真黏菌生活史研究概述

真黏菌是世界性普遍分布的一类原生动物,其生活史具有单核黏变形体和游动胞、多核原质团和具孢子的子实体等阶段。掌握真黏菌生活史的全貌是该类群生物学研究的重要方面,同时也为分类学和系统发育学研究提供理论支持。本文回顾了真黏菌生活史的研究发展,对已报道生活史的物种进行统计分析,以加深对真黏菌生活史的科学认知,为深入研究真黏菌生活史特征等生物学问题提供理论参考。     

第八届黏菌分类学及生态学国际会议

1993年9月,第一届黏菌分类学及生态学国际会议（ICSEM）在英国西北部的美丽海滨旅游城市切斯特（Chester）拉开了帷幕,黏菌学者从此拥有了一个属于自己的论坛和交流的同地,世界黏菌学研究也进人了飞速发展的时期。根据会议上各国学者的共同愿望,达成了每隔3年召开1次类似会议的共识,一直延续至今,现已成功召开了七届黏菌大会。     

中国绒泡菌属黏菌的物种及分布

绒泡菌属是黏菌纲最大的一个属,通过标本的鉴定和复核以及文献考证等分类学研究,重新整理和报道了中国绒泡菌属黏菌的物种资料,计有93种,探讨了它们的分布特征和地理成分,一些种在中国的分布省区被增补。     

中国双皮菌属黏菌的物种及分布

双皮菌属是黏菌纲中最重要的属之一,通过标本的鉴定和复核以及文献考证等分类学研究,重新整理和报道了中国双皮菌属黏菌的物种资料,计有24种,探讨了它们的分布特征和与基质的联系,增补了一些种在中国的分布省区,对过去报道的某些种的学名和分类地位进行了更正.     

黏菌学的发展

黏菌是一类在陆地生态系统中广泛分布的真核生物,在其生活史的不同阶段,既有体现原生动物运动性的营养体,也具有高度特异化的繁殖体,其形态结构与生理特征,兼具了“菌物”与“动物”的特性,独特的进化地位以及与环境、人类健康的密切关系,使得以黏菌为模式生物的研究在生物学、遗传学、生理学、生态学、信息科学等学科均具有广泛的科学意义和重要的应用价值。自17世纪以来,黏菌研究者们从早期的经典分类学,逐步拓展到从生物学各分支学科领域系统全面地认识黏菌类群。在近几十年中,黏菌研究在系统学、生物学、生态学等方向取得了长足的进步。本文扼要介绍了黏菌学在各领域内的代表性研究进展和前沿性科学问题,同时对相关领域未来的发展进行了展望。     

历届黏菌分类学及生态学国际会议介绍

正第一届英国切斯特1993年9月6日至11日,在英国西北部的美丽海滨旅游城市切斯特召开了第一届黏菌分类学及生态学国际会议(ICSEM-1);这个日子在人类历史长河中像它之前或之后的任何一天一样,人们黎明即起,日落而息,但对全世界的黏菌学者来说却是一个永远载入史册的纪念日!黏菌学者开始拥有了一个属于自己的论坛和交流的园地。出席这次会议的有:英     

第八届黏菌分类学及生态学国际会议第二轮通知

<正>1993年,第一届黏菌分类学及生态学国际会议(简称ICSEM)在英国西北部的城市切斯特召开。会议每三年召开一次,至今已经成功举办了7届。第八届黏菌分类学及生态学国际会议将于2014年8月12日在中国长春召开。这是该会议第一次在亚洲举办,由吉林农业大学和吉林省科学技术协会承办。会议采取研讨与考察结合的方式,主要有学术讨论、workshop、墙报展示、摄影展及野外考察等内容。会议在为国内外黏菌爱好者搭建学术交流与沟通平台的同时,也为中国菌物学者提供一次相互交流、相互学习的机会。大会组委会真诚邀请您能够抽出宝贵时间参会,共同推动中国菌物事业的发展。     

中国热带黏菌的已知种类

我国广东、广西、云南和台湾4省区的南部及海南、香港和澳门全境均在北回归线以南,属于地理上的热带。为了全面系统地开展我国热带地区黏菌资源的多样性和分类学研究,文中通过标本采集、鉴定和复核以及文献考证研究了已知的发生于中国热带地区的黏菌种类,对一些物种分类地位和名称变化进行了更新,同时记述了每个物种的生境和在我国热带地区的分布。结果表明:中国热带地区现知黏菌6目13科35属160种,其中,广东南部为23种,广西南部为61种,海南为33种,云南南部为67种,台湾南部为26种,香港为66种,澳门为10种。从黏菌的目级水平来看,中国热带地区现知黏菌鹅绒菌目1种,刺轴菌目5种,无丝菌目22种,团毛菌目32种,绒泡菌目73种,发网菌目27种。     

