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SUMMARY: A 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. [ABSTRACT FROM AUTHOR]

SUMMARY: A new species of the southern hemisphere genus Clymene, C. sutherlandiae, is described based on collections from the Otago coast, south east South Island of New Zealand, and from a site in western Tasmania. Found on mid‐upper intertidal rocks on open coasts, and frequently adjacent to sandy shores, this is a second species for the genus, previously known solely from the type species C. coleana found in the North Island, northern South Island and Chatham Islands of New Zealand. [ABSTRACT FROM AUTHOR]

SUMMARY: In this study, we applied a chemostat culture method, for the first time, to measure the nutrient uptake rate of macroalgae. We examined two methods of measuring the nutrient uptake rate of two macroalgae, Saccharina japonica var. religiosa and Ulva australis, by comparing nutrient uptake kinetics between the chemostat culture and batch culture. In the chemostat culture, the nutrient concentration was kept constant by monitoring the change in nutrient concentration using an Auto Analyzer in real time and adding nutrients to compensate for the macroalgae's nutrient consumption. The nutrient uptake in the chemostat culture could be best fitted to the Michaelis–Menten saturation kinetics. In the batch culture, the nutrient concentration decreased with time, either constantly or exponentially due to a rapid uptake of nutrients by the macroalgae. The nutrient uptake rate in the batch culture generally showed a scattered relationship with nutrient concentration, with a weak fitting to the Michaelis–Menten saturation kinetics. This discrepancy seemed to be partly because the change in nutrient concentration was large between the sampling intervals in the batch culture. Determining an appropriate sampling interval for detectable concentration change is difficult unless the nutrient concentration is measured in real time. Therefore, the application of the chemostat culture method to the measurement of the uptake rate by macroalgae could greatly improve our understanding of nutrient uptake kinetics. [ABSTRACT FROM AUTHOR]

SUMMARY: Zonation patterns and the structure of intertidal communities are controlled by tidal conditions. Algal diversity, abundance and succession were experimentally tested under different degrees of wave exposure, shore level, and season of clearing at the intertidal zone, Phuket, Thailand. Dead coral patches colonized by algae (20 cm × 20 cm) were cleared at upper, middle, and lower shore levels on sheltered and semi‐exposed shores during both the dry and rainy seasons. Of 17 algal species, including eight Rhodophyta, eight Chlorophyta, and one Phaeophyceae that were recruited on the cleared plots, three species were dominant: Ulva paradoxa, Padina in the Vaughaniella stage, and Polysiphonia sphaerocarpa. Algal diversity on the semi‐exposed shore was higher than on the sheltered shore. In the successional process, U. paradoxa extensively recruited and persisted longer on plots cleared at the middle shore level on the semi‐exposed shores than at the other. It showed a greater abundance in the plots cleared in the rainy season than those cleared in the dry season. Ulva paradoxa persisted for around 5 to 6 months after clearing and was then replaced by the two later species, Padina in the Vaughaniella stage and P. sphaerocarpa. Ulva paradoxa settled more easily and persisted longer at the cleared plots than other algal species because of its opportunistic characteristics and a special physiological adaptation to long periods of emersion. From this study, degree of wave exposure, shore level, and season of clearing likely play important roles in algal recruitment, abundance, and succession patterns. [ABSTRACT FROM AUTHOR]

Summary: A new red alga from Japan, Dasya japonovillosa, is described. This new species and D. enomotoi, both of which have elongated axes densely covered with numerous soft monosiphonous filaments, may have been misidentified as D. villosa by previous investigators in Japan. Dasya villosa differs from D. japonovillosa and D. enomotoi in the distinct five pericentral cells in transverse sections and palisade‐like tetrasporangial cover cells. The new species is distinguished from several similar species by the combination of the following: an elongated axis (to 65 cm), subdichotomously divided axes and polysiphonous branches, indistinct pericentral cells in transverse sections except near the apices, and the presence of enlarged, inner cortical cells, radially arranged numerous soft monosiphonous filaments, three‐celled carpogonial branches, four tetrasporangia in each fertile segment of the stichidia, and one (rarely two) tetrasporangial cover cell that is not elongated longitudinally and rarely divided transversely. [ABSTRACT FROM AUTHOR]

