罗马尼亚特提斯区的早白垩世粗枝藻化石(英文)

本文对藻类 Seloporella属的系统分类进行了评论。根据 Barattolo等人 ,1992年对该属的评论 ,结合对产自罗马尼亚阿朴塞尼山区 ( Apuseni Mountains) ,早白垩世的 Triploporella neocomiensis Radoicˇ ic′及与己发表的资料进行了对比研究 ,提出了 Seliporella neocomiensis的新组合 ,同时与该化石组合形态非常相似的“Diplopora”john-soni Praturlon,1964进行了对比     

河南义马地区晚三叠世—侏罗纪孢粉组合及其地质意义

重点讨论了谭庄组上段孢粉组合（包括１新种和１新组合）；简要描述了侏罗纪义马组砾岩段孢粉组合。谭庄组上段的孢粉组合主要以具双气囊的松柏类花粉为优势（占孢粉总数的６５％），同时又具许多晚三叠世的常见分子和孑遗分子Ａｒａｔｒｉｓｐｏｒｉｔｅｓ，Ｃｕｎｅｉｓｐｏｒｉｔｅｓ，Ｔａｅｎｉａｓｐｏｒｉｔｅｓ。该组合可与中国北方及欧洲晚三叠世孢粉组合进行对比。义马组砾岩段的孢粉组合系首次发现，以蕨类孢子为主（占孢粉总数６２．９％），裸子植物花粉次之（占孢粉总数３７％）。其中常见的类型为Ｃｌａｓｓｏｐｏｌｌｉｓ，其时代为早侏罗世。     

贵州黄花冲下奥陶统湄潭组疑源类

对贵州黄花冲奥陶系湄潭组Azygograptus suecicus带疑源类组合研究表明,该组合可以与扬子区陕南、川东南、黔北、黔南、湘西、鄂西等地同期组合对比,并根据特征分子产出判别该组合应划归环冈瓦纳疑源类生物地理区。鄂西宜昌大湾组疑源类组合与黄花冲湄潭组疑源类组合的差异系环境因素所致。     

山东平邑盆地古新世孢粉组合及其古气候意义

本文对山东平邑盆地卞桥镇国泰庄西ZK101井卞桥组二段的21块井壁岩芯样品进行分析,在其中5块样品中发现了大量保存较好的孢粉和一些淡水藻类化石,总计60属2亚属63种及部分未定种。据此建立了一个孢粉组合,即Pterisisporites-Ephedripites-Ulmaceae组合。该组合以凤尾蕨科和麻黄科花粉占优势,榆科有一定含量为其主要特征,并通过对一些重要分子的地质时代分布及与邻区相关孢粉组合进行对比,确定了其时代为古新世,同时讨论了该孢粉植物群所反映的古气候特点。     

河南伊川盆地晚三叠世大孢子化石

河南伊川盆地屯2井、屯3井谭庄组、椿树腰组产以Hughesisporites gibbosus,Triletes vulgaris占优势的大孢子化石组合。该组合面貌显示其赋存地层的时代为晚三叠世,层位或可与新疆准噶尔盆地、塔里木盆地的黄山街组对比。大孢子化石组合的发现对整个洛阳-伊川地区探井地层划分、对比具有重要意义。     

斑鳞鱼化石的研究引起学术界的关注

最近，中国科学院古脊椎动物与古人类研究所朱敏博士等对发现于云南曲靖的一种原始硬骨鱼──斑鳞鱼（Ｐｓａｒｏｌｅｐｉｓ）进行了细致研究。１９９９年２月１８日出版的英国《Ｎａｔｕｒｅ》杂志报道了他们的研究成果。同期发表的Ｐ．Ｅ．Ａｈｌｂｅｒｇ博士的评论文章认为：“斑鳞鱼具有意想不到的特征组合，将促使我们重新审视脊椎动物进化树；该鱼的发现对‘辐鳍鱼类’和‘肉鳍鱼类’的传统定义提出了质疑，这将对硬骨鱼类进化模式的解释产生重大影响”。在生命史中，硬骨鱼类的起源无疑是一次非常重大的事件。然而，由于化石材料的缺…     