中国黏菌资源研究进展

黏菌是陆地生态系统中生物的重要组成,全球已报道1 100余种,我国黏菌资源丰富,已知物种约占全球黏菌种类的36.4%。回顾了中国黏菌资源研究的发展,对黏菌新种的发现、黏菌物种多样性编目,以及我国温带、亚热带、热带及高原温带等代表地区的黏菌资源研究进行了区域性总结,并对今后的研究方向提出了建议。     

黏菌物种多样性及其与影响因子关系的研究进展

黏菌是一类具有独特特征且广泛分布在陆地生态系统中的菌物,具有调节微生境微生物群落、影响营养和生物量分配等作用。黏菌的物种多样性及影响因素一直是黏菌生态学的研究热点。本文综述了不同微生境中黏菌的发生情况以及影响黏菌物种多样性的非生物因子和生物因子3个方面的研究进展,进一步揭示黏菌在生态系统中的生态功能。     

节腹泥蜂族分类研究进展

本文对节腹泥蜂族的分类研究现状进行了总结。该族目前世界已知2属911种。文中对该族的分类研究简史和生物学特性作了简要概述,并对种类的地理分布作了统计分析。     

Vertebral evolution and the diversification of squamate reptiles

Taxonomic, morphological, and functional diversity are often discordant and independent components of diversity. A fundamental and largely unanswered question in evolutionary biology is why some clades diversify primarily in some of these components and not others. Dramatic variation in trunk vertebral numbers (14 to >300) among squamate reptiles coincides with different body shapes, and snake-like body shapes have evolved numerous times. However, whether increased evolutionary rates or numbers of vertebrae underlie body shape and taxonomic diversification is unknown. Using a supertree of squamates including 1375 species, and corresponding vertebral and body shape data, we show that increased rates of evolution in vertebral numbers have coincided with increased rates and disparity in body shape evolution, but not changes in rates of taxonomic diversification. We also show that the evolution of many vertebrae has not spurred or inhibited body shape or taxonomic diversification, suggesting that increased vertebral number is not a key innovation. Our findings demonstrate that lineage attributes such as the relaxation of constraints on vertebral number can facilitate the evolution of novel body shapes, but that different factors are responsible for body shape and taxonomic diversification.     

Taxonomic distinctness and diversity of a hyperseasonal savanna in central Brazil

Savannas are characterized by a sharp seasonality, in which the water shortage defines the community functioning. Hyperseasonal savannas, however, experience additionally waterlogging in the rainy season. Since waterlogging may cause local extinctions of intolerant species, we asked whether waterlogging constricts the phylogenetic structure of a hyperseasonal savanna. We studied a hyperseasonal cerrado, comparing it with a nearby seasonal cerrado, never waterlogged, in Emas National Park, central Brazil. In each vegetation form, we sampled all vascular plants by placing fifty 1-m² quadrats in five surveys. We compared the phylogenetic structure of both vegetation forms, calculating their taxonomic distinctness, taxonomic diversity, expected taxonomic distinctness, and species, genus, and family similarities. The taxonomic distinctness of both cerrados was similar and the values of similarities were high, but taxonomic diversity and expected taxonomic distinctness were lower in the hyperseasonal cerrado than in the seasonal one. Assuming that phenotypic attraction is the major process organizing local communities, the waterlogging in hyperseasonal cerrado assembles phylogenetically unrelated species that have converged on similar habitat use. As a consequence, the habitat use of hyperseasonal cerrado species is a trait widespread in the phylogeny of seasonal cerrado. Waterlogging constrains the phylogenetic structure of the hyperseasonal cerrado, especially by reducing species diversity. In more ecological terms, we can only fully assess the phylogenetic structure of a community if we consider the species abundance.     

A parametric diversity measure combining the relative abundances and taxonomic distinctiveness of species

Most ecological diversity indices summarize the information about the relative abundances of species without reflecting taxonomic differences between species. Nevertheless, in environmental conservation practice, data on species abundances are mostly irrelevant and generally unknown. In such cases, to summarize the conservation value of a given site, so‐called ‘taxonomic diversity’ measures can be used. Such measures are based on taxonomic relations among species and ignore species relative abundances. In this paper, bridging the gap between traditional biodiversity measures and taxonomic diversity measures, I introduce a parametric diversity index that combines species relative abundances with their taxonomic distinctiveness. Due to the parametric nature of the proposed index, the contribution of rare and abundant species to each diversity measure is explicit.     

