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1.
Catherine Riaux‐Gobin Michel Coste Richard W. Jordan Oscar E. Romero René Le Cohu 《Phycological Research》2014,62(3):153-169
During a survey of the coral reef diatoms of Moorea Island (Society Archipelago, South Pacific) a small‐sized member of the order Achnanthales was studied using a light microscope (LM) and a scanning electron microscope (SEM). This marine taxon has: a raphe valve (RV) with a non‐crenulate edge; a high cingulum; a sternum valve (SV) often irregularly striated and areolae with concave hymenate pore occlusion; a thick and plain SV valvocopula (SVVC), ring‐shaped, composed of large fused fimbriae, with a central elliptic foramen bordered by the peg‐like edge of the fimbriae. On abvalvar side, the SVVC bears radiate concave and robust transapical ribs, interlinking with short elevated transverse ribs of the RV valvocopula (RVVC). Large marginal fenestrae of the RVVC give access to pseudoloculi. One oblong, unique and striated papilla is located on each RVVC rib. Given this unique set of features, we describe Xenococconeis opunohusiensis gen. et sp. nov. as a new taxon belonging to the Achnanthales. The characteristics of the new taxon are compared with Campyloneis Grunow and Cocconeis Ehrenberg. From New Caledonia, Cocconeis neocaledonica Maillard ex Lange‐Bertalot et Steindorf, a freshwater diatom, was described with two internal septa with marginal pseudoloculi. Based on subsequent SEM illustrations and remarks, we propose the transfer of C. neocaledonica to the new genus, and compare it to the type species, Xenococconeis opunohusiensis. 相似文献
2.
The primary productivity of two turbid, shallow lakes on the Tasmanian Central Plateau was determined by the C14 technique from half-light day incubations in situ. Graphical integration of depth-rate curves gave estimates of areal day rates of production and of annual rates.The 2 lakes are closely adjacent and very similar physically and chemically, but have very different phytoplankton populations. Lake Crescent has ten times the standing crop biomass of Lake Sorell but its greater turbidity restricts light penetration, and production per unit of surface per day and per year is only 2.6 times that of Sorell.With day rates of 25-(44)-93 mgCm–2 and annual production of 16.9 gCm–2 Lake Sorell could be regarded as oligotrophic. Consideration of standing crop biomass and morphometry however indicates oligo-mesotrophy. Lake Crescent with day rates of 35-(115)-250 mgCm–2 and annual production of 45 gCm–2 is moderately eutrophic.Incubations in constant light demonstrated considerable variation in production rates in different parts of Lake Crescent. 相似文献
3.
A chlorarachniophycean alga, Lotharella amoebiformis, which has been classified in the genus Lotharella is placed into a new genus Amorphochlora gen. nov., based on its phylogenetic position, which has been clarified by the recently accumulated molecular phylogenetic information, and the morphological difference between the vegetative cells of the Lotharella species. Following this taxonomic treatment, a new combination Amorphochlora amoebiformis comb. nov., is proposed. 相似文献
4.
Asteromenia gen. nov. (Rhodymeniales, Rhodophyta) is proposed with a single species, Asteromenia peltata (W. R. Taylor) comb. nov. (basionym: Fauchea peltata W. R. Taylor). Thalli of the proposed new genus are stipitate with dorsiventral, peltate blades that are initially circular in shape but with age become stellate with ligulate arms. Internally, the blades have a polystromatic medulla of large, hyaline cells, grading into a cortex of smaller, pigmented cells. Clusters of translucent cells occur on the dorsal surface of the blade. Tetrasporangia are formed by transformations of intercalary midcortical cells. Mature tetrasporangia have cruciately arranged spores and are densely aggregated in the cortex, mostly on the ventral surface, but occasional tetrasporangia also arise on the dorsal surface. Carpogonial branches are four-celled and arise on inner cortical cells. Auxiliary cells are borne on auxiliary mother cells attached to supporting cells of the carpogonial branches. Cystocarps are protuberant, with well-developed, ostiolate pericarps that often have extended, proboscis-like necks. The new genus differs from the previously described peltate or dorsiventral taxa in the Rhodymeniaceae by its polystromatic medulla (Maripelta and Sciadophycus have a monostromatic medulla), intercalary tetrasporangia formed in an unmodified cortex, and four-celled carpogonial branches (Halichrysis, as typified by H. depressa (J. Agardh) F. Schmitz, has terminal tetrasporangia in nemathecia and three-celled carpogonial branches). 相似文献
5.