SUMMARY: Although the green seaweed Ulva is one of the most common seaweeds in the coastal regions with well‐studied ecological characteristics, few reverse genetic technologies have been developed for it. The clustered regularly interspaced short palindromic repeats (CRISPR)‐Cas9 system is a simple genome‐editing technology based on a ribonucleoprotein (RNP) complex composed of an endonuclease and programmable RNA to target particular DNA sequences. Genome editing makes it possible to generate mutations on a target gene in non‐model organisms without established transgenic technologies. In this study, we applied the CRISPR‐Cas9 RNP genome‐editing system to the green seaweed Ulva prolifera, using polyethylene glycol (PEG)‐mediated transfection. Our experimental system disrupts a single gene (UpAPT) encoding adenine phosphoribosyl transferase (APT) and generates a resistant phenotype for gametophytes cultured in a medium with toxic compound 2‐fluoroadenine. The PEG‐mediated transfection used for gametes resulted in 2‐fluoroadenine‐resistant strains containing short indels or substitutions on UpAPT. Our results showed that the CRISPR‐Cas9 system with PEG‐mediated transfection was efficient for genome editing in Ulva. [ABSTRACT FROM AUTHOR]

SUMMARY The effect of drying on two brown seaweed (Treptacantha abies‐marina and Cystoseira humilis) and two red seaweed species (Asparagopsis armata and Asparagopsis taxiformis) was evaluated based on the levels of biological activity, such as antioxidant and anti‐inflammatory properties. Moreover, the contents of some significant compound classes, such as polyphenols and beta‐glucans, were determined. Seaweeds C. humilis and T. abies‐marina showed high polyphenol levels (1.76–6.78 mg gallic acid equivalents g−1 dw), which clearly exceeded those determined in the Asparagopsis genus regardless of drying process. This was partially reflected in the antioxidant activity as measured by DPPH and FRAP methods, which showed that extracts from C. humilis and T. abies‐marina in most cases had stronger antioxidant activity than those from Asparagopsis species. The influence of the drying technique upon the antioxidant activity was relatively limited, since in many instances there was no effect. Concerning anti‐inflammatory activity, in the case of shade‐dried samples, C. humilis had a higher activity (>30% COX‐2 inhibition) than A. armata. However, this activity in C. humilis was not rendered available in the upper gastrointestinal (GI) tract. Indeed, only A. taxiformis displayed anti‐inflammatory activity in the fraction available in the upper GI tract, showing an upper GI tract availability in the 90–100% range. Therefore, though bioactivity levels were higher in C. humilis and T. abies‐marina, Asparagopsis species also had substantial levels of bioactive compound. Sun‐drying produced more negative effects than shade‐drying, but these effects were not very extensive. [ABSTRACT FROM AUTHOR]

SUMMARY: Genetic analysis of type material of various Ulva species has shown that many names have been misapplied. DNA sequences of two of the specimens on the lectotype sheet of U. australis from South Australia showed that U. australis is conspecific with specimens called U. pertusa from Japan. However, type material of U. pertusa has not been sequenced, nor have other type specimens with type localities in Japan and Australia, including U. conglobata f. conglobata and U. conglobata f. densa from the former, and U. laetevirens and U. spathulata from the latter. To determine if these names have been correctly applied, targeted DNA sequencing of the rbcL gene was performed on (i) the lectotype specimen of U. laetevirens, (ii) the lectotype and two syntype specimens of U. pertusa, (iii) the lectotype and two syntype specimens of U. congoblata f. conglobata and (iv) two specimens on the holotype sheet of U. conglobata f. densa. In addition, high‐throughput sequencing (HTS) analysis was carried out on an isotype specimen of U. spathulata. Phylogenetic analysis of the resulting rbcL gene sequences supports the taxonomic conclusions that U. laetevirens, U. pertusa and U. spathulata are synonyms of U. australis, and U. conglobata f. conglobata and U. conglobata f. densa represent a single separate and distinct species, U. conglobata. These genetic data contribute to the taxonomy of Ulva and further demonstrate that analyzing DNA from type material is the only currently known reliable method to correctly apply names in this genus. [ABSTRACT FROM AUTHOR]

