglobose cells in fascicles similar to B. spermatiophorum Vis et Sheath, but no colourless spermatiophores. In terms of small and numerous carposporophytes, B. transitorium sp. nov. is similar to some species of section Batrachospermum. However, their other features are unique, indicating its transitional nature between section Contorta and Batrachospermum.     

Three new species of Batrachospermum Roth (Batrachosper-maceae,Rhodophyta) in China

1 INTRODUCTION The first published records of genus Batra-chospermum Roth in China are from Jao (1941), when eleven taxa were reported. Since then, Shi, Hu and Kumano (1993), Shi (1994a, 1994b), Hua and Shi (1996), Xie et al. (1999, 2003), Xie and Shi (2003) have described in more detail the species from China. To date, 23 taxa of Batrachospermum Roth in China have been reported, of which, B. yunnanense, B. nothocladoideum and B. transito-rium are new species of this genus, and are…     

Cloning and Analysis of Calmodulin Gene from Porphyra yezoensis Ueda （Bangiales, Rhodophyta）

In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chain reaction (PCR) based on the analysis of P. yezoensis ESTs from dbEST database. The result shows that the full-length cDNA of CaM consists of 603 bps including an ORF encoding for 151 amino acids and a terminate codon UGA, while the length of genomic sequence is 1231 bps including 2 exons and 1 intron. The average GC content of the coding region is 58.77%, while the GC content of the third position of this gene is as high as 82.23%. Four Ca²⁺ binding sites (EF-hand) are found in this gene. The predicted molecular mass of the deduced peptide is 16688.72 Da and the pI is 4.222. By aligning with known CaM genes, the similarity of CaM gene sequence with homologous genes in Chlamydomonas incerta and Chlamydomonas reinhardtii is 72.7% and 72.2% respectively, and the similarity of the deduced amino acid sequence of CaM gene with homologous genes in C. incerta and C. reinhardtii are both 71.5%. This is the first report on CaM from a species of Rhodophyta.     

Cloning and Analysis of Calmodulin Gene from Porphyra yezoensis Ueda (Bangiales, Rhodophyta)

In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensiss,cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chain reaction (PCR) based on the analysis of P. yezoensis ESTs from dbEST database. The result shows that the full-length cDNA of CaM consists of 603 bps including an ORF encoding for 151 amino acids and a terminate codon UGA, while the length of genomic sequence is 1231 bps including 2 exous and 1 intron. The average GC content of the coding region is 58.77%, while the GC content of the third position of this gene is as high as 82.23%. Four Ca2+ binding sites (EF-hand) are found in this gene. The predicted molecular mass of the deduced peptide is 16688.72 Da and the pI is 4.222. By aligning with known CaM genes, the similarity of CaM gene sequence with homologous genes in Chlamydomonas incerta and Chlamydomonas reinhardtii is 72.7% and 72.2% respectively, and the similarity of the deduced amino acid sequence of CaM gene with homologous genes in C. incerta and C. reinhardtii are both 71.5%. This is the first report on CaM from a species of Rhodophyta.     

The first complete organellar genomes of an Antarctic red alga,Pyropia endiviifolia:insights into its genome architecture and phylogenetic position within genus Pyropia(Bangiales,Rhodophyta)

Pyropia species grow in the intertidal zone and are cold-water adapted. To date, most of the information about the whole plastid and mitochondrial genomes(ptDNA and mtDNA) of this genus is limited to Northern Hemisphere species. Here, we report the sequencing of the ptDNA and mtDNA of the Antarctic red alga Pyropia endiviifolia using the Illumina platform. The plastid genome(195 784 bp, 33.28% GC content) contains 210 protein-coding genes, 37 tRNA genes and 6 rRNA genes. The mitochondrial genome(34 603 bp, 30.5% GC content) contains 26 protein-coding genes, 25 tRNA genes and 2 rRNA genes. Our results suggest that the organellar genomes of Py. endiviifolia have a compact organization. Although the collinearity of these genomes is conserved compared with other Pyropia species, the genome sizes show significant differences, mainly because of the different copy numbers of rDNA operons in the pt DNA and group II introns in the mtDNA. The other Pyropia species have 2–3 distinct intronic ORFs in their cox 1 genes, but Py. endiviifolia has no introns in its cox 1 gene. This has led to a smaller mtDNA than in other Pyropia species. The phylogenetic relationships within Pyropia were examined using concatenated gene sets from most of the available organellar genomes with both the maximum likelihood and Bayesian methods. The analysis revealed a sister taxa affiliation between the Antarctic species Py. endiviifolia and the North American species Py. kanakaensis.     

Biomass and carbon storage of Gracilariopsis lemaneiformis （Rhodophyta） in Zhanshan Bay,Qingdao, China

Marine macroalgae can absorb carbon and play an important role in carbon sequestration. As an important economic macroalga, Gracilariopsis lemaneiformis has the potential to significantly affect carbon absorption and storage in wave-sheltered intertidal reef systems. However, detailed knowledge on seasonal biomass changes and carbon storage of G. lemaneiformis is lacking, especially in many small and scattered ecosystems. Considering the influence of human activities on wild distribution of G. lemaneiformis, the understanding of seasonal dynamics of an economically important species in nature is necessary. In this study, we first investigated seasonal variations in biomass, coverage area, and carbon storage during low tide from August 2011 to July 2012 in Zhanshan Bay, Qingdao, China. Furthermore, we estimated the carbon storage potential of wild G. lemaneiformis using light use efficiency(LUE). The results show that the standing biomass and coverage area changed significantly with season. However, seasonal variations in carbon content and water content were not obvious, with an average content of 35.1% and 83.64%, respectively. Moreover, carbon storage in individual months varied between 0.67 and 47.03 g C/m 2, and the value of carbon storage was the highest in August and June and the lowest in February. In Zhanshan Bay, LUE of G. lemaneiformis was only 0.23%. If it is increased to the theoretical maximum(5%–6%), the carbon storage will have an increase of at least 21 times compared with the current, which suggested that carbon storage of wild G. lemaneiformis had a high enhancement potential. The study will help to assess a potential role of G. lemaneiformis in reducing atmospheric CO2.     

中国红质藻科(Erythropeltidaceae)5个新记录种

报道中国红质藻科的新记录种,尖根星丝藻Erythrotrichia biseriata,加粗星丝藻E.incrassata,日本星丝藻E.japonica,垫状星丝藻E.pulvinata,分枝星丝藻E.welwitschii。