等片藻属几个种的分类学问题研究

本文使用光学显微镜和扫描电子显微镜对等片藻属Diatoma的6个种：冬季等片藻 D·hiemale(Roth)Heib．、巨大等片藻D．maximum(Grun．)Fricke、中型等片藻D．mesodon(Ehr)Kuetz．、念珠状等片藻D．moniliforme Kuetz．、纤细等片藻D. tenue Ag.、等片藻D,vulgare Bory及其下的4个变种作了研究,并讨论了它们的分类学问题。     

芬兰贝氏藻(硅藻门)的超微结构研究

以采集于青海湖的石附生硅藻(芬兰贝氏藻)为样品,用10%的HCl溶液溶解样品中含钙的固体化合物,再加入30% H₂O₂溶液氧化去掉硅藻细胞的有机物质,获得干净的硅藻标本。利用Naphrax^ 封装剂制成永久装片,在光学和电子显微镜下对其形态特征进行了详细研究。结果表明：(1) 在光学显微镜下芬兰贝氏藻具有披针形的壳瓣外形、尖圆的壳面末端和明显伸长的中轴区三个特征。(2) 在扫描电子显微镜下芬兰贝氏藻紧邻中央区的孔纹明显伸长,其长度为2～4个正常孔纹的长度。(3) 通过文献查阅和相似种类的比较发现,同时具有尖圆的末端和明显伸长的紧邻中央区的孔纹是芬兰贝氏藻鉴定的独特性状组合,故芬兰贝氏藻的身份可由此确定。该研究首次报道了芬兰贝氏藻在中国的分布。     

大兴安岭舟形藻科(硅藻门)中国新记录植物

在大兴安岭沼泽硅藻生物多样性的研究过程中,对采自大兴安岭的600余号标本进行了详细的观察,共观察到舟形藻科中国新记录植物10个分类单位,隶属于4个属,其中类缝藻属1种:粗脉肋缝藻;长篦藻属3种:大长篦藻、细尖长篦藻、双型长篦藻;舟形藻属1种:乌普萨拉舟形藻;辐节藻属5种:两头辐节藻、河生辐节藻、细长辐节藻、豆形辐节藻、地中海辐节藻。本文对这些种类的分类学特征及生态分布特点进行了详细的描述。     

新疆菱形藻属和细齿藻属(硅藻门)中国新记录植物

2001年7月至8月、2007年7月分别两次在新疆各地采集硅藻标本,经显微观察,共鉴定出菱形藻属和细齿藻属(硅藻门)中国新记录植物11种1变种,其中菱形藻属9种:额雷菱形藻(Nitzschia eglei Lange-Bertalot)、弯曲菱形藻(N.flexa Schumann)、多样菱形藻(N.diversa Hustedt)、化石菱形藻[N.fossilis (Grunow) Grunow]、吉斯纳菱形藻(N.gessneri Hustedt)、平庸菱形藻(N.inconspicua Grunow)、辐射菱形藻(N.radicula Hustedt)、常见菱形藻(N.solita Hustedt)和粗肋菱形藻(N.valdecostata Lange-Bertalot & Simonsen);细齿藻属2种1变种:科瑞提细齿藻[Denticula creticola (strup) Lange-Bertalot & Krammer]、库津细齿藻汝牧变种(D.kuetzingii var.rumrichae Krammer)和强壮细齿藻[D.valida (Pedicino) Grunow].并对其12种新记录植物的分类学特征进行了详细的描述.     

哈尔滨产几种囊裸藻扫描电镜观察

本文采用扫描电子显微镜对采自哈尔滨市郊的囊裸藻属(Tra-chelomonas)12种5变种进行观察,其中有中国新记录5种3变种,东北新记录5种1变种。文中对每个种进行了形态描述并附有照片,认为应用扫描电子显微镜观察囊壳的表面结构,对此属的系统分类研究有重要意义。     

