东海陆架盆地西南部始新世海相沟鞭藻类

本文描述了东海陆架盆地西南部W6-1-1井始新世海相沟鞭藻类24属36种(包括4新种),绿藻1属2种;论述了生物地层特征,建立了两个沟鞭藻组合并讨论了其地质时代、古环境及海侵海退等问题。东海陆架盆地始新统两个沟鞭藻组合基本上代表了一个大的海侵海退过程;海侵导致微体浮游植物的繁盛,并提供了较丰富的生油母质。文中提出下、中始新统的界线应置于温州组下部的灰岩与厚层泥岩之间,即瓯江组上部至温州组下部的灰岩应划归下始新统,温州组的其余地层应划归中始新统。     

山东东营凹陷晚更新世海相沟鞭藻类

本文首次描述山东东营凹陷晚更新世海侵层中的沟鞭藻类化石12种含1亚种1比较种和1新种(Dissiliodinium tuberculatum sp．nov．),归属于6属3科;简要介绍了沟鞭藻组合特征。     

南极洲早第三纪的沟鞭藻

本文研究的标本是我国南极洲考察队采自南极半岛北端,同层标本中含有可见于白垩纪至中始新世的双壳类化石Aphrodina sp.,据所含沟鞭藻和孢粉化石的研究,其时代为始新世。文中对13属15种包括4未定种1个新种的沟鞭藻进行了描述,并根据沟鞭藻组合的成分分析,对古地理、古气候、古生态进行了初步探讨。     

海南乐东鹿母湾组沟鞭藻和疑源类及其沉积环境

海南乐东洪帽剖面鹿母湾组中,首次发现丰富的由沟鞭藻和疑源类组成的浮游微体植物群,共计10属25种(沟鞭藻6属20种,包括1新种。疑源类4属5种),组成以Laciniadinium granulatum-Granodiscus granulatus为特征的藻类组合。根据组合中主要属种的生长环境,认为海南乐东鹿母湾组沉积时期主要为干旱的热带(或亚热带)气候环境;有些海相沟鞭藻的发现,不能完全排除鹿母湾组沉积受弱海水的影响,水域较平静。     

甘肃玉门红柳峡早白垩世下沟组的介形类

本文描述了甘肃玉门红柳峡下沟组的介形类化石共5属4亚属、13种。其中1新属、6个新种、1个比较种。根据介形类特征和地理分布,推测下沟组的时代为早白垩世巴列姆期;同时结合玉门红柳峡下沟组的岩性特征,认为该组为淡水微咸水河湖相沉积。     

台湾海峡中北部陆架区表层沉积的近代沟鞭藻囊孢组合及其环境意义

文中研究台湾海峡中北部大陆架区表层沉积的近代沟鞭藻囊孢组合特征及其与海区环境的关系。沟鞭藻囊孢组合由膝沟藻类和多甲藻类的12属19种和裸沟藻类的一个未定囊孢属种组成,还包含丰富或较丰富的微体有孔虫壳体内膜。该组合代表一种适应温暖内浅海环境的沟鞭藻生物群落。文中还对首次在我国发表的沟鞭藻囊孢种进行了描述。     

南海北部琼东南盆地渐新世-上新世沟鞭藻指示的沉积环境北大核心CSCD

通过对南海北部琼东南盆地渐新世—上新世3个钻井剖面412个沟鞭藻样品的系统分析,发现了较丰富的沟鞭藻化石。根据沟鞭藻化石丰度、分异度变化以及特征性的环境指示种,对琼东南盆地渐新世至上新世的沉积环境进行了详细研究。认为研究区从早渐新世早期海水开始入侵,至早渐新世晚期海侵范围进一步扩大,一直持续到晚渐新世;早中新世沟鞭藻化石数量和种类明显出现低谷,发生了一次较为明显的海退;中中新世至晚中新世,沟鞭藻化石较丰富,丰度和分异度增加,海水明显比早中新世沉积时期加深;早上新世早期,指示海侵的化石属种较丰富,反映了温暖浅海的沉积环境;早上新世晚期,指示一种开阔的海洋环境,水体较深;晚上新世早期,沟鞭藻化石属种面貌反映了热带浅海环境,但水体可能比早上新世晚期沉积时要浅;晚上新世晚期,指示海侵的沟鞭藻化石属种达到最繁盛时期,海侵范围进一步扩大。     