Carlos E. M. Bicudo 《Journal of phycology》1976,12(1):22-24
Bipolar asymmetry has been considered a morphological characteristic sufficient for differentiation of genera among the Desmidiaceae. Therefore, Micrasterias sudanensis Grönbl., Prowse & Scott, the only species of Micrasterias showing such asymmetry, is made the type of a new genus, Prescottiella, gen. nov. 相似文献
6.
A new sand‐dwelling dinoflagellate from Palau, Galeidinium rugatum Tamura et Horiguchi gen. et sp. nov., is described. The life cycle of this new alga consists of a dominant nonmotile phase and a brief motile phase. The motile cell transforms itself directly into the nonmotile cell after swimming for a short period, and cell division takes place in the nonmotile phase. The nonmotile cell possesses a dome‐like cell covering, which is wrinkled and equipped with a transverse groove on the surface. The cell has 10–20 chloroplasts and a distinct eyespot. The motile cell is Gymnodinium‐like in shape. The dinoflagellate possesses an endosymbiotic alga to which the chloroplasts belong and which is separated from the host (dinoflagellate) cytoplasm by a unit membrane. The endosymbiont cytoplasm also possesses its own eukaryotic nucleus and mitochondria. The eyespot is surrounded by triple membranes and is located in the host cytoplasm. Photosynthetic pigment analysis, using HPLC, revealed that G. rugatum possesses fucoxanthin as the principal accessory pigment instead of peridinin. The rbcL tree showed that G. rugatum is monophyletic with Durinskia baltica (Levander) Carty et Cox and Kryptoperidinium foliaceum (Stein) Lindemann and that this clade is closely related to the pennate diatom, Cylindrotheca sp. The endosymbiont of G. rugatum is therefore shown to be a diatom. Phylogenetic analysis based on small subunit rDNA sequences demonstrated that G. rugatum, D. baltica, and K. foliaceum, all of which are known to harbor an endosymbiont of diatom origin, are closely related. 相似文献
7.
Akihiro Tuji 《Phycological Research》2002,50(4):313-316
A recent diatom, Aulacoseira nipponica (Skvortzow) Tuji comb. et stat. nov., is described from Lake Biwa, Japan, where they had been identified previously as Aulacoseira solida (Eulenstein) Krammer. These forms are compared with populations of A. solida from North America. The Japanese species differs from the North American specimens in characteristics related to the density of striae and form of the rimoportulae. 相似文献
8.
B.S.C. Leadbeater 《欧洲藻类学杂志》2013,48(1):57-69
A preliminary study of the fine structure of various stages in the life cycle of von Stosch's solate of ‘Syracosphaera carterae’ has been made by means of sections and whole mounts. Protoplast structure appears to be similar throughout the cycle. However, the Apistonema thallus possesses a cell wall composed of numerous layers of closely adpressed rimless unmineralised scales. Two types of asexual swarmers are shown to be covered with one or two layers of somewhat similar scales. One type of swarmer possesses a short haptonema which is covered with small scales. In addition the coccolith-bearing stages are shown to be identical with Hymenomonas carterae sensu Manton and Peterfi (1969) and this isolate has therefore been transferred to H. carterae. 相似文献
9.
