柴达木盆地陆相第四系中具刺介形类新属Qaidamocypris的发现…

一个壳面布有许多细刺的玻璃介亚科新成员－Ｑａｉｄａｍｏｃｙｐｒｉｓ ｇｅｎ．ｎｏｖ．在青藏高原北部的柴达木盆地陆相更新统中产出。这一新属的发现又一次表明,与海洋里有复杂壳饰介形类一样,在一定的条件下,内陆湖泊同样也能有多刺种类生存。     

中国介蕨属孢子形态的研究

采用光学显微镜和扫描电子显微镜对国产介蕨属Dryoathyrium 14种植物及宁陕蛾眉蕨Lunathyri- um ningshenense 的孢子形态进行了观察。介蕨属孢子单裂缝,两侧对称,极面观为椭圆形,赤道面观为半 圆形或肾形。根据其周壁褶皱隆起形成的表面纹饰,介蕨属孢子可分为3种类型：第一种类型的周壁 具有网状或拟网状脊状纹饰,具此类型的种有翅轴介蕨D．pterorachis,中华介蕨D．chinense,朝鲜介蕨 D．coreanum;第二种类型的周壁具有裂片状、弯裂片状或瘤状突起,具此类型的种有介蕨D．boryanum, 陕甘介蕨D．confusum,无齿介蕨D．edentulum,鄂西介蕨D.henryi,华中介蕨D．okuboanum,川东介 蕨D．stenopteron,刺毛介蕨D．setigerum,绿叶介蕨D．viridifrons;第三类型的周壁具有刺状、不规则 棒状或乳头状突起,具此类型的种有直立介蕨D．erectum,镰小羽介蕨D．falcatipinnulum,蛾眉介蕨D． unifurcatum。宁陕蛾眉蕨的孢子形态与朝鲜介蕨D．coreanum 十分相似,支持将前者作为后者的异名的分类处理。     

陕南镇巴早寒武世似软舌螺化石一新种--Torellella bisulcata sp.nov.

对采自陕西镇巴小洋剖面下寒武统西蒿坪段的似软舌螺类(hayolithelminths)化石进行了研究,描述了一新种Torellella bisulcata sp．nov．,其主要特征为：磷质管状壳体,横切面透镜状,壳管的两个宽面凸度不等,一面为弧状,另一面扁平;壳管直或微弯曲,在壳管的两个窄的侧面各具一纵向浅凹沟,壳面光滑或饰有微弱的横向纹线。简要地讨论了似软舌螺类化石的生物亲缘关系,认为迄今为止,其仍为分类位置不明的化石类别。西蒿坪段中下部产有三叶虫颊刺和颈刺,表明此段沉积地层属于下寒武统筇竹寺阶而非梅树村阶。     

东营凹陷沙河街组介形虫化石保存特征研究及应用

本文对山东东营凹陷沙河街组介形虫化石壳体的保存特征进行了研究。研究结果表明：沙河街组介形虫化石壳体颜色可分为浅色、中色和深色三种类型;按有无充填物,可分为未充填壳和充填壳两种,其中充填壳充填物的成分有方解石、白云石、黄铁矿和泥质四种;按完整程度有双瓣壳、单瓣壳和碎壳。文中对这些保存特征形成的原因进行了讨论,最后以一口井的研究结果为例,探讨了介形虫保存特征在古湖泊学及石油地质方面的应用。     

抚顺雕饰叶肢介科一新属——阿巴嘎旗叶肢介

叶肢介化石的壳饰有三种基本类型,即针孔型、网格型和线脊型。新属阿巴嘎旗叶肢介(Abagaqiella)的壳饰属线脊型。具有线脊型壳饰的叶肢介化石大致有20多个属,分属于Asmussiidae Kobayashi,1954和Fushunograptidae Wang,1974(=Orthestheriida e Chang et Chen,1975)。Abagaqiella gen.nov.属于后一科。这一科的壳饰特征是:线脊直或弯曲,疏或密,大     

Difalsisca ——叠饰伪转叶肢介新属

叠饰伪转叶肢介(Difalsisca)的特征是初生壳大,背缘末端的后背角反弯曲,装饰为小针网状,在壳的后腹部生长带上有叠网状装饰。新属与伪转叶肢介属(Falsisca)的区别就是具有叠网状装饰,其他特征均相似。叠饰叶肢介科(Diestheriidae Zhang et Chen)是1976年建立的。主要特征是在壳表面原有的网、线和线网状装饰之上又叠覆一层更大的网状物,称为“叠网状装饰”,它主要分布在壳的后腹部生长带上。本科包括叠饰叶肢介属(Di-estheria Chen,1976),新叠饰叶肢介属(Neod-     