南海北部琼东南盆地渐新世—上新世沟鞭藻指示的沉积环境

通过对南海北部琼东南盆地渐新世—上新世3个钻井剖面412个沟鞭藻样品的系统分析,发现了较丰富的沟鞭藻化石。根据沟鞭藻化石丰度、分异度变化以及特征性的环境指示种,对琼东南盆地渐新世至上新世的沉积环境进行了详细研究。认为研究区从早渐新世早期海水开始入侵,至早渐新世晚期海侵范围进一步扩大,一直持续到晚渐新世;早中新世沟鞭藻化石数量和种类明显出现低谷,发生了一次较为明显的海退;中中新世至晚中新世,沟鞭藻化石较丰富,丰度和分异度增加,海水明显比早中新世沉积时期加深;早上新世早期,指示海侵的化石属种较丰富,反映了温暖浅海的沉积环境;早上新世晚期,指示一种开阔的海洋环境,水体较深;晚上新世早期,沟鞭藻化石属种面貌反映了热带浅海环境,但水体可能比早上新世晚期沉积时要浅;晚上新世晚期,指示海侵的沟鞭藻化石属种达到最繁盛时期,海侵范围进一步扩大。     

内蒙古二连盆地早白垩世微体浮游藻类

记述了二连盆地东北部早白垩世微体浮游藻类16属28种,分属于沟鞭藻类8属15种,含3新种：Fromeacirculatasp.nov,Nyktericystatrigonasp.nov.,Paucibucinapylophorasp.nov,绿藻3属6种,疑源类4属6种,含2新种：Porusphaeraerenensissn．nov,P．pylophorasp．nov,及黄藻1属1种。可将它们划分为2个组合：赛汉塔拉组三段的Parabohaidina－Fromea-Nyktericysta-Vesperopsis组合（即组合1）和哈达图组的Porusphaeraerenensis组合（即组合2）。较详细地讨论了它们的沉积环境和含沟鞭藻类层段的地质时代,认为赛汉塔拉组三段和哈达图组的时代为早白垩世中晚期,其中赛汉塔拉组三段可能为Barremian期;两个浮游藻类组合反映了较复杂的非海相流积环境,以为鞭藻类占优势的第一组合反映在赛三段沉积时是以半咸水一微咸水为主的湖相环境,以疑源类和绿藻占优势的第二组合反映哈达图组是以淡水为主的湖相沉积。     

新疆塔里木盆地西部晚白垩世—始新世微体浮游植物的几个新属

新疆塔里木盆地西部晚白垩世一始新世海相地层分布广泛,微体浮游植物发育,仅乌恰县巴什布拉克剖面,此次采获分析出沟鞭藻类、绿藻和疑源类等化石就达百余属三百多种。本文所描述的材料,主要是从该剖面及其附近的魔鬼沟剖面乌依塔克组(土伦—森诺期的早期)、齐姆根组下段(古新世)、乌拉根组(中始新世)和巴什布拉克组下段上部(晚始新世)中分析出来的,此外,还有少数标本采自乌恰县乌鲁克恰提和莎车县阿尔塔什剖面,计沟鞭藻类5新属、5新种和绿藻1新属、1新种。文中插图由徐宝瑞同志清绘,笔者谨此致谢。     

Some New Taxa and New Records of Scenedesmus from China

Anhui Province is situated in the subtropical and temperate zones. With favorable climate this district is rich in algae. During 1982-1986, the author made a number of collections of the algal specimens-about 1000 samples from 36 counties and cities of the province. The identification result shows that there are about 30 species and 15 varieties of Scenedesmus in the province. In present paper, however, reported are only some new taxa and new records of Scenedesmus. The 4 new species are Scenedesmus anhuiensis, S. huangshanensis, S. quadrialatus and S. wuhuensis, the 2 new varieties are Scenedesmus prismaticus var. spinosus and S. smithii var. spinulosus, and the 4 new records of distribution in China are Scenedesmus denticulatus var. australis Playfair, S. prismaticus Bruhl et Biswas, S. quadricauda var. dentatus Dedussand S. smithii Teiling.     

内蒙古海拉尔盆地白垩纪生物地层研究进展

兴安岭群龙江组产Ephemeropsistrisetalis等热河生物群分子,九峰山组产富含Cicatricosisporites,Pilosisporites,Concavissimisporites的孢粉组合,兴安岭群龙江组、甘河组火山岩同位素年龄为105-141Ma,证实兴安岭群的时代为早白垩世早期;扎赉诺尔群中以Cypridea,Limnocypridea,Ilyocyprimorpha和Hailaeria等属为代表的介形类动物群,以Nyktericysta,Vesperopsis等属为代表的NV浮游植物群,以富含Lygopodiaceae科各属孢子,尤其是Cicatricosisporites高含量的孢粉组合,代表了中国北方早白垩世特有的动、植物群面貌,而其中Asteropollis,Tricolpites和Polyporites等被子植物花粉化石的发现,这一事实似乎暗示了扎赉诺尔群的时代为早白垩世中、晚期;青元岗组产以Talicypridea,Altanicypris,Chinocypridea和Harbinia为代表的介形类动物群,具有显著的地域性特点,可与松辽盆地四方台组对比,其时代为晚白垩世Maastrichtian期。     

Fatty acid profiling and molecular characterization of some freshwater microalgae from India with potential for biodiesel production