贵州贵定长兴阶的腕足动物群

对贵州省贵定地区长兴期腕足动物群进行了系统研究，建立了该地区长兴阶的４个腕足动物组合，并对各个组合的古生态特征进行了初步探讨。描述了腕足动物化石８属９种，其中２新属７新种。     

新疆塔里木盆地中侏罗世塔尔尕组孢粉植物群及地层和古地理意义

新疆塔里木盆地侏罗系分布广泛,在库车凹陷和塔西南区发育最好。目前对库车凹陷的三叠纪和侏罗纪孢粉植物群研究较为深入,而对塔西南区侏罗纪孢粉化石专题研究不多,尚未建立孢粉组合。作者基于塔西南区乌恰中侏罗统塔尔尕组发现的孢子花粉33属48种的研究,建立了塔尔尕组孢粉组合。该组合以掌鳞杉科花粉Classopollis的优势和真蕨目桫椤科孢子Cyathidites的繁盛为特征,并含有丰富多样且颇具侏罗纪色彩的孢子花粉化石类型。该组合与西欧和俄罗斯巴柔期至巴通期孢粉组合以及北美和澳大利亚巴柔期至卡洛夫期孢粉组合可以进行对比;与我国新疆库车恰克马克组、陕西延安直罗组和湖北兴山沙溪庙组等孢粉组合也可对比。根据孢粉学证据,塔尔尕组的时代应属于中侏罗世晚期(巴通期至卡洛夫期)。当前孢粉植物群支持我国侏罗纪南北植物地理区系之西端分界之划分方案,即塔西南乌恰处于界线以南,而库车处于分界以北。     

宁夏六盘山盆地晚三叠世孢粉组合及其地层意义

对宁夏六盘山盆地炭山、窑山及上流水等３条剖面中原划为中侏罗统延安组下部含煤地层的２１块岩样进行了孢粉分析,获得丰富的孢粉化石,鉴定出７６属１４４种,建立了Ｄｉｃｔｙｏｐｈｙｌｌｉｄｉｔｅｓ－Ａｒａｔｒｉｓｐｏｒｉｔｅｓ－Ｃｙｃａｄｏｐｉｔｅｓ组合。通过与国内外相关孢粉组合对比,认为该组合地质时代应属晚三叠世。首次以孢粉化石为依据,确认了六盘山盆地上三叠统延长组的存在。     

西藏岗巴地区始新世介形虫化石组合

对西藏岗巴盆地层位最高的海相地层——遮普惹组所含介形虫化石进行了分析和研究,共鉴定出22属、33种,建立两个介形虫组合：Paracypris mayaensis sp. nov.-Bairdia zongpuxiensis sp. nov. 组合(下部)和 Phlyctenophora zongpuensis-Semicytherura subsyrnmetros组合(上部);讨论介形虫组合的特征及其地质时代,并与世界上其它地区有关地层进行对比,结合与之共生的有孔虫组合的时代特征,认为含该介形虫组合的海相地层——遮普惹组的时代应为始新世Ypresian-Priabonian早期。描述6种,其中有2新种：Paracypris mayaensis sp. nov.和Bairdia zongpuxiensis sp. nov.。     

Haslea salstonica sp. nov. and Haslea pseudostrearia sp. nov. (Bacillariophyta), two new epibenthic diatoms from the Kingsbridge estuary, United Kingdom

Two new diatom species, Haslea salstonica and Haslea pseudostrearia are described in light and electron microscopy and compared with two well-known members of Haslea. Scanning electron microscope observations confirm that the new species belong to the genus Haslea. This study extends previous observations on the genus, particularly with respect to the development of a pseudostauros. The characteristic features of the genus are discussed briefly.     

