我国有尾动物分类中几个问题的研究

本文对有尾两栖类小鲵科Hynobiidae山溪鲵属、巴鲵属、小鲵属分类研究中的同物异名,以及属称的订正方面进行了进一步探讨,认为我国山溪鲵属应为5种,无唇褶山溪鲵B.cochranae应为北方山溪鲵Batrachuperus ti-betanus同物异名。巴鲵属是一个有效属称,义乌小鲵Hynobius yiwuensis应为中国小鲵H.chinensis的同物异名,黄斑拟小鲵Pseudohynobius flavonaculatus可以暂定为秦巴北鲵Ranodon tsinoaensis的同物异名。黑抓异鲵Xenobius melanonychus是否有效种有待确定。     

中国两栖类一新种(有尾目,小鲵科)

对2003年2月、2005年11月采自广西猫儿山国家级自然保护区的1种小鲵进行了研究,认为其特征与现有的小鲵都不相同,确定为中国两栖纲有尾目小鲵科小鲵属1新种,即猫儿山小鲵Hynobius maoershanensis sp.nov..模式标本保存于广西大学动物科技学院标本室,部分副模标本(MESH05111001,MESH05111002)保存于广西猫儿山国家级自然保护区标本室.     

龙洞山溪鲵精子的超微结构

应用透射电镜和扫描电镜对龙洞山溪鲵(Batrachuperuslongdongensis)精子的超微结构进行观察和研究,探讨山溪鲵属以及小鲵科物种精子的结构特征,并探讨有尾两栖类精子结构特征的演化及其与生殖进化的关系。结果表明:1)龙洞山溪鲵的精子具小鲵科物种精子的共同特征,即精子无顶体钩,顶体呈三叶草状,尾部无线粒体,轴纤维粗大呈圆柱状等特征;2)龙洞山溪鲵精子核脊的形态结构与小鲵科其它属物种以及有尾类其它科物种精子的核脊存在明显的差别,由此可见核脊形态结构具有属或种的特异性。此外,与已有报道的有尾两栖类物种精子的结构特征进行分析比较表明:1)有尾类精子特征的分化与其受精方式的变化是一致的;2)精子结构特征支持隐鳃鲵超科为单系的推测     

巴鲵属犁骨齿列形态的研究及其与北鲵属属征的订正

巴鲵幼体的犁骨齿为位于内鼻孔间略呈“八”形的两列,其前端超出内鼻孔甚多。变态过程中．随着犁骨的生长．其上的犁骨齿前部向内侧弯成直角或锐角．因此,巴鲵属具有小鲵科中与众皆不相同的犁骨齿列型式．研究比较了巴鲵属模式种施氏巴鲵与北鲵属模式种中亚北鲵的国内外各数十号标本．包括二者的模式标本．将该二属的属征加以订正．费梁等认为巴鲵属为北鲵属的异名．可能与他们观察北鲵的标本较少(3号)以及误以为北鲵非繁殖期成体“以水栖为主,均有唇褶”所致．     

青海省发现两栖纲小鲵科无斑山溪鲵

2012年8月,在青海省果洛藏族自治州班玛县采集到小鲵科山溪鲵属标本2尾,经形态鉴定并和山溪鲵属近缘种进行线粒体Cyt b及COⅠ基因序列比较分析,鉴定为无斑山溪鲵(Batrachuperus karlschmidti),为该物种在青海省内首次发现。     

中国小鲵属一新种(两栖纲:有尾目:小鲵科)

对采自我国河南省商城的一种小鲵标本进行了研究,认为与我国产小鲵科巳知属、种及日本产小鲵属相近种均不相同,被确定为新种,即豫南小鲵Hynobius yunanicus sp.nov.。     

山溪鲵的脊柱特征,兼议有尾目脊柱的划分

为探讨有尾目脊椎的划分,本文以小鲵科的山溪鲵(Batrachuperus pinchonii)为例,运用透明骨骼双色法对其脊柱的形态特征进行了观察,并对各部分椎骨特征进行详细描述和绘图.结果显示,山溪鲵的脊椎根据椎骨是否具前关节突、横突、肋骨、肋软骨和脉弓等形态特征可分5部分;同时结合小鲵科其他20种94号标本和蝾螈科6种27号标本的脊柱特征及文献资料,讨论了有尾目脊椎的划分,认为将有尾目脊柱划分为5部分(颈椎、躯椎、荐椎、尾荐椎和尾椎)的观点较将其划分为4部分(颈椎、躯椎、荐椎和尾椎)的观点更合理.     