We determined the fatty acid compositions of six species of freshwater microalgae belonging to the Chlorophyta, which were isolated from freshwater bodies in Assam, India. All six microalgae -Desmodesmus sp. DRLMA7, Desmodesmus elegans DRLMA13, Scenedesmus sp. DRLMA5, Scenedesmus sp. DRLMA9 Chlorella sp. DRLMA3 and Chlorococcum macrostigmatum DRLMA12-showed similar fatty acid profiles 16:0, 16:4, 18:1, 18:2, and 18:3 as major components. We also compared fatty acid compositions during the late exponential and stationary growth phases of D. elegans DRLMA13 and Scenedesmus sp. DRLMA9 in BG11 medium. We observed enhanced percentages of total saturated and monounsaturated fatty acids with a concomitant decrease in polyunsaturated fatty acid content upon the prolonged cultivation of both microalgae. Distinct morphological features of microalgal isolates were determined by scanning electron microscopic (SEM) studies. An ornamented cell wall was found in D. elegans DRLMA13, which is characteristic of small spineless species of Desmodesmus. The isolated microalgae were further distinguished through analysis of internal transcribed spacer 2 (ITS2) secondary structures and compensatory base changes (CBCs). Analysis of CBCs showed the relatedness of Chlorella sp. DRLMA3 with other Chlorella-like organisms, but it does not belong to the clade comprising Chlorella sensu stricto, which includes Chlorella vulgaris. The CBC count between Scenedesmus sp. DRLMA9 and other species of Scenedesmus provides evidence that this isolate represents a new species.     

Discovery of Algal Fossils from the Hailar Basin and Its Significance

This article reports Chlorococcalean algae fossil in Member 2 of Damoguaihe Formation, Well Haican-5, South of Hailar Basin. They are Pediastrum simplex, P. boryanum, Scenedesmus cf. bijuga, S. cf. dimorphus, S. beierensis sp. nov.     

Phylogenetic Relationships of Scenedesmus and Scenedesmus-like Coccoid Green Algae as Inferred from ITS-2 rDNA Sequence Comparisons

Abstract: Analyses of ITS-2 ribosomal DNA from Scenedesmus and Scenedesmus-like strains showed that this molecule is well suited for resolving evolutionary relationships at various taxo-nomic levels. The analyses clearly suggested the separation of the investigated strains into two groups which corresponded to the "subgenera" Desmodesmus and Scenedesmus/Acutodesmus . No clear distinction between Acutodesmus and Scenedesmus was seen. It is proposed to regard both groups as distinct genera, Desmodesmus gen. nov. and Scenedesmus sensu strictu , and to merge Acutodesmus into Scenedesmus . Monophyly of both genera, Scenedesmus and Desmodesmus , is further supported by certain secondary structure features of ITS-2. The relationships resolved by the ITS-2 analyses are congruent with findings from cell wall ultrastructure, but not with those from other morphological features such as cell wall surface structures or cell shape. Didymocystis inermis and Dicloster acuatus , though somewhat similar in vegetative cell morphology to species of Scenedesmus and Desmodesmus , were seen as members of independent genera because of substantial differences in primary structure and length variations in ITS-2 when compared with each other and the latter two genera.     

Length–weight relationships of 10 fish species from a Ganga River Basin tributary,Uttarakhand, India

Length‐weight relationships (LWRs) are described for 10 fish species belonging to three families from the Gaula River, a tributary of the Ganga River Basin in India. LWRs for these species were unknown to FishBase, and new maximum lengths are recorded for one species. These results will be useful for fishery research, management and conservation in the least‐explored tributary of the Ganga River Basin.     

垣曲盆地新发现的始爪兽类化石

记述了在垣曲盆地始新世地层两个层位中发现的始爪兽科化石 3个种 ,其中包括 1个新种———周氏路南兽 (Lunaniazhouisp .nov .)。新种与属型种杨氏路南兽不同在于个体小、齿冠低、下前尖和下前脊及下斜脊更退化。     

Length–weight relationships of fish species from Lower Paranapanema River Basin,Upper Paraná River Basin,Brazil

Length–weight relationships were estimated for six fish species occurring in direct tributaries of the Lower Paranapanema River Basin. Data is described for the first time for five species and new measurements are provided for one species in the FishBase database. Studies of fish diversity are critical for species management and conservation, especially in this basin, which has suffered from many anthropical impacts.     

Taxonomic remarks concerning ostracods of the Ponto–Caspian Basin

Taxonomic revision of ostracods of the Pliocene–Pleistocene beds of the Caspian Basin from collections of the VNIGRI and analysis of published data on ostracods of the Ponto–Caspian Sea results in synonymization of 16 species names; one species is provided with a new combination, 40 identifications are improved, and 12 erroneous spellings of ostracod names by certain authors are revealed.