贵州剑河八郎寒武系“清虚洞组”Tuzoia*

大型双瓣壳节肢动物吐卓虫Tuzoia是一个形态丰富的属,广泛分布在北美、中国、澳大利亚和捷克的寒武系第二、三统中。文中报道了采自贵州剑河八郎"清虚洞组"的吐卓虫的2种:即Tuzoia jianheensis sp.nov.与T.bispinosa Yuan and Zhao,1999。新种的主要特征为中后刺、后腹刺细长,腹部边缘发育有锯齿状边缘刺,壳面网纹细密,不同于Tuzoia的其他种,有较强地域性。新种化石数量占优,占总数三分之二。T.bispinisa背缘发育有三角形或近三角形背刺,前后铰突发育,壳面的网纹以不规则六边形为主,网眼大。T.jianheensis sp.nov.与上覆凯里组的T.bispinosa对比研究,得出Tuzoia的壳长有变短的趋势。     

新疆的刺球座属、穴壳属及普氏腔孢属

本文报道了新疆腔菌纲座囊菌目刺球座属（Ｌａｓｉｏｂｏｔｒｙｓ）、穴壳属（Ｄｏｔｈｉｏｒａ）和普氏腔孢属（Ｐｌｏｗｒｉｇｈｔｉａ）的六种子囊菌,即：忍冬刺球座菌（Ｌ．ｌｏｎｉｃｅｒａｅ）、花揪穴壳菌（Ｄ．ｓｏｒｂｉ）及其无性阶段花揪疡壳孢（Ｄｏｔｈｉｃｈｉｚａ ｓｏｒｂｉ）、茶Ｂｉａｏ子普氏腔孢菌（Ｐ．ｒｉｂｅｓｉａ）、小檗普氏腔孢菌（Ｐ．ｂｅｒｂｅｒｉｄｉｓ）、沙棘普氏腔孢菌（Ｐ．ｈｉｐｐｏｐｈａ     

几种具纤毛分生孢子的腔孢菌

本文报道了河北省具纤毛分生孢子的腔孢菌５种,它们隶属于多毛孢属,星毛孢属,刺杯毛孢属和双毛壳孢属。其中多毛孢属和星毛孢属系国内新记录属。记载了一新种中国多毛孢和一中国新记录种甘蔗星毛孢。在刺杯毛孢属和双毛壳孢属内共鉴定出３个种,它们是槭刺杯毛孢,刚毛刺杯毛孢和双毛壳孢。文中对这些种进行了详细描述,新种有拉丁文描述。研究标本保藏于河北省科学院生物研究所。     

湘中地区下石炭统似无饰介科(Paraparchitidae)的几个新属种

我队自1978年以来在湖南中部地区地表和井下早石炭世地层,陆续采到丰富的介形类化石,其中以似无饰介科(Paraparchitidae)具后背刺的属种较多。笔者研究了这些具后背刺的介形类,计3属,包括1新属、7新种。这批材料的发现对我国早石炭世介形类的研究和地层对比都具有一定的意义。在似无饰介科中,具后背刺的属种较常见,自晚泥盆世开始出现,早石炭世大量繁盛,至二叠纪衰亡,它们具有一定的地层意义。B.Kellet     

A new surface gliding species of Chironomidae: An independent invasion of marine environments and its evolutionary implications

Insects have invaded marine habitats only rarely and secondarily. Recently, we discovered a flightless dipteran species skating rapidly on the surface of seawater ponds at the Pacific coast of eastern China. Morphological analyses initially suggested an isolated position of the non‐biting midge, suggesting the erection of a new genus within Chironomini (Diptera: Chironomidae). However, an analysis of molecular data revealed that the marine species is in fact nested within the species‐rich genus Dicrotendipes. The apparent conflict between molecular and morphological data can be easily explained. It is likely that the new species has evolved a series of autapomorphic adaptations. These traits clearly distinguish the taxon from other species of the genus but do not justify the erection of a new supraspecific taxon, which would render Dicrotendipes paraphyletic. The switch to marine environments was likely a trigger for various morphological modifications resulting from increased selective pressure. Molecular data suggest that the potential speciation event occurred around 19–29 Ma, linked with a migration from freshwater to seawater ponds along the Pacific Ocean. Considering the results of our analysis, we place the flightless marine skater in the genus Dicrotendipes. All life stages of Dicrotendipes sinicus Qi & Lin sp. n. are described and illustrated, associated with larvae obtained by rearing or confirmed through association with DNA barcodes. The biology and ecology of the species are outlined based on collection data and in situ observations. Evolutionary patterns linked with repeated invasions of marine habitats are discussed.     