贵州省巴鲵属一新纪录——巫山巴鲵

正2012年3月,作者在黔西北乌蒙山区大方县三元乡考察时,发现并采集小鲵雄性成体4只,经形态特征鉴定,以及与重庆巫山(GenB ank下载)标本进行的线粒体COⅠ基因序列比对,确定为巫山巴鲵Liua shihi (Liu,1950)。迄今未见贵州省有巫山巴鲵的报道,为贵州省有尾类新纪录。本文对其形态进行描述,并测量了相关形态学数据,为巴鲵属Liua的分类学和地理分布研究提供新的数据。标本保存于贵州工程应用技术学院生态工程学院标本室。     

巴鲵属犁骨齿列形态的研究及其与北鲵属属征的订正

巴鲵幼体的犁骨齿为位于内鼻孔间略呈“八”形的两列,其前端超出内鼻孔甚多;变态过程中,随着犁骨的生长,其上的犁骨齿前部向内侧弯成直角或锐角。因此,巴鲵属具有小鲵科中与众皆不相同的犁骨齿列型式。研究比较了巴鲵属模式种施氏巴鲵与北鲵属模式种中亚北鲵的国内外各数十号标本,包括二者的模式标本,将该二属的属征加以订正。费梁等认为巴鲵属为北鲵属的异名,可能与他们观察北鲵的标本较少（３号）以及误以为北鲵非繁殖期成体“以水栖为主,均有唇褶”所致。     

湘中西部小鲵属一新种--挂榜山小鲵(两栖纲:小鲵科)

在比较和研究小鲵属Hynobius物种后 ,确定湖南省祁阳县产小鲵为一新种 ,即挂榜山小鲵Hynobiusguabangshanensissp .nov .。新种与安吉小鲵H amjiensis近似 ,它们体型较大 ;有 13条肋沟 ;前后肢贴体相向时指趾重叠较多 ;掌、突明显 ,但又有明显区别 :1)新种比安吉小鲵稍小 ,全长 139 32mm± 9 5 0mm (n=9) ;2 )犁骨齿细且排列密 ,外枝 9- 11枚、内枝 2 5 - 2 7枚 ;3)尾较短 ,平均为头体长之 70 4 % (n =9) ;4 )卵袋较短 ,香蕉形弯曲等。本文列表比较近似种 ,统计并记述了新种     

Episodes of adaptive evolution of mitochondrial genome in asiatic salamanders (Amphibia,Caudata, Hynobiidae)

To elucidate the effect of natural selection on the evolution of mitochondrial DNA (mtDNA) in Asiatic salamanders of the family Hynobiidae, nucleotide sequences of 12 protein-coding genes were analyzed. Using a mixed effects model of evolution, it was found that, in spite of the pronounced effect of negative selection on the mtDNA evolution in Hynobiidae (which is typical for the animals in general), two phylogenetic clusters, the West Asian one, represented by the genera Ranodon and Paradactylodon, and North Eurasian one, represented by the genus Salamandrella, were formed under the influence of episodic positive selection. Analysis of protein sequences encoded by the mitochondrial genome also supported the influence of positive selection on the evolution of Hynobiidae at some stages of their cladogenesis. It is suggested that the signatures of adaptive evolution detected in the mtDNA of Hynobiidae were determined by the complex and long-lasting history of their formation, accompanied by adaptation to the changing environment.     