14种剑蕨属植物的孢子形态特征及其系统分类学意义

利用扫描电子显微镜对水龙骨科(Polypodiaceae)剑蕨属(Loxogramme)14种植物的孢子形态和表面纹饰进行了观察。结果显示:剑蕨属的孢子具有单裂缝和三裂缝两种类型,个别物种具有中间过渡类型。剑蕨属的孢子纹饰为蠕虫状或浅波纹状。经比较发现,具三裂缝孢子的物种通常植株较小,而具单裂缝的种类则通常植株较大。从进化的角度来看,三裂缝孢子为原始类型,单裂缝孢子为进化类型,因而从孢子形态特征的角度支持剑蕨属为水龙骨科基部类群。     

Ecological importance of sedges: a survey of the Australasian Cyperaceae genus Lepidosperma

Background

Sedges (Cyperaceae) form an important ecological component of many ecosystems around the world. Sword and rapier sedges (genus Lepidosperma) are common and widespread components of the southern Australian and New Zealand floras, also occurring in New Caledonia, West Papua, Borneo, Malaysia and southern China. Sedge ecology is seldom studied and no comprehensive review of sedge ecology exists. Lepidosperma is unusual in the Cyperaceae with the majority of species occurring in dryland habitats.

Scope

Extensive review of ecological literature and field observations shows Lepidosperma species to be important components of many ecosystems, often dominating understorey and sedge-rich communities. For the first time, a detailed ecological review of a Cyperaceae genus is presented.

Conclusions Lepidosperma

species are long-lived perennials with significant abundance and persistence in the landscape. Speciation patterns in the genus are of considerable interest due to complex biogeographical patterns and a high degree of habitat specificity. Potential benefits exist for medicinal products identified from several Lepidosperma species. Over 178 organisms, including 26 mammals, 42 birds, six reptiles, five amphibians, eight arachnids, 75 insects, three crustaceans and 13 fungi, are found to be dependent on, or making use of, Lepidosperma species. A significant relationship exists between Lepidosperma species and the moth genus Elachista. Implications for the conservation and ecology of both sedges and associated species are discussed.     

Multilevel subdivision in the <Emphasis Type="Italic">araneus</Emphasis> species group of the genus <Emphasis Type="Italic">Sorex</Emphasis>: 1. Chromosomal differentiation

This review summarizes the available data on multilevel differentiation in the araneus species group of the genus Sorex (Eulipotyphla, Mammalia). Communication 1 gives basic information about the biology and morphological and karyotypic differentiation of some species belonging to this genus, as well as about the subdivision of one of the species, the common shrew (Sorex araneus), into intraspecific chromosomal races. The list of the 75 races known so far is included (26 of them dwell in Russia).     

Candidatus "Thiodictyon syntrophicum", sp. nov., a new purple sulfur bacterium isolated from the chemocline of Lake Cadagno forming aggregates and specific associations with Desulfocapsa sp

Strain Cad16(T) is a small-celled purple sulfur bacterium (PSB) isolated from the chemocline of crenogenic meromictic Lake Cadagno, Switzerland. Long term in situ observations showed that Cad16(T) regularly grows in very compact clumps of cells in association with bacteria belonging to the genus Desulfocapsa in a cell-to-cell three dimensional structure. Previously assigned to the genus Lamprocystis, Cad16(T), was here reclassified and assigned to the genus Thiodictyon. Based on comparative 16S rRNA gene sequences analysis, isolate Cad16(T) was closely related to Thiodictyon bacillosum DSM234(T) and Thiodictyon elegans DSM232(T) with sequence similarities of 99.2% and 98.9%, respectively. Moreover, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analysis separated Cad16(T) from other PSB genera, Lamprocystis and Thiocystis. Major differences in cell morphology (oval-sphere compared to rod-shaped) and arrangement (no netlike cell aggregates), carotenoid group (presence of okenone instead of rhodopinal), chemolithotrophic growth as well as the ability to form syntrophic associations with a sulfate-reducing bacteria of the genus Desulfocapsa suggested a different species within the genus Thiodictyon. This isolate is therefore proposed and described as Candidatus "Thiodictyon syntrophicum" sp. nov., a provisionally novel species within the genus Thiodictyon.     

A review of the ethnomedicinal uses,phytochemistry and pharmacology of the <Emphasis Type="Italic">Pleiocarpa</Emphasis> genus

Pleiocarpa genus is a flowering plant from the Apocynaceae family which are rich sources of phytochemicals and have been reported to be useful in the treatment of gastrointestinal ailments, fever, malaria, pain, diabetes and cancer. The aim of this review is to present the past and current ethnomedicinal uses, phytochemistry and the pharmacology of Pleiocarpa genus which are underexploited as revealed through this review in order to enhance its potential source of phytochemical leads in medicine. Some pharmacological activities of these plants based on their acclaimed ethnomedicinal uses have been investigated by various researchers. The chemical profile of the genus is limited to alkaloids and triterpenoids, where indole alkaloids may be considered as important taxonomical markers.     