A new species ofEupenicillium from marine sediment

A new species ofEupenicillium isolated from marine sediment,Eupenicillium limosum, is described and illustrated. This species is characterized by subglobose ascospores with spinulose surface ornamentation and irregular biverticillate penicilli.     

Use of 16S ribosomal DNA for delineation of marine bacterioplankton species

All of the marine bacterioplankton-derived 16S ribosomal DNA sequences previously deposited in GenBank were reanalyzed to determine the number of bacterial species in the oceanic surface waters. These sequences have been entered into the database since 1990. The rate of new additions reached a peak in 1999 and subsequently leveled off, suggesting that much of the marine microbial species richness has been sampled. When the GenBank sequences were dereplicated by using 97% similarity as a cutoff, 1,117 unique ribotypes were found. Of the unique sequences, 609 came from uncultured environmental clones and 508 came from cultured bacteria. We conclude that the apparent bacterioplankton species richness is relatively low.     

Use of 16S Ribosomal DNA for Delineation of Marine Bacterioplankton Species

All of the marine bacterioplankton-derived 16S ribosomal DNA sequences previously deposited in GenBank were reanalyzed to determine the number of bacterial species in the oceanic surface waters. These sequences have been entered into the database since 1990. The rate of new additions reached a peak in 1999 and subsequently leveled off, suggesting that much of the marine microbial species richness has been sampled. When the GenBank sequences were dereplicated by using 97% similarity as a cutoff, 1,117 unique ribotypes were found. Of the unique sequences, 609 came from uncultured environmental clones and 508 came from cultured bacteria. We conclude that the apparent bacterioplankton species richness is relatively low.     

Fine structure of Pyramimonas octopus sp. nov., an octoflagellated benthic species of Pyramimonas (Prasinophyceae), with some observations on its ecology

A new octoflagellated species of Pyramimonas is described from three localities in Denmark. It is characterized by its ecology, being a marine psammophilic species associated with sand grains, and by details of the scaly covering on the cell surface. In the scale cover there are similarities to P. amylifera and to P. tetrarhynchus. P. octopus is distinguished by the possession of circular body scales of a type not previously found in the genus.
The general fine structure of the new species is described with emphasis on scale structure, the internal structure of the cell body and the flagella.     

Evolutionary Dynamics in the Southwest Indian Ocean Marine Biodiversity Hotspot: A Perspective from the Rocky Shore Gastropod Genus Nerita

The Southwest Indian Ocean (SWIO) is a striking marine biodiversity hotspot. Coral reefs in this region host a high proportion of endemics compared to total species richness and they are particularly threatened by human activities. The island archipelagos with their diverse marine habitats constitute a natural laboratory for studying diversification processes. Rocky shores in the SWIO region have remained understudied. This habitat presents a high diversity of molluscs, in particular gastropods. To explore the role of climatic and geological factors in lineage diversification within the genus Nerita, we constructed a new phylogeny with an associated chronogram from two mitochondrial genes [cytochrome oxidase sub-unit 1 and 16S rRNA], combining previously published and new data from eight species sampled throughout the region. All species from the SWIO originated less than 20 Ma ago, their closest extant relatives living in the Indo-Australian Archipelago (IAA). Furthermore, the SWIO clades within species with Indo-Pacific distribution ranges are quite recent, less than 5 Ma. These results suggest that the regional diversification of Nerita is closely linked to tectonic events in the SWIO region. The Reunion mantle plume head reached Earth’s surface 67 Ma and has been stable and active since then, generating island archipelagos, some of which are partly below sea level today. Since the Miocene, sea-level fluctuations have intermittently created new rocky shore habitats. These represent ephemeral stepping-stones, which have likely facilitated repeated colonization by intertidal gastropods, like Nerita populations from the IAA, leading to allopatric speciation. This highlights the importance of taking into account past climatic and geological factors when studying diversification of highly dispersive tropical marine species. It also underlines the unique history of the marine biodiversity of the SWIO region.     