Detection of environmental impacts by bottom trawling onPosidonia oceanica (L.) Delile meadows: sensitivity of fish and macroinvertebrate communities

Along the Mediterranean coast,Posidonia oceanica (L.) Delile meadows have a great ecological and economical importance. However, there is a general regression of these meadows due to human activities such as illegal bottom trawling, may be affecting to overall ecosystem health. We examined changes in the community structure of mobile fauna associated withP. oceanica meadows at different spatial scales and taxonomic levels. The aim of this paper was to identify the most efficient taxonomic level to use in environmental impact studies of bottom trawling. At the macroscale level (10 to 100 m), there were significant differences between sites in the densities of some fish species and also the total fish assemblage structure, at both family and species taxonomical levels. At the microscale (0.1 to 1 m), some species of amphipods and isopods showed significant differences in their population densities. In the overall analysis of community structure, the coarse taxonomical levels, such as phyla and class, did not show significant differences, however amphipods and isopods showed significant differences at family and species levels. From these results, both study scales are required to detect changes onPosidonia meadows' fauna. Monitoring of some fish species such asDiplodus annularis (Linnaeus, 1758) and the overall fish assemblage as well as the structure of the amphipod and isopod communities appears to be the most efficient tool in the assessment of environmental impacts by bottom trawling onP. oceanica meadows.     

中国巨蚓科蚯蚓的起源与演化

截至2017年中国已记录巨蚓科蚯蚓579种(亚种), 优势类群为远盲蚓属(Amynthas)与腔蚓属(Metaphire), 其丰富的物种多样性值得深入研究。近年来的研究指出联合形态分类与分子系统发育可较好地探讨中国巨蚓科蚯蚓的起源、分化与扩散。本文概述了中国巨蚓科蚯蚓物种的起源、分化时间以及扩散历程, 探讨了受精囊孔、盲肠形状等重要特征的演化, 分析了现行分类系统的缺陷。多项研究表明, 中国巨蚓科主要类群的祖先起源于中南半岛, 于白垩纪末期至新生代初期进入中国, 在新生代得以繁荣发展; 受精囊孔的对数或位置是多起源的, 盲肠形状演化中有祖征重现的现象, 故使用少数形态特征进行类群划分的现行分类系统有待改进。此外, 中国巨蚓科蚯蚓的具体演化机制及影响因素仍不明确。因此, 在未来研究中整合形态特征、分子数据与地理格局、地质历史及环境因子等信息, 定量分析类群演化与古地理、生物与非生物因素间的关系, 将有助于全面厘清中国巨蚓科蚯蚓演化的具体机制。     

Patterns in freshwater diatom taxonomic distinctness along an eutrophication gradient

1. A variety of species richness measures have been used to assess the effects of environmental degradation on biodiversity. Such measures can be highly influenced by sample size, sampling effort, habitat type or complexity, however, and typically do not show monotonic responses to human impact. In addition to being independent of the degree of sampling effort involved in data acquisition, effective measures of biodiversity should reflect the degree of taxonomical relatedness among species within ecological assemblages and provide a basis for understanding observed diversity for a particular habitat type. Taxonomic diversity or distinctness indices emphasize the average taxonomic relatedness (i.e. degree of taxonomical closeness) between species in a community. 2. Eutrophication of freshwater ecosystems, mainly due to the increased availability of nutrients, notably phosphorus, has become a major environmental problem. Two measures of taxonomic distinctness (Average Taxonomic Distinctness and Variation in Taxonomic Distinctness) were applied to surface sediment diatoms from 45 lakes across the island of Ireland to examine whether taxonomic distinctness and nutrient enrichment were significantly related at a regional scale. The lakes span a range of concentrations of epilimnic total phosphorus (TP) and were grouped into six different types, based on depth and alkalinity levels, and three different categories according to trophic state (ultra‐oligotrophic and oligotrophic; mesotrophic; and eutrophic and hyper‐eutrophic). 3. The taxonomic distinctness measures revealed significant differences among lakes in the three different classes of trophic state, with nutrient‐rich lakes generally more taxonomically diverse than nutrient‐poor lakes. This implies that enrichment of oligotrophic lakes does not necessarily lead to a reduction in taxonomic diversity, at least as expressed by the indices used here. Furthermore, taxonomic distinctness was highly variable across the six different lake types regardless of nutrient level. 4. Results indicate that habitat availability and physical structure within the study lakes also exert a strong influence on the pattern of taxonomic diversity. Overall the results highlight problems with the use of taxonomic diversity measures for detecting impacts of freshwater eutrophication based on diatom assemblages.     