Gerald T. Kraft 《Journal of phycology》1975,11(4):399-410
The only member of the red algal family Solieriaceae known from New Zealand is the endemic Sarcodiotheca colensoi (Hook. & Harv.) Kylin. This study shows that it differs in several respects from the type S. furcata (Setch. & Gard.) Kylin; thus a new genus Placentophora is created for the New Zealand alga. Although P. colensoi nov. comb. is retained in the Solieriaceae on the basis of vegetative, spermatangial, tetrasporangial, carpogonial-branch and early gonimoblast features, it differs from typical members of that family in its pattern of later carposporophyte development. After a single gonimoblast initial is cut off from the auxiliary cell towards the center of the thallus, further gonimoblasts develop from the initial as ramifying, radiating filaments. These filaments enter an extensive “nutritive-cell” region surrounding the auxiliary cell, form, numerous connections to the “nutritive” cells, and incorporate most of them into a central placenta of interconnected, and variously-fused vegetative and gonimoblast cells. Carpo-sporangia then form in short chains around the periphery of the placenta. The cystocarp lacks both a central fusion cell and a sterile-celled investment, or “Faserhülle.” The distinctive carposporophyte of Placentophora is compared to patterns of gonimoblast development, known in other members of the Solieriaceae. 相似文献
10.
Surajit Roy Yan Liu John Patrick Kociolek Rex L. Lowe Balasubramanian Karthick 《Phycological Research》2020,68(1):80-89
A new triundulate naviculoid diatom genus is described from the Western Ghats of Peninsular India and Hainan Province, China. The new taxon, Kulikovskiyia gen. nov. has robust conical spines along its margin and at the apices and the external valve face has longitudinally‐oriented siliceous slat system extending the length of the valve. The external distal raphe ends bifurcate and terminates on the valve face. There appear to be superficial similarities between this Asian genus and species and Playaensis, a genus comprised of two species found only in the western USA. The systematic position of Kulikovskiyia is discussed, and other than noting its similarities to other biraphid naviculoid diatoms due to symmetry features and the position of the raphe, we are uncertain about its systematic placement at finer levels of classification. 相似文献
11.
Hiroshi Ito 《Bioscience, biotechnology, and biochemistry》2013,77(5):827-832
The characteristic sweet-aroma components in refinery final molasses were isolated by using a combination of sensory evaluation, column chromatography and gas chromatography, and were identified by infrared spectrometry, mass spectrometry and color reactions. Identified were ethyl n-hexanoate, ethyl phenylacetate, phenylacetic acid, n-butyl benzoate, isopropyl benzoate, l(+)-pantolactone, benzoic acid, o-toluic acid, m-toluic acid, β-phenylpropionic acid, succinic anhydride, maltol, isomaltol, and 2-methyl-5-hydroxy-6-ethyl-γ-pyrone.The aroma of the mixture of these compounds and vanillin and vanillic acid was similar to that of refinery molasses by sensory evaluation. The results indicate that these compounds are important in producing of sweet molasses aroma. 相似文献
12.
《Bioscience, biotechnology, and biochemistry》2013,77(3):419-426
Isolates AH11T and AH13T were isolated from flowers of lantana and candle bush respectively collected in Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates formed an independent cluster, which was then connected to the type strain of Saccharibacter floricola. The calculated pair-wise 16S rRNA gene sequence similarities of isolate AH11T were 95.7–92.3% to the type strains of the type species of the 12 genera of acetic acid bacteria. The DNA base composition was from 51.2 to 56.8 mol % G+C, with a range of 5.6 mol %. When isolate AH11T was labeled, DNA-DNA similarities were 100, 12, 4, 5, and 4% respectively to isolates AH11T and AH13T and the type strains of Saccharibacter floricola, Gluconobacter oxydans, and Acetobacter aceti. The two isolates were non-motile and did not oxidize either acetate or lactate. No growth was found in the presence of 0.35% acetic acid w/v. The two isolates were not osmophilic but osmotolerant, produced 2,5-diketo-D-gluconate from D-glucose, and did not oxidize lactate, thus differing from strains of Saccharibacter floricola, which showed weak lactate oxidation. The two isolates contained unsaturated C18:1ω7c fatty acid as the major fatty acid, and were unique in the presence of a considerable amount of straight-chain C18:12OH fatty acid. Q-10 was present as the major isoprenoid quinone. Neokomagataea gen. nov. was proposed with the two species, Neokomagataea thailandica sp. nov. for isolate AH11T (=BCC 25710 T =NBRC 106555T), which has 56.8 mol % G+C, and Neokomagataea tanensis sp. nov. for isolate AH13T (=BCC 25711T=NBRC 106556T), which has 51.2 mol % G+C. 相似文献
13.