铁线莲属翅果铁线莲组修订

对毛茛科铁线莲属Clematis中单型的翅果铁线莲组sect .Pterocarpa进行了分类学修订,写出了此组及其惟一种,翅果铁线莲C.brachyura的分类学简史和形态描述,给出此种的插图。根据其体态及花构造近似亚洲东部的辣蓼铁线莲C.mandshuricaRupr .和圆锥铁线莲C.ternifloraDC.(二种均为威灵仙组sect .Clematis的成员) ,推测翅果铁线莲可能源自威灵仙组。     

Phylogenetic significance of egg shell variation in tardigrades

Freshwater and semiterrestrial tardigrades produce either smooth shelled eggs laid in the exuvium or ornamented eggs laid freely, in contrast to the more primitive marine heterotardigrades which have smooth shelled free-laid eggs. Data are presented on the observation of free-laid ornamented eggs in the primitive non marine heterolardigrade genus Oreella and in a number ot e.utardigrade genera including Eohypsibius, Amphilus, Minibiotus and Macrobiotus. These findings have provided a sound basis for the formulation of a hypothesis in which the evolution of the tardigrade egg can be explained by two separate events. The first is the acquisition of ornamentation and the second is the utilization of the exuvium for oviposition with subsequent loss of egg ornamentation. This hypothesis is consistent with new taxonomic arrangements within eutardigrade families and genera (based on character) of the animals) which have led to a more uniform assortment in terms of egg types. This means that egg type (smooth or ornamented) becomes a valid taxonomic character at the generic level.     

Decoupling of taxonomic diversity and morphological disparity during decline of the Cambrian trilobite family Pterocephaliidae

Although discordance between taxonomic diversity and morphological disparity is common, little is known about the underlying dynamics that drive this decoupling. Early in the history of the Cambrian trilobite family Pterocephaliidae, there was an increase in taxonomic diversity and morphological diversity. As taxonomic diversity declined in the later history of the clade, range of variation stayed high and disparity continued to increase. However, per‐branch rates of morphological evolution estimated from a recent phylogeny decreased with time. Neither within‐trait nor within‐species variation increased or decreased, suggesting that the declining rates of morphological evolution were more likely related to ecological opportunity or niche partitioning, rather than increasing intrinsic constraints. This is further supported by evidence for increased biofacies associations throughout the time period. Thus, the high disparity seen at low taxonomic diversity late in the history of this clade was due to extinction – either random or targeting mean forms – rather than increased rates of morphological evolution. This pattern also provides a scenario that could account for instances of low taxonomic diversity but high morphological disparity in modern groups.     

Taxonomic identification bias does not drive patterns of abundance and diversity in theropod dinosaurs

The ability of palaeontologists to correctly diagnose and classify new fossil species from incomplete morphological data is fundamental to our understanding of evolution. Different parts of the vertebrate skeleton have different likelihoods of fossil preservation and varying amounts of taxonomic information, which could bias our interpretations of fossil material. Substantial previous research has focused on the diversity and macroevolution of non-avian theropod dinosaurs. Theropods provide a rich dataset for analysis of the interactions between taxonomic diagnosability and fossil preservation. We use specimen data and formal taxonomic diagnoses to create a new metric, the Likelihood of Diagnosis, which quantifies the diagnostic likelihood of fossil species in relation to bone preservation potential. We use this to assess whether a taxonomic identification bias impacts the non-avian theropod fossil record. We find that the patterns of differential species abundance and clade diversity are not a consequence of their relative diagnosability. Although there are other factors that bias the theropod fossil record that are not investigated here, our results suggest that patterns of relative abundance and diversity for theropods might be more representative of Mesozoic ecology than often considered.     

A proposed phylogeny of the flagellated protostelids.

The flagellated members of the group of mycetozoans known as protostelids have been recognized for some time to be members of a monophyletic group which also includes the myxomycetes. This inference was based primarily upon comparisons of the flagellar apparatus of the amoeboflagellate state. However, more detailed comparisons based on the whole life history and comparisons with an outgroup were necessary to have information sufficient to determine the interrelationships within the group. Recent studies of the other states of the life history of protostelids have provided a wealth of additional morphological and developmental characters such that an in depth phylogenetic analysis is possible. The results show that the group can be resolved into two major clades, one of which contains the myxomycetes and the myxomycete-like protostelid genera, Protosporangium, Clastostelium, and Ceratiomyxa, and another which contains the protostelid genera Planoprotostelium, Cavostelium, and Ceratiomyxella. As the myxomycetes appear to be part of the ingroup, and not a sister group to the protostelids, L.S. Olive's subclass Protostelia must be considered paraphyletic.