四川甘孜曲丝藻科硅藻中国新记录

在四川省甘孜藏族自治州进行硅藻多样性调查时,发现了单壳缝目硅藻中国新记录8种1变种(隶属于4属),分别为:原子曲丝藻Achnanthidium atomus Monnier,Lange-Bertalot&Ector、施特劳宾曲丝藻A.straubianum (Lange-Bertalot) Lange-Bertalot、亚显曲丝藻A. pseudoconspicuum (Foged) Jüttner&Cox、半孔曲丝藻A. semiapertum (Guermeur) Andresen,Stoermer&Kreis、阿雷塔斯真卵形藻Eucocconeis aretassii(Manguin) Lange-Bertalot、披针平面藻微小变种Planothidium lanceolatum var. minor Cleve、厄氏平面藻P.oestrupii (Cleve-Euler) Edlund、球囊沙生藻Psammothidium sacculus (Carter) Bukhtiyarova和双生沙生藻P.didymum (Hustedt) Bukhtiyarova&Round。利用光学显微镜(LM)及扫描电镜(SEM)对8种1变种进行观察,并对其形态特征和生境进行了详细描述。     

中国眼裸藻属(Euglenaria)分类学研究

为对眼裸藻属Euglenaria Karnkowska, Linton&Kwiatowski进行分类学修订,研究以采自中国的12株3种眼裸藻属物种为材料,基于形态学和分子生物学手段对眼裸藻属进行系统发育研究,鉴定了3种眼裸藻属物种,分别是尾眼裸藻Euglenaria caudata (Hubner) Karnkowska et Linton、项圈眼裸藻Euglenaria anabaena(Mainx) Karnkowska et Linton和棒形眼裸藻Euglenaria clavata (Skuja) Karnkowska et Linton,提供了它们的形态特征及分子数据。基于最大似然法和贝叶斯法构建了系统发育树,以亲缘关系较近的双鞭藻科Eutreptiaceae Hollande物种为外类群,其余的裸藻类分为扁裸藻科Phacaceae Kim, Triemer&Shin和裸藻科Euglenaceae Dujardin物种两大支,眼裸藻属位于裸藻科分支(0.84/-),共包含28株眼裸藻属物种,主要分为3个小分支,每个小支的支持率均高达99%以上,项圈眼裸藻和尾...     

中国硅藻化石新种和新记录种

在对江汉平原钻孔中的化石硅藻进行鉴定时,发现1个新种类：江汉异极藻（新种）Gomphonema jianghanensis sp.nov.,该种的主要特征为：壳面狭披针形或线性披针形,端部和基部圆形,中轴区窄。中心区宽呈横矩形,在紧靠中心区的一侧具1条很短的线纹,另一侧有时有1条很短的线纹,有时没有线纹,无孤点。壳缝呈直线,在中央区附近略弯向一侧,在极节处折向另一侧。线纹轻微放射状,中部略弯曲,在近顶端处没有线纹,在10μm内,中部具6—13条。长20—30μm,宽4—7μm。4个中国新记录属：楔异极藻属Gomphosphenia Lange-Bertalot、楔月藻属（新记录属）Cymbopleura Krammer、优美藻属Delicata Krammer、尖月藻属Encyonopsis Krammer,8个中国新记录种：微小异极藻Gomphonema minutiforme Lange-Bertalot＆Reichardt、较细楔异极藻Gomphosphenia tenerrima（Hustedt）Reichardt、舌状楔异极藻Gomphosphenia lingulatiforme（Hustedt）Lange-Bertalot、瑞克舟形藻Navicula rakowskae Lange-Bertalot、北方羽纹藻岛屿变种Pinnularia borealis var.islandica Lange-Bertalot,舟形盖斯勒藻Geissleria tectissima（Lange-Bertalot）Lange-Bertalot＆Metaeltin、岩生楔月藻小变种Cymbopleura rupicola var.minor Krammer和法国尖月藻Encyonopsis falaisensis（Grunow）Krammer,1个种的补充说明：中华优美藻Delicata sinensis Krammer ＆ Metzetin。     

中国栅藻属新分类群与新记录

本文报道在安徽发现的栅藻属Scenedesmus的4个新种,2个新变种及4个中国新记录。 4个新种是安徽栅藻S．anhuiensis, 黄山栅藻S．huangshanensis四翼栅藻S. qua-drialatus和芜湖栅藻S．wuhuensis, 2个新变种是角柱栅藻具刺变种S．prismaticus var．spinosus和史密斯栅藻微刺变种S. smithii var．spinulosus;四个中国新记录是具齿栅藻南方变种S. denticulatus var．australis Playfair,角柱栅藻S. prismaticus Bruhl et Biswas,四棘栅藻具齿变种S·quadricauda var．dentatus Deduss和史密斯栅藻S. smithii Teiling。     

青海省异极藻属和桥弯藻属(硅藻门)的新变种

本文对来自青海省异极藻属和桥弯藻属(硅藻门)的三个新变种进行描述,它们是:橄榄异极藻短纹变种(Gomphonema olivaceum (Lyngbye) Kuetzing var. brevistriatum Li Y. L. et Shi, var. nov.);十字异极藻矩形变种(Gomphonema staurophorum (Pant.) Cleve-Euler var oblongum Li Y. L. et Shi, var. nov)和亚贝桥弯藻具点变种(Cymbella yabe Skvortzow var. punctata Li Y. L. et Shi, var. nov).       