Five Ceramiaceae (Rhodophyta) are reported from the offshore waters of the southeastern, warm temperate coast of the United States. These include two new monotypic genera, Calliclavula trifurcate Schneider in the Griffithsieae and Nwynea grandispora Searles in the Sphondylothamnieae, and three new species, Callithamniella silvae Searles, Ptilothamnion occidentale Searles, and Lejolisia exposita Schneider et Searles. 相似文献
14.
Roh SW Kim KH Nam YD Chang HW Kim MS Shin KS Yoon JH Oh HM Bae JW 《Journal of microbiology (Seoul, Korea)》2008,46(5):594-598
A novel Gram-negative and rod-shaped bacterium, designated N8T, was isolated from tidal flat sediment. Phylogenetic analysis based on 16S rRNA gene sequences showed that N8T strain is associated with the family Phyllobacteriaceae: two uncultured clones (98.4 and 99.8% 16S rRNA gene sequence similarity) and the genus Mesorhizobium (≤97.0%). The novel strain formed a separate clade with uncultured clones in the phylogenetic tree based on 16S rRNA gene
sequences. Cellular fatty acid profiles predominately comprised C18:1
ω7c and C19:0 cyclo ω8c. The major isoprenoid quinone is ubiquinone-10 and genomic DNA G+C content is 53.4 mol%. The polyphasic taxonomic study indicates
that the novel strain N8T represents a novel species of the new genus in the family Phyllobacteriaceae, named Aliihoeflea aestuarii. The type strain is N8T (= KCTC 22052T= JCM 15118T= DSM 19536T). 相似文献
15.
Roberta A. Townsend 《Journal of phycology》1979,15(3):251-259
Synarthrophyton gen. nov. is described based on southern Australian material of Melobesia patena Hooker fils & Harvey, which shows features intermediate between Mesophyllum Lemoine and Lithothamnium Philippi. It has the thin-walled rounded epithallial cells and coaxial hypothallium characteristic of Mesophyllum and the type of procarp and male structures common to Lithothamnium. Synarthrophyton is unique within the subfamily Melobesioideae (J. E. Areschoug) Yendo because it displays secondary pit connections. Details of the vegetative and reproductive morphology of S. patena (Hooker fils. & Harvey) comb. nov. are given and its taxonomic position in the Corallinaceae Lamouroux discussed. 相似文献
16.
Two new propagule-farming red algae from southern Australia, Deucalion levringii (Lindauer) gen. et comb. nov. and Anisoschizus propaguli gen. et sp. nov., are described and defined largely on their development in laboratory culture. Deucalion is included in the tribe Compsothamnieae on the basis of its subapical procarp and alternate distichous branching. It differs from the other genera included in that tribe in that it produces 3-celled propagules, polysporangia, a subapical cell of the fertile axis which bears 3 pericentral cells, and an apparently post-fertilization involucre which develops from the hypogenous and sub-hypogenous cells of the fertile axis. Its gametophyte morphology has been elucidated in culture, as only sporophytes are known from the field. Gametophytes do not appear to produce propagules. Anisoschizus is provisionally included in the tribe Spermothamnieae on the basis of its subdichotomous branching, possession of a prostrate system and the production of polysporangia. It differs from the other genera of the tribe in the production of 2-celled propagules. Observations on the germination of the “monosporangia” of Mazoyerella arachnoidea and Monosporus spp. indicate that they are analagous to the propagules of Deucalion and Anisoschizus. The nature of these propagules and their role in recycling the parent plant are discussed and contrasted with true monosporangia. It is recommended that Monosporus be maintained as a form genus containing representatives from more than one tribe, as exemplified by plants from Lord Howe I. provisionally identified as M. indicus Boergesen which have both prostrate and erect, as opposed to only erect, axes. 相似文献
17.