Metarhizium frigidum sp. nov.: a cryptic species of M. anisopliae and a member of the M. flavoviride complex

The anamorph genus Metarhizium is composed of arthropod pathogens, several with broad geographic and host ranges. Members of the genus, including "M. anisopliae var. frigidum" nomen nudum and Metarhizium flavoviride, have been used as biological insecticides. In a recent revision of the genus the variety "M. anisopliae var. frigidum" was suggested to be a synonym of M. flavoviride based largely on ITS sequence phylogenetic analysis. In this study we conducted morphological evaluations and multigene phylogenetic analyses with EF-1alpha, RPB1 and RPB2 for strains of M. flavoviride and "M. anisopliae var. frigidum." Included in these evaluations were the ex-type of M. flavoviride var. flavoviride and what likely would be considered the "ex-type' of the invalidly published taxon "M. anisopliae var. frigidum". Based on morphological and molecular evidence we conclude that "M. anisopliae var. frigidum" is distinct from M. flavoviride and the taxon M. frigidum sp. nov. is described.     

A curious occurrence of Hazenia broadyi spec. nova in Antarctica and the review of the genus Hazenia (Ulotrichales, Chlorophyceae)

Freshwater filamentous green algae with branched thalli are almost unknown from the Antarctic region. They have rarely been recorded from maritime Antarctica and from sub-Antarctic Islands with rich phanerogamic vegetation. In the genus Hazenia, only one unidentified species was reported from several subaerial sites on Signy Island in 1979. However, unique populations of this genus were recently found in the stony littoral zone of two stable shallow lakes in the northern deglaciated region of James Ross Island (NE Antarctic Peninsula). These populations have a specialized ecology; they participate in the microvegetation on the flattened surfaces of stones in the littoral zones of lakes. The dominant green filamentous and richly branched alga from these communities was transferred to monospecific culture and studied in detail. Molecular sequence data (18S ribosomal DNA and the internal transcribed spacer) indicate that it belongs to the genus Hazenia (Bold in Am J Bot 45:737–743, 1958). Based on distinct molecular, morphological, and ecological characters, this alga was described as a new species (Hazenia broadyi spec. nova). A review of the genus Hazenia, based on molecular phylogenetic analyses of available strains, was also performed.     

Molecular phylogeny of the volvocine flagellates.

Phylogenetic studies of approximately 2,000 bases of sequence from the large and small nuclear-encoded ribosomal RNAs are used to investigate the origins of the genus Volvox. The colonial and multicellular genera currently placed in the family Volvocaceae form a monophyletic group that is significantly closer phylogenetically to Chlamydomonas reinhardtii than it is to the other unicellular green flagellates that were tested, including Chlamydomonas eugametos, Chlorella pyrenoidosa, and Haematococcus lacustris. Statistical analysis of 251 phylogenetically informative nucleotide positions rejects the "volvocine lineage" hypothesis, which postulates a monophyletic evolutionary progression from unicellular organisms (such as Chlamydomonas), through colonial organisms (e.g., Gonium, Pandorina, Eudorina, and Pleodorina) demonstrating increasing size, cell number, and tendency toward cellular differentiation, to multicellular organisms having fully differentiated somatic and reproductive cells (in the genus Volvox). The genus Volvox appears not to be monophyletic. Volvox capensis falls outside a lineage containing other representatives of Volvox (V. aureus, V. carteri, and V. obversus), and both of these Volvox lineages are more closely related to certain colonial genera than they are to each other. This implies either a diphyletic origin of Volvox from different colonial volvocacean ancestors, a phylogenetic derivation of some of the colonial genera from a multicellular (i.e., Volvox) ancestor, or both. Considered together with previously published observations, these results suggest that the different levels of organizational and developmental complexity found in the Volvocaceae represent alternative stable states, among which evolutionary transitions have occurred several times during the phylogenetic history of this group.