STRUCTURE, COMPOSITION AND BIOGENESIS OF PRASINOPHYTE SCALES

The species composition of phytoflagellates in the Salton Sea has recently been the subject of intense investigation as part of an analysis of the Salton Sea ecosystem. The Salton Sea, an inland sea occupying 980 km² in southern California, has become a major stopping point for migratory birds along the Pacific Flyway. The increasing salinity of the sea, currently at 44 gm L⁻¹, and its eutrophic condition (average depth is nine meters, with a high nutrient load contributed by agricultural drainage from the surrounding farmlands) have contributed to a stressed ecosystem. Massive fish kills and bird kills, including such endangered birds as the brown pelican, have become a recurring problem. Although previous investigations have noted the presence of at least two phytoflagellates implicated in fish mortality, little attention has been paid the to the identities of the smaller flagellates observed growing in the sea and their possible contribution to the fish and bird population mortality. Using freshly collected field samples as well as enrichment culture techniques, we report the occurrence of several genera of cryptomonads in the Salton Sea, including representatives from the genera Chroomonas , Hemiselmis , Leucocryptos , Plagioselmis , Storeatula and Teleaulax.     

How diverse are planktonic cryptomonads in Brazil? Advantages and difficulties of a taxonomic-biogeographical approach

We compare ‘temperate data’ with information contained in 49 surveys of cryptomonads from Brazilian tropical regions. These surveys contain a total of 351 records relative to a total of 38 taxa at the species level or below. All taxa were identified using traditional morphological characters visible with the light microscope. Two taxa appear to be new species, and amongst the known species Cryptomonas erosa Ehrenberg is the most frequently recorded one. To date two species of Pseudocryptomonas Bicudo & Tell (all containing multiple photosynthetic endosymbionts/chloroplasts) and the species Cryptomonas brasiliensis Castro, C. Bicudo & D. Bicudo have not been found outside Brazil. With respect to their geographical distribution in Brazilian tropical regions, cryptomonads are better represented in reservoirs and coastal lagoons located in the south-eastern part of the country. Some species appear to be restricted to brackish coastal ecosystems (oligo- to mesohaline and meso- to eutrophic waters). There are only four records of marine cryptomonads. A comparative study of three different kinds of shallow aquatic environments in Brazil – north-eastern reservoirs, a flood-plain Amazonian lake, and brackish lagoons on the south-eastern coast – shows that cryptomonads are to be found constantly, and their species number density, and biomass are generally low (usually <10%) in relation to the other phytoplankton. The case of Plagioselmis Butcher emend. Novarino, Lucas & Morrall, amongst others, exemplifies the great difficulties encountered while attempting to interpret biogeographical information based on light microscopy within the context of a modern systematic and taxonomic framework based on electron microscopy.     

THE EFFECT OF PHOTON IRRADIANCE ON THE BEHAVIORAL ECOLOGY AND POTENTIAL NICHE SEPARATION OF FRESHWATER PHYTOPLANKTONIC FLAGELLATES1

Photoresponsive behavior in phytoplanktonic flagellates potentially controls depth regulation, vertical migration, and the accumulation of cells in preferred conditions and hence has major implications for photosynthesis, growth, and species competition. This study used microscale laboratory chambers with cell track analysis and mesoscale lake studies to investigate the responses of five phylogenetically contrasting freshwater flagellates to gradients of light. Laboratory results demonstrated that these species differed in their light preferences despite being grown at the same photon irradiance. Preferred photon irradiances were 20–120, 20, 65–120, 4–20, and>200 μmol photons·m^?2·s^?1, respectively, for Ceratium furcoides (Levander) Langhans, Chlamydomonas moewusii Gerloff, Dinobryon sertularia Ehrenberg, Euglena gracilis Klebs, and Plagioselmis nannoplanctica (Skuja) Novarino. Analysis of the response of individual cells showed that in all species, photoresponsive preference was the result of positive and negative phototaxis combined with step‐up and step‐down photophobic reactions. There was no evidence for photokinesis or cell memory. Only in C. furcoides did the preferred photon irradiance alter with growth conditions. In C. furcoides, D. sertularia, and P. nannoplanctica, irradiance preference matched the optimal irradiance for growth, whereas in the two remaining species a lower than optimal irradiance was preferred, suggesting that light may be used as an indicator of other ecological conditions. Mesoscale experiments in a lake demonstrated that the laboratory microscale measurements provide information relevant to understanding ecological distributions. Behavioral responses to light contribute to the delineation of vertical niche separation and provide a method for predicting the spatial and temporal distribution of flagellates.     