Liqiong Li Qianqian Zhang Xiaozhong Hu Alan Warren Khaled A.S. Al-Rasheid Abdulaziz A. Al-Khedheiry Weibo Song 《European journal of protistology》2009,45(3):237-248
The morphology and infraciliature of the marine hypotrichous ciliate Nothoholosticha fasciola (Kahl, 1932) nov. gen., nov. comb., isolated from mariculture waters near Qingdao, China, are redescribed based on live and protargol-impregnated specimens. Features reported for the first time include the possession of more than 50 macronuclear nodules and details of the infraciliature, i.e. 50–60 adoral membranelles, shortened paroral and endoral membranes, six frontal, one buccal and two to seven transverse cirri, ca. 40 pairs of midventral cirri, ca. 60–120 left and 70–120 right marginal cirri, three dorsal kineties, caudal and frontoterminal cirri absent. In addition, brief details of two stages of cellular reorganization in N. fasciola are supplied and comparisons with some related urostylids based on SS rRNA gene sequence data are reported. The new genus Nothoholosticha is established based primarily on the absence of frontoterminal cirri, which distinctly separates it from similar urostylid genera. Anteholosticha longissima is transferred to Nothoholosticha as N. longissima (Dragesco and Dragesco-Kernéis, 1986) nov. comb. and Holosticha antarctica is transferred to Pseudokeronopsis as P. antarctica (Wilbert and Song, 2008) nov. comb. 相似文献
18.
On the basis of LM, we isolated strains of two species of fusiform green flagellates that could be assigned to former Chlorogonium (Cg.) Ehrenb. One species, “Cg.”heimii Bourr., lacked a pyrenoid in its vegetative cells and required organic compounds for growth. The other was similar to Cg. elongatum (P. A. Dang.) Francé and “Cg.”acus Nayal, but with slightly smaller vegetative cells. Their molecular phylogeny was also studied based on combined 18S rRNA, RUBISCO LSU (rbcL), and P700 chl a‐apoprotein A2 (psaB) gene sequences. Both species were separated from Chlorogonium emend., Gungnir Nakada and Rusalka Nakada, which were formerly assigned to Chlorogonium. They were accordingly assigned to new genera, Tabris Nakada gen. nov. and Hamakko (Hk.) Nakada gen. nov. as T. heimii (Bourr.) Nakada comb. nov. and Hk. caudatus Nakada sp. nov., respectively. Tabris is differentiated from other genera of fusiform green flagellates by its vegetative cells, which only have two apical contractile vacuoles and lack a pyrenoid in the chloroplast. Hamakko, on the other hand, is distinguishable by the fact that its pyrenoids in vegetative cells are penetrated by flattened thylakoid lamellae. 相似文献
19.
20.
NORMAN D. LEVINE 《The Journal of eukaryotic microbiology》1979,26(4):532-536
SYNOPSIS The following new taxa of septate gregarines are established: METAMERIDAE fam. nov. includes genera Metamera Duke, Deutomera Bhatia & Setna, and Cognettia gen. n., the last with the type and only species C. legeri (Cognetti de Martiis); family GREGARINIDAE Labbé includes Degiustia gen. n. with the type and only species D. hyallela (Batten & DeGiusti); Cirrigregarina gen. n., with the type species C. spissa (Henry) and another species, C. kamenote (Hoshide); and Molluskocystis gen. n., with the type and only species M. pterotracheae (Stuart). Family HIRMOCYSTIDAE (Grassé) includes Arachnocystis gen. n., with the type species A. arachnoidea (Devdhar & Gourishankar) and 3 other species A. nitida (Geus), A. oribatidae (Geus), A. scutovertexi (Erhardová). Family ACTINOCEPHALIDAE (Léger), subfamily Actinocephalinae (Léger), includes Chilogregarina gen. n., with the type species C. striata (Léger & Duboscq) and 3 other species C. brasiliensis (Pinto), C. dujardini (Schneider), and C. stella (Léger). 相似文献