DNA base composition, susceptibility to bacteriophages and interspecific transformation as criteria for classification in the genus Bacillus

With 25 strains belonging to 12 species of the genus Bacillus, the base composition of DNA, the susceptibility to bacteriophages, and the ability to transform Bacillus subtilis strain Marburg were studied. Analyses of phage DNAs were also performed. The results were as follows: (1) The DNA base compositions were not uniform even among strains belonging to one taxonomic species. (2) The DNAs extracted from B. natto, B. megaterium and B. polymyxa could transform genetic traits of B. subtilis Marburg although the frequencies were not equal. (3) The host ranges of some temperate bacteriophages were correlated with the taxonomical data. On these bases, the phylogenetic relatedness of B. subtilis to B. megaterium was discussed.     

对金缕梅科现代分类系统的评述

为了进一步研究金缕梅科的系统与进化,作者详细介绍了该科的分类历史及各个分类系统;根据现代植物系统学研究的原理和方法,着重对金缕梅科的５个现代主要分类系统,Ｈａｒｍｓ（１９３０）,张宏达（１９７３,１９７９）,Ｂｏｇｌｅｅｔａｌ．（１９８０）,Ｅｎｄｒｅｓｓ（１９８９）和李建华（Ｌｉ,１９９７）进行了详细的分析、比较和评述,在此基础上提出自己的观点,认为李建华的分类系统有一定合理性,但他对个别属的处理和族的划分仍有不妥之处     

Sensitivity of different taxonomic levels of soil Gamasina to land use and anthropogenic disturbances

• 1 The effect of taxonomic level on the sensitivity of bioindicators has been widely investigated in aquatic ecosystems and, to a lesser extent, in terrestrial ecosystems. However, no studies have been conducted on the sensitivity of the different taxonomic levels of soil mites, especially Gamasina, to human activities.
• 2 The present study aimed to assess the sensitivity of different taxonomic levels of soil Gamasina mites to anthropogenic disturbances in Europe and Argentina. We arranged the data from previous projects in a hierarchical system and conducted a study to identify the critical taxonomical levels that had the highest discriminative potential between sites (Europe and Argentina) or management types (forests, grasslands, fallows, succession, recultivation and agricultural sites).
• 3 For the Gamasina community, geographical location was by far more important than the influence of any land use type. The analysis including only the European sites demonstrated that communities belonging to sites subjected to different land uses were also significantly different.
• 4 The species data set provided a clearer separation of sites according to both the geographical and the land‐use gradients than the genus and family data sets. The genus and, to a lesser extent, the family approach may be sufficient to elucidate the influence of great geographical differences and also of certain land uses (e.g. grasslands from the forests and arable sites).
• 5 Species presence/absence data provided valuable information in our analyses, although the use of quantitative data yielded a clearer separation of sites.

     

Occurrence patterns of Afrotropical ticks (Acari: Ixodidae) in the climate space are not correlated with their taxonomic relationships

Foci of tick species occur at large spatial scales. They are intrinsically difficult to detect because the effect of geographical factors affecting conceptual influence of climate gradients. Here we use a large dataset of occurrences of ticks in the Afrotropical region to outline the main associations of those tick species with the climate space. Using a principal components reduction of monthly temperature and rainfall values over the Afrotropical region, we describe and compare the climate spaces of ticks in a gridded climate space. The dendrogram of distances among taxa according to occurrences in the climate niche is used to draw functional groups, or clusters of species with similar occurrences in the climate space, as different from morphologically derived (taxonomical) groups. We aim to further define the drivers of species richness and endemism at such a grid as well as niche similarities (climate space overlap) among species. Groups of species, as defined from morphological traits alone, are uncorrelated with functional clusters. Taxonomically related species occur separately in the climate gradients. Species belonging to the same functional group share more niche among them than with species in other functional groups. However, niche equivalency is also low for species within the same taxonomic cluster. Thus, taxa evolving from the same lineage tend to maximize the occupancy of the climate space and avoid overlaps with other species of the same taxonomic group. Richness values are drawn across the gradient of seasonal variation of temperature, higher values observed in a portion of the climate space with low thermal seasonality. Richness and endemism values are weakly correlated with mean values of temperature and rainfall. The most parsimonious explanation for the different taxonomic groups that exhibit common patterns of climate space subdivision is that they have a shared biogeographic history acting over a group of ancestrally co-distributed organisms.