Observations on some new and interesting Cryptophyceae

Three new varieties and two new combinations of marine Cryptophyceae are described: Proteomonas pseudobaltica comb, nov., P. pseudobaltica var. leonardiana var. nov., Pyrenomonas salina var. curvata var. nov., Rhinomonas reticulata var. atrorosea comb, et stat. nov., and R. reticulata var. compressa var. nov. Proteomonas is compared to the freshwater Cryptomonas marssonii. Planktonic specimens collected from the southern North Sea during the NERC North Sea Project 1988/89, tentatively identified as Cryptomonas acuta and Plagioselmis sp., are also examined. Characters having taxonomic significance at various levels include cell compression, periplast features, chloroplast number, nucleomorph position, and phycoerythrin type. Comments are made on cell shrinkage occuring during preparation for scanning electron microscopy (up to about 23%). The appearance af trie vestibular region from which the flagella emerge is also discussed. It is suggested that the term 'furrow' may encompass a variety of structures. Of these, only one appears to be non-artefactual; this seems to be taxonomically significant at most at the species level.     

Effects of fish introduction on the length of the tail of cryptomonads in mesocosm experiments

Two different morphs of the small cryptomonad, Plagioselmis prolonga var. nordica with a posterior tail, were observed during summer and fall in the hypertrophic lake, Lake Kasumigaura, Japan. The tail shortened in mesocosms stocked with planktivorous silver carp ( Hypophthalmichthys molitrix Val.) and elongated by more than 50% in mesocosms from which silver carp were removed. The density of Plagioselmis cells increased significantly upon fish stocking and decreased upon fish removal. The tail length was negatively correlated with algal abundance and positively correlated with crustacean densities, but there was no correlation with nutrient levels or physical environmental parameters in the mesocosms. The variation in tail length was induced by the presence/absence of fish, but was not related to their density. However, silver carp manipulation strongly affected the density of the majority of zooplankters and, interestingly, there was a strong correlation between zooplankton density and tail-length change in Plagioselmis. We propose a possible herbivore-induced defense mechanism triggered by the top predator, silver carp.     

Application of the microalga Plagioselmis prolonga for the assessment of water quality in the Amursky and Nakhodka Bays (Sea of Japan)

Based on biotesting, we carried out an estimation of the water quality in the Amursky and Nakhodka Bays (Sea of Japan) using Plagioselmis prolonga (Cryptophyta). The obtained data were compared with the data from water biotesting using Dunaliella salina (Chlorophyta). It was shown that water from the Amursky Bay produced more a negative effect on both microalgae than water from the Nakhodka Bay. It was established that sensitivity of the P. prolonga microalga exceeded that of D. salina. This was confirmed by a sharp decrease of the P. prolonga motile cell number in the studied water.     

海南岛淡水单壳缝类硅藻的分类学研究

对采自海南岛的淡水硅藻进行了分类学研究,共观察到曲壳类硅藻40个分类单位。其中11个分类单位为中国新记录,分别为岛曲壳藻Achnanthes islandica、阿奇长曲壳藻Achnanthidium archibaldianum、高尔夫长曲壳藻Achnanthidium caledonicum、弯曲长曲壳藻Achnanthidium deflexum、河流长曲壳藻Achnanthidium rivulare、极常见平面藻Planothidium frequentissimum、皮亚夫平面藻Planothidium piaficum、短肋片状藻Platessa brevicostata、胡斯特片状藻Platessa hustedtii、山地片状藻热带变种Platessa montana var.tropica、扁圆卵形藻尖细变种Cocconeis placentula var.acuta。文章对这11个分类单位的形态特征及生境分布特点进行了描述,讨论了同相近种类的区别特征。对片状藻属Platessa的分类特征进行了中文描述。     

Hemiselmis andersenii and Chlorella stigmatophora As New Sources of High-value Compounds: A Lipidomic Approach