A survey on bacteria inhabiting the sea surface microlayer of coastal ecosystems

Bacterial populations inhabiting the sea surface microlayer from two contrasted Mediterranean coastal stations (polluted vs. oligotrophic) were examined by culturing and genetic fingerprinting methods and were compared with those of underlying waters (50 cm depth), for a period of two years. More than 30 samples were examined and 487 strains were isolated and screened. Proteobacteria were consistently more abundant in the collection from the pristine environment whereas Gram-positive bacteria (i.e., Actinobacteria and Firmicutes) were more abundant in the polluted site. Cythophaga-Flavobacter-Bacteroides (CFB) ranged from 8% to 16% of total strains. Overall, 22.5% of the strains showed a 16S rRNA gene sequence similarity only at the genus level with previously reported bacterial species and around 10.5% of the strains showed similarities in 16S rRNA sequence below 93% with reported species. The CFB group contained the highest proportion of unknown species, but these also included Alpha- and Gammaproteobacteria. Such low similarity values showed that we were able to culture new marine genera and possibly new families, indicating that the sea-surface layer is a poorly understood microbial environment and may represent a natural source of new microorganisms. Genetic fingerprinting showed, however, no consistent differences between the predominant bacterial assemblages from surface microlayer and underlying waters, suggesting that the presence of a stable and abundant neustonic bacterial community is not a common trait of coastal marine environments.     

Keeping pace with climate change: what can we learn from the spread of Lessepsian migrants?

Species need to move to keep pace with changing climates, but we do not know if species can move at the required speed. Spread rates of native species may underestimate how fast species can move, we therefore assessed how fast Lessepsian species (marine non‐native species that invaded the Mediterranean from the Red Sea through the Suez Canal) can spread to give a ‘best‐case’ assessment of the effects of climate change on marine biodiversity. We show that about 20% of Lessepsian species could not spread fast enough to keep pace with climate change in about 20% of the global seas and this suggests that climate change may lead to biodiversity loss. The velocity of climate change on the seabed is much lower than at the sea surface, and as a result of this the proportion of species that keep pace with climate change at the seabed was much larger than at the sea surface. This suggests that locations at depth could act as refuges for slow dispersing species. Our analysis compared different estimates of the spreading abilities of marine species and showed that the estimate of spread rates strongly affects the predicted effect of climate change on biodiversity. Providing more accurate estimates of the spreading ability of marine species should therefore have priority if we want to predict the effect of climate change on marine biodiversity. This study is a first approximation of the potential scale and distribution of global marine biodiversity loss and can provide benchmark estimates of the spread rates that species could achieve in colonizing suitable habitat. Assisted colonization may be required to maintain biodiversity in the most strongly affected areas.     

北部湾海洋植物及其共附生微生物次级代谢产物研究进展(综述)

海洋植物及其共附生微生物是海洋生物的重要组成部分,能够产生许多结构新颖、活性独特的次级代谢产物,承担多种生理生态功能。北部湾海洋植物物种资源丰富,据统计,海洋植物有3门43种。该文综述了从2002年起北部湾海洋植物及其共附生微生物次级代谢产物的研究进展,从11种红树植物和7种共附生微生物中获得59个新化合物和35个已知活性化合物,从3种海草植物中获得3个新化合物和7个已知活性化合物,从6种海藻植物和1种共附生微生物中获得25个新化合物和8个已知活性化合物,主要涉及结构类型有萜类、生物碱、黄酮类、甾醇,多数具有良好的抗菌、抗氧化、抗肿瘤、抗炎、增强机体免疫力等功效。在此基础上,进一步提出了北部湾海洋植物研究方向及后续的研究建议。该综述为深入研究和开发利用北部湾海洋植物及其共附生微生物提供了参考。     

Dispersal in Marine Organisms without a Pelagic Larval Phase

In contrast to marine organisms whose offspring go through an extended planktonic stage, the young of others develop directly into benthic juveniles or into yolky nonfeeding larvae that spend only a few hours in the plankton before settling. Yet, paradoxically, many such species have geographic distributions that are comparable to those with a pelagic dispersal stage. This article reviews some of the ways in which these organisms can expand their distributions: drifting, rafting, hitchhiking, creeping, and hopping. Drifting applies to species in which larvae may be short-lived, but adults can detach or be detached from their benthic substratum and be passively carried to new areas, floating at the water's surface or below it. Many encrusting species and mobile species can spread by rafting, settling on natural or artificial floating substrata which are propelled by wind and currents to new regions. Hitchhiking applies to those attaching to vessels or being carried in ballast water of ships to a distant region in which their offspring can survive. Other marine species extend their distributions by hopping from one island of hard substratum or favorable sedimentary microhabitat to another, while creeping species extend their distributions along shores or shelves where habitats remain similar for long distances.