挂榜山小鲵精子形态结构研究

应用扫描电镜和透射电镜对挂榜山小鲵(Hynobius guabangshanensis)精子的超微结构进行观察和研究.结果表明:1)挂榜山小鲵的精子形态具有小鲵科精子的共同特征:头部细直、有锥形顶体;颈部短而不明显,尾部细长、有波动膜;2)该种小鲵的精子超微结构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;3)除精子全长(194.1±7.15μm)在小鲵科物种中属于中等外,挂榜山小鲵和本科其他物种的精子在形态量度学方面差异明显:其头部占全长的比例(22.98%)比其他已知小鲵科的物种都低,尾部占全长的比例(65.79%)比其他小鲵科物种都高.     

中国两栖动物保护需求总述

通过对中国两栖动物物种生物多样性现状的全面分析, 与世界许多国家相比, 中国是一个重要的全球优先保护地区. 横断山区、南岭山区和武夷山区3个区域的两栖动物物种多样性特别丰富. 有尾两栖类物种较无尾类受胁程度更高. 几个物种数相对较少的铃蟾科、隐腮鲵科、小鲵科和蝾螈科显示出了高的受胁倾向. 像世界其它地方一样, 高海拔地区溪流繁殖的森林物种受胁程度更高. 对中国两栖动物而言, 生境丧失、污染和过度捕捉是最主要的致危因素. 过度捕捉虽然影响不如生境丧失深远, 但它更可能导致一个物种种群的快速衰落. 针对5个方面的保护挑战, 提出了优先研究领域和保护行动方面的建议.     

挂榜山小鲵线粒体DNA COⅠ基因及D-loop区序列研究

研究克隆了挂榜山小鲵COⅠ基因及D-loop区全长,结果显示挂榜山小鲵COⅠ基因及D-loop区全长分别为1 551 bp和803 bp.运用MEGA4.0软件P-distance法分别比较COⅠ基因及D-loop区小鲵科19个物种的遗传距离,结果显示挂榜山小鲵与小鲵属遗传距离比与小鲵科其它属物种的小,并且挂榜山小鲵与Zhang et al(2006)提交的中国小鲵相应序列的遗传距离几乎为0,构建了MP分子系统发生树也显示挂榜山小鲵与小鲵属同属一个分支,且与Zhang et al提交的中国小鲵聚为一小