To unlock the potential of Chlorella stigmatophora (Trebouxiophyceae, Chlorophyta) and Hemiselmis andersenii (Cryptophyceae, Cryptophyta) as natural reactors for biotechnological exploitation, their lipophilic extracts were characterized using Fourier Transform Infrared spectroscopy with Attenuated Total Reflectance (FTIR-ATR) and Gas Chromatography-Mass Spectrometry (GC-MS) before and after alkaline hydrolysis. The GC-MS analysis enabled the identification of 62 metabolites—namely fatty acids (27), aliphatic alcohols (17), monoglycerides (7), sterols (4), and other compounds (7). After alkaline hydrolysis, monounsaturated fatty acids increased by as much as 87%, suggesting that the esterified compounds were mainly neutral lipids. Hemiselmis andersenii yielded the highest Σω3/Σω6 ratio (7.26), indicating that it is a good source of ω3 fatty acids, in comparison to C. stigmatophora (Σω3/Σω6 = 1.24). Both microalgae presented significant amounts of aliphatic alcohols (6.81–10.95 mg · g dw⁻¹), which are recognized by their cholesterol-lowering properties. The multivariate analysis allowed visualization of the chemical divergence among H. andersenii lipophilic extracts before and after alkaline hydrolysis, as well as species-specific differences. Chlorella stigmatophora showed to be a valuable source of essential fatty acids for nutraceuticals, whereas H. andersenii, due to its high chemical diversity, seems to be suitable for different fields of application.     

Cyst‐theca relationship of a new dinoflagellate with a spiny round brown cyst,Protoperidinium lewisiae sp. nov., and its comparison to the cyst of Oblea acanthocysta

Round spiny brown cysts with apiculocavate processes were isolated from sediments of Lake Saroma, Japan, Changle Harbor, East China Sea, China, Jinzhou Harbor, Bohai Sea, China, and San Pedro Harbor, California, USA. Superficially similar round spiny brown cysts of the species, Oblea acanthocysta were, for comparison, restudied through light microscopy and scanning electron microscopy (SEM) and by sequencing of small subunit (SSU) and large subunit (LSU) rDNA obtained through a single cyst from Lake Saroma. These morphological measurements and SEM observations showed that the new cysts can be discriminated from O. acanthocysta by the archeopyle, number of processes, shape of process bases and its apiculocavate processes. Based on LSU sequences, the most closely related species was Protoperidinium monovelum, for which no cyst stage has been described so far. However, the thecal morphology of the specimens found in this study differed from P. monovelum in details of the sulcal plates and shape of apical pore and 2a plate. We therefore describe Protoperidinium lewisiae sp. nov., which can be found in estuarine subtropical to temperate waters of the Pacific Ocean.     

MOLECULAR PHYLOGENY OF PHYCOCYANIN‐CONTAINING CRYPTOPHYTES: EVOLUTION OF BILIPROTEINS AND GEOGRAPHICAL DISTRIBUTION1

Of 34 strains assigned to the cryptophyte genera Chroomonas Hansg., Hemiselmis Parke, and Komma D. R. A. Hill, distribution patterns of biliproteins, habitats, and sampling sites across a phylogenetic tree have been examined. The combined data set assembled from nuclear SSU rDNA, partial nuclear LSU rDNA, and nucleomorph SSU rDNA sequences comprised 4,083 positions and yielded an almost completely resolved tree. Spectrophotometry of the biliproteins and mapping of the different types of biliproteins onto the phylogenetic tree unveiled a complex evolutionary history. Different from other cryptophyte clades, the types of biliproteins were not generally congruent with clades or subclades of the genera Chroomonas (paraphyletic, phycocyanins [PCs] 645 or 630), Hemiselmis (PCs 612, 630 or phycoerythrin [PE] 555), and Komma (PC 645). At least one putative character reversal took place in the genus Chroomonas. Several changes in biliproteins have been found in the genus Hemiselmis, including two new biliprotein variants that probably originated by slight modifications from PC 612 and PE 555, respectively (PC 577 and PE 545/555). Freshwater and marine/brackish taxa were intermingled across the tree without displaying a specific pattern. In four terminal clades, genetically identical strains have been found to occur both in Europe and in the USA. The Chroomonas/Hemiselmis/Komma clade proved to be the most diverse of all cryptophyte clades concerning types of biliproteins and distribution of clades across marine or freshwater habitats.