Summary: The freshwater red alga Nemalionopsis shawii Skuja is first reported for mainland China from specimens collected in Guangdong and Yunnan Province. Morphological observations and molecular sequences of rbcL and cox1 genes were used to identify and analyze the phylogenetic position of the samples. Samples from China formed a monophyletic clade with other N. shawii samples from Japan, Indonesia, and Nepal with robust support values. The pairwise genetic distances for N. shawii between the samples from China and other samples were 0.2–1.5% and 1.0–2.4% for rbcL and cox1, respectively. Both male and female reproductive structures were observed in the specimens from Guangdong, but only monosporangia in the specimen from Yunnan. The samples from China increase the diversity of morphological measurements for N. shawii. The discovery of this genus in mainland China results in a new record of a freshwater red alga for this country. [ABSTRACT FROM AUTHOR]

SUMMARY The rare red alga Schimmelmannia (Schimmelmanniaceae, Acrosymphytales) from Japan was taxonomically re‐examined in this study. Japanese Schimmelmannia has previously been identified as S. plumosa (Setchell) I.A.Abbott. However, Japanese Schimmelmannia and S. plumosa have approximately 5 and 1.9% of genetic distance in mitochondrial cox1 and chloroplast rbcL sequences, respectively. They also differ morphologically in the numbers of periaxial cells and auxiliary cell branches indicating that they are distinct species. Based on molecular phylogenetics and morphology, S. benzaiteniana is distinguishable from other Schimmelmannia species, except for S. bollei Montagne which lacks a detailed description. Since S. bollei has been reported only from the North Atlantic coast of Africa, we assumed that it is distinct from the Japanese species. We, therefore, described the Japanese species as a new species, S. benzaiteniana. [ABSTRACT FROM AUTHOR]

SUMMARY: The discovery of a plethora of cryptic species in many algal groups has led to speculation as to the causes of this observation and has affected taxonomy, with reluctance to give names to species that look identical. While this is defensible for monophyletic cryptic species complexes, both our understanding of similar morphologies (crypsis) and nomenclature is challenged when we encounter non‐monophyletic ‘cryptic’ species. Bostrychia simpliciuscula is a wide‐ranging species in which multiple cryptic species are known. Our increased sampling shows that this species consists of four lineages that do not form a clade, but lineages are sister to species with different morphologies. Careful morphological examination shows that characters, especially branched monosiphonous laterals and rhizoid morphology in haptera, are able to distinguish these four lineages into two groups, that are still not monophyletic. The similar morphologies in these lineages could be due to convergence, but not developmental constraints or lack of time to diverge morphologically; or possibly maintenance of a generalized body plan. These lineages appear to have specific biogeographic patterns and these will be used to propose a new taxonomy. B. simpliciuscula is now confined to the tropics. Another of these lineages matches a previously described species, B. tenuissima, that was synonymized with B. simpliciuscula and is from cold temperate Australasia, and is resurrected. Another lineage is found in Japan in which a previous name is also available, B. hamana‐tokidae; the last lineage is found in central New South Wales, morphologically it resembles B. tenuissima, with which it overlaps in distribution around Sydney, and is named as a new species, B. kingii sp. nov. [ABSTRACT FROM AUTHOR]

SUMMARY We here report a new Dasya species found in a landlocked fjord or poll in southwestern Norway; Dasya adela sp. nov. The thallus of this species is small (1-3 cm), normally sparsely branched, and its axes are completely covered with cortex cells. The species is set with long (3-4 mm) and flaccid monosiphonous pseudolaterals, and during autumn it showed high growth of adventitious monosiphonous branches. Only a few individuals with tetrasporangia have been recorded, and no sexual reproductive structures have been observed in field collections. In culture stichidia readily developed on the pseudolaterals, with four tetrasporangia per section. The spores showed high mortality. A few sporelings survived in culture, and developed into small and loosely organized filaments with no upright axes. After 2 years in culture a few plants bearing spermatangial branches were observed, but no individuals with carpogonia. The monosiphonous branches are readily shed in culture, attach themselves by rhizoids and rapidly develop into new thalli, some of which have produced tetrasporangial stichidia. Sequences analyses of partial COI and the rbc L gene showed that the new taxon belongs within Dasyoideae. However, no close relationship was found with other European species of Dasya. The new taxon was compared to other Dasya taxa with which it shared a number of selected characters, but none of these taxa shared all characters of the new Dasya. [ABSTRACT FROM AUTHOR]

Laurencia laurahuertana Mateo- Cid, Mendoza- González, Sentíes & Díaz- Larrea sp. nov. is described from Quintana Roo, Mexican Caribbean, on the basis of comparative morphology and ribulose bisphosphate carboxylase gene sequence analysis. It is distinguished from other Laurencia species by the small size of the sporophytes and dioecious gametophytes, the branching thalli, and its epiphytic habits. The phylogenetic analysis showed that the Mexican Caribbean sample, from Punta Herrero ( Quintana Roo), formed a distinctive and well supported clade segregated from other species of Laurencia from Brazil and Mexico. The Mexican entity is morphologically and genetically distinct from other Laurencia species, warranting description as a new species. [ABSTRACT FROM AUTHOR]

A new red alga, Dasya enomotoi, is described from Japan. This species is characterized by having a large thallus consisting of an elongated axis and many, radially arranged, polysiphonous branches both of which are heavily corticated and densely covered with numerous, soft monosiphonous filaments. It is distinguished from several similar species by the combination of the following: (i) indistinct pericentral cells in transverse sections except near the apices, (ii) the presence of enlarged, inner cortical cells, (iii) radially arranged adventitious monosiphonous filaments, (iv) three-celled carpogonial branches, (v) six (sometimes five) tetrasporangia in each fertile segment of the stichidia, and (vi) three tetrasporangial cover cells that are not elongated longitudinally and usually not divided transversely. This species may have been identified as D. villosa Harvey by previous investigators in Japan. [ABSTRACT FROM AUTHOR]

Previous studies suggested that the biodiversity of the mangrove-associated Bostrychia radicans/Bostrychia moritziana species complex on the Pacific coast of Central America, based on genetic and reproductive data, were low compared with similar areas on the Atlantic coast. Evolutionary scenarios were proposed based on either a recent introduction to the Pacific, or a more uniform environment leading to genetically connected populations and low differentiation between populations. We sampled more extensively in southern Mexico, Guatemala and El Salvador and sequenced the samples for the RuBisCo spacer. Our results show that genetic diversity is high in these populations. Many haplotypes retrieved are also found in the Atlantic Ocean (USA, Brazil), an observation not made before. Data suggest that populations are highly differentiated with little evidence of isolation-by-distance. The population at La Puntilla, El Salvador is highly differentiated from other populations. Data also suggest that diversity is reduced in a northerly direction, with only one haplotype, unique to Pacific Central America, found north of Chiapas, Mexico. This could be due to northern expansion of this unique genotype as sea surface temperatures ameliorated following the last glacial maximum. Our data do not support the previous proposition of low diversity in the east central Pacific and suggest that much of the Pacific Central America diversity is from before the closure of the Isthmus of Panama. [ABSTRACT FROM AUTHOR]

The worldwide production of the gelling agent agar mainly rely on the red algae of the order Gracilariales and Gelidiales for raw material. We investigate here the potential of a species from another red algal order, Ceramiales as an agar source. The agar from Laurencia flexilis collected in northern Philippines was extracted using native and alkali treatment procedures and the properties of the extracts were determined using chemical, spectroscopic and physical methods. The native agar, 26% dry weight basis, forms a gel with moderate gel strength (200 g cm−2). Alkali-treatment did not enhance the gel strength, indicating insignificant amounts of galactose-6-sulfate residue, the precursor of the gel-forming 3,6-anhydrogalactose (3,6-AG) moieties. Furthermore, the Fourier transform infrared and chemical analysis showed low sulfate and high 3,6-AG levels, not affected significantly by the alkali treatment. Nuclear magnetic resonance spectroscopic analysis revealed 3-linked 6- O-methyl-D-galactose and 4-linked 3,6-anhydro-L-galactose as the major repeating unit of the native extract, with minor sulfation at 4-position of the 3-linked galactose residues. The native and alkali treated agars have comparably high gelling and melting temperatures, whereas the former exhibits higher gel syneresis. Laurencia flexilis could be a good source of agar that possesses physico-chemical and rheological qualities appropriate for food applications. Due to the inability of alkali treatment to enhance the key gel qualities of the native extract, it is recommended that commercial agar extraction from this seaweed would be done without pursuing this widely-used industrial procedure. [ABSTRACT FROM AUTHOR]

The first occurrence of Palisada maris-rubri (K.W. Nam et Saito) K.W. Nam (Ceramiales, Rhodomelaceae) from the Mediterranean Sea, is reported. To date the species was known only from tetrasporic specimens from the type locality (Ras Muhammed, Sinai, Egypt, Red Sea). Mediterranean thalli share nearly all vegetative and reproductive features with Red Sea specimens showing more robust thalli with axes to 3 mm broad and ultimate branchlets to 1000 µm broad, absence of intercellular spaces between medullary cells and epidermal cells in transverse section with a palisade arrangement. Male and cystocarpic thalli are recorded for the first time. Moreover, the analysis of characters of three species of Chondrophycus previously known from the Mediterranean Sea ( C. patentirameus (Montagne) K.W. Nam, C. tenerrimus (Cremades) G. Furnari et al. and C. thuyoides (Kützing) G. Furnari) led us to conclude that they belong to the genus Palisada. The following new combinations are formally proposed: P. patentiramea (Montagne) Serio et al., P. thuyoides (Kützing) Serio et al., P. tenerrima (Cremades) Serio et al. [ABSTRACT FROM AUTHOR]

Two species of Dasya in the Dasyaceae (Ceramiales, Rhodophyta) are reported from Bonin Islands, southern Japan. Dasya murrayana Abbott et Millar, new to Japan, is characterized by the following set of features: the tufted habit (up to 30 erect axes developing from a basal disc), small-sized (6–10 mm high and 350–500 μm in diameter in the middle region), thinly but completely corticated axes, rigid and incurved pseudolaterals forming corymbose heads at the apices of axes and branches, the absence of adventitious monosiphonous filaments, a large number of tetrasporangial stichidia and spermatangial branches per fertile pseudolateral and slender spermatangial branches (35–45 μm in diameter). Dasya boninensis Masuda, Kurihara et Kogame, sp. nov. is characterized by short but thick (10–30 mm high and 600–1000 μm in diameter at the middle portion), heavily corticated axes, indistinct pericentral cells except for the upper portion in transverse sections, soft, straight pseudolaterals and adventitious monosiphonous filaments densely covering the axis and branches, a small number of tetrasporangial stichidia and spermatangial branches per fertile pseudolateral, thick spermatangial branches (65–90 μm in diameter), and short-necked cystocarps. A dichotomous key to the taxa found in Japanese waters is given. [ABSTRACT FROM AUTHOR]

Three species of the red algal genus Herposiphonia (Ceramiales, Rhodomelaceae) found in Japan are described, and taxonomic features of the genus are discussed. Herposiphonia crassa Hollenberg is reported from Japan for the first time and is characterized by thick axes (200–350 µm in diameter) and determinate branches (100–200 µm in diameter), relatively short determinate laterals (400–1200 µm in length) with a large number of periaxial cells (15–19 per segment) and three (occasionally two or four) vigorously developed (1.8–2.5 mm in length by 50–75 µm in diameter basally) trichoblasts on each determinate lateral. Herposiphonia elongata Masuda et Kogame is also reported from Japan for the first time and is characterized by the conspicuous thickening growth of cystocarp-bearing branches and spermatangial branches with an elongated sterile tip. Some newly found features of Herposiphonia fissidentoides (Holmes) Okamura are presented: the rhizoid production from the central portion of parental periaxial cells in addition to the distal end, virtual absence of vegetative trichoblasts, production of procarpial trichoblasts and spermatangial branches on fertile determinate branches on short indeterminate laterals, cystocarps sometimes with a short spur, and extremely large tetrasporangia. [ABSTRACT FROM AUTHOR]

Three species in the red algal order Ceramiales, Dasya longifila Masuda et Uwai (Dasyaceae), Endosiphonia horrida (C. Agardh) P. Silva (Rhodomelaceae) and Laurencia flexilis Setchell (Rhodomelaceae), are reported from Japan for the first time, and their morphological features are described along with taxonomic comments. Our findings point to the northernmost limit of geographic distribution of these species in the north-western Pacific. Dasya longifila is characterized by small, sparsely corticated axes, long pseudolaterals in which intercalary cell divisions take place, and a small number of tetrasporangial stichidia and spermatangial branches per fertile pseudolateral. Endosiphonia horrida is characterized by frequently anastomosing branches that form a bush-like tuft without a percurrent axis, inner cortical cells becoming the same length as the axial and periaxial cells, and luxuriously developed, unbranched trichoblasts. Laurencia flexilis is characterized by numerous cartilaginous rigid axes developing from a basal disc without creeping branches, the production of 4 periaxial cells per vegetative segment and the absence of longitudinally oriented secondary pit-connections between contiguous superficial cortical cells. [ABSTRACT FROM AUTHOR]

After detailed observations of type material and other collections, five Hawaiian species of Polysiphonia Greville, nom. cons. are recognized to be species of Neosiphonia M. S. Kim et I. K. Lee; namely, Neosiphonia apiculata (Hollenberg) Masuda et Kogame, Neosiphonia beaudettei (Hollenberg) M. S. Kim et Abbott , comb. nov., Neosiphonia hawaiiensis (Hollenberg) M. S. Kim et Abbott , comb. nov., Neosiphonia profunda (Hollenberg) M. S. Kim et Abbott, comb. nov., and Neosiphonia rubrorhiza (Hollenberg) M. S. Kim et Abbott, comb. nov. These five species are ecorticate, having lateral branch initials and trichoblasts produced on successive segments, rhizoids separated from pericentral cells by a cross wall, three-celled carpogonial branches (not seen in N. beaudettei and N. rubrorhiza), spermatangial branches arising on a primary branch of the trichoblasts, and tetrasporangia in a spiral series. Although certain characters were not available for some species, all other characters occur in a combination that is unique for members of Neosiphonia. [ABSTRACT FROM AUTHOR]

Cellular pH estimated from cell extract pH, and the ion compositions of major inorganic ions (Na+, NH4+, K+, Mg2+, Ca2+, Cl–, Br–, NO3–, SO42–) were studied by ion chromatography in 15 species of 4 orders (Cladophorales, Codiales, Siphonocladales and Ulvales) of Ulvophyceae and 49 species of 8 orders (Bangiales, Ceramiales, Corallinales, Cryptonemiales, Gelidiales, Gigartinales, Nemaliales and Rhodymeniales) of Rhodophyceae. Among the Rhodophyceae, relatively low intracellular pH (approximately 2.0 within cells) and high concentration of SO42– was demonstrated in Plocamium telfairiae (Harvey) Harvey. Furthermore, five species of Hypnea Lamouroux were shown to contain high concentrations of SO42– balanced by relatively high concentrations of Na+. Among the Ulvophyceae, Codium cylindricum Holmes and Ulva pertusa Kjellman contained high concentrations of SO42– balanced by relatively high concentrations of Mg2+. [ABSTRACT FROM AUTHOR]

Caloglossa released tetraspores only during dark periods in contrast to a marked light-period release exhibited by Murrayella. Both could be readily converted to a reversed light–dark cycle after a lag period of 1 day. Maximum tetraspore discharge by Caloglossa occurred approximately 4–5 h after the onset of darkness and by Murrayella 4–5 h after the onset of light. Neither 8- nor 16-h light periods affected spore release patterns in Caloglossa, while in Murrayella the spore release pattern was briefly disrupted by short day lengths, but recovered after several days. In both genera, the rhythmicity was disrupted in periods of continual darkness or continual light and appeared to be independent of light quality; however, minimum irradiance levels were critical to maintenance of release patterns. Possible mechanisms of tetraspore discharge periodicity are discussed but since both plants typically have a limited habitat as epiphytes on mangrove trunks and pneumatophores, any speculations as to the adaptive advantages of each pattern tend toward mutual contradiction. [ABSTRACT FROM AUTHOR]

The marine red alga Laurencia mariannensis Yamada (Rhodomelaceae, Ceramiales) is characterized by pale rose-red, softly fleshy, slender, terete axes (up to 600 μm in diameter), arising from a loosely entangled, stoloniferous basal system among species that have the following combination of features: the presence of longitudinally orientated secondary pit-connections between contiguous superficial cortical cells; the presence of projecting superficial cortical cells at the upper portions of branches; and the presence of lenticular thickenings in the walls of medullary cells. Furthermore, the presence of two or three corps en cerise per superficial cortical cell and one per trichoblast cell may characterize the species. [ABSTRACT FROM AUTHOR]

The concentrations of mannitol and floridean starch were determined in a 1-year field study of the epiphytic red alga Caloglossa leprieurii (Montagne) J. Agardh from warm temperate waters of eastern Australia. Seasonal environmental data for air and water temperature, day length and rainfall were recorded. The mannitol content and the floridean starch content varied significantly between collections but no seasonal responses were observed, nor were the contents correlated with any of the abiotic factors. A possible function of the starch pool as a supply for respiratory substrates under emergent conditions is discussed. All data indicate that productivity and biomass of C. leprieurii are affected by short-term abiotic and/or biotic conditions rather than controlled directly by seasonally fluctuating environmental factors. In addition, the activity of three highly specific enzymes (mannitol-1-phosphate dehydrogenase, mannitol-1-phosphatase, mannitol-dehydrogenase) and one non-specific enzyme (hexokinase), all of which are involved in the mannitol cycle, were measured in cell-free extracts every 2 weeks. All enzymes showed marked changes in activity over the year, but again no clear patterns emerged, neither with season nor in relationship to one another. On the basis of the results here, C. leprieurii is considered to be a 'season responder' rather than a 'season anticipator'. [ABSTRACT FROM AUTHOR]

The red alga Laurencia nipponica Yamada (Rhodo- melaceae, Ceramiales) is known to contain several chemical races, each of which is characterized by a particular, major halogenated secondary metabolite. Both field-collected and cultured plants of a population of this species found recently at Shikanoshima Island, Fukuoka Prefecture, southern Japan, produced C15 bromoethers, (3E)-laureatin and (3E)-iso- laureatin, and sesquiterpenoids, 2, 10-dibromo-3- chloro-9-hydroxy-α chamigrene and 2, 10-dibromo-3- chloro-ct-chamigrene. Laurencia nipponica can be referred to as a turther chemical race that is char- acterized by the production of two C[sup15] bromoethers, (3E)-taureatin and (3E)-isolaureatin, and a sesqui- terpenoid, 2,10-dibromo-3-chloro-9-hydroxy-a- chamigrene as major compounds. [ABSTRACT FROM AUTHOR]

Laurencia omaezakiana Masuda, sp. nov. (Ceramiales, Rhodophyta) is described from Japan. It is characterized by the following set of features: (I) the production of four periaxial cells from each vegetative axial cell; (ii) a shift in branching from distichous to spiral; (iii) the presence of projecting superficial cortical cells near the apices of branches; (iv) the presence of longitudinally oriented secondary pit-connections between contiguous superficial cortical cells; (v) the presence of lenticular thickenings in the walls of medullary cells; (vi) the occurrence of 1-2 corps en cerise in each superficial cortical cell and a single corps en cerise in each trichoblast cell; and (vii) a parallel arrangement of tetrasporangia. Furthermore, it produces a characteristic triterpenoid (enshuo), which has not been detected in other species of Laurencia, as a major halogenated secondary metabolite. A synoptical key to the 23 species of Laurencia growing in Japan is given. Laurericia ceylanica J. Agardh and Laurencia heterocs'ada Harvey are excluded from the Japanese marine algal flora. The `latter is a distinct species from Laurencia filiformis (C. Agardh) Montagne. [ABSTRACT FROM AUTHOR]

Two populations of the red alga Laurencia majuscula (Harvey) Lucas (Rhodomelaceae, Ceramiales) from Taketomi Island and Hateruma Island, the Ryukyu Islands, Japan, have been characterized on the basis of both morphological features and halogenated Secondary metabolite content. These populations have smaller and more slender thalli than those of other regions. Furthermore, the populations contain two chamigrane-type sesquiterpenoids, (2R,3R,5S)-5- acetoxy-2-bromo-3-chlorochamigra-7( 14),9-then-8- one and (2R,3R)-2-bromo-3-chlorochamigra-7(14). 9-dien-8-one, and a laurane-type sesquiterpenoid, debromoisolaurinterol, as secondary metabolites which are different from those previously reported from other populations. These results are consistent with the concept of 'chemical races' within a single species of Laurencia. [ABSTRACT FROM AUTHOR]

Womersleya monanthos (J. Agardh) Papenfuss is typically an epiphyte of larger brown and red algae that are common iii drift along the southeastern coasts of Australia. A hitherto little-known member of the Phycodrys group of the Nitophylloideae, its reproductive features have been studied in detail and its taxonomic position clarified. Blades are polystromatic throughout and lack veins or nerves, with blades originating from apical cells of primary and second-order cell rows. Intercalary cell divisions take place in primary cell rows and all other branch orders, with third-order laterals arising both abaxially and adaxially on cells of second-order rows. Fertile central cells bear procarps on pericentral cells on both sides of the blade, the procarps consisting of two 4-celled carpogonial branches and a single central group of sterile cells that enlarge and persist at the distal end of a bicanipariulate fusion cell at maturity. Spermatangia and tetrasporangia form in circular subapical son on both sides of the blade or in marginal lobes or proliferations. After comparing it to other members of the Phycodrys group, we conclude that Womersleya is a monotypic genus well distinguished from other genera and with probable closest affinities to the Northern Hemisphere Polyneura. Erythroglossum and SorelIa, as well as the Australian endemic. Crassilingua. [ABSTRACT FROM AUTHOR]

Field and culture samples of the red algal genera Bostrychia and Stictosiphonia from all around the world were analyzed for the polyols D-Sorbitol and dulcitol, that function as osmolytes, as well as for the heteroside digeneaside by using [sup13]C-NMR spectroscopy and HPLC. While all plants exhibited D-sorbitol, the occurrence of dulcitol and digeneaside was highly variable. Therefore, different types of low molecular weight carbohydrate distribution patterns were found in Bostrychia and Stictosiphonia. The presence of D-sorbitol seems to be a reliable chemosystematic character for both genera, because no other red alga is known to contain this compound. The lack of dulcitol may be correlated with the geographical origin of the Bostrychia and Stictosiphonia samples: while all tropical isolates exhibited both sugar alcohols, in cold-temperate plants only D-sorbitol was determined. In warm-temperate species, however, both polyol distribution types may occur. These data are discussed in terms of possible temperature sensitivity of the dulcitol pathway However, the biological function of digeneaside (the main photo-assimilated compound in members of the order Ceramiales) is still obscure. [ABSTRACT FROM AUTHOR]

The binding of FITC labeled lectins to repair cells of Antithamnion nipponicum Yamada et Inagaki and Griffithsia pacifica Kylin, and their physiological effects on somatic cell fusion have been studied. Results indicate that repair cells strongly bind the lectins ConA and LCA, whereas other lectins did not bind to the cell. The binding of these lectins to the dead cell wall shows ConA and LCA specific substances are secreted from the tip of the repair cells. When fluorescently labeled ConA or LCA was added at various time intervals after wounding, it firstly bound (3 h post-wounding) as a thin layer at the tips of the adjacent cells. Later (4-5 h post-wounding) labeling also appeared at the tips of the repair cells. Intense labeling at these sites continued throughout the wound-healing process until repair cell fusion, at which time the lectin labeling was reduced to a narrow ring around the area of fusion. When added to plants prior to wounding and with continued monitoring, these same lectins were found to act as inhibitors to the wound-healing response. Other control lectins showed no inhibitory effects. These results suggest that a signal glycoprotein with α-D-mannosyl residues is involved in the wound-healing process of Antithamnion nipponicum. Lectins conjugated with visible tags can be used as a very fast and useful tool to monitor these signal substances. [ABSTRACT FROM AUTHOR]

Morphological and hybridization experiments were performed on Caloglossa leprieurii (Montagne) J. Agardh collected from Japan, Singapore and Australia in order to evaluate taxonomic characters of this species. Within C. leprieurii at least four mating groups were recognized from the Indo-Pacific region. These mating groups could be characterized by the blade width at the internode and the cell-row numbers on the opposite side derived from the first axial cell at the main axis, though these properties showed a certain variability even in the same plant under both field and culture conditions. The phylogenetic relationship and geographic distribution of the four mating groups are discussed. [ABSTRACT FROM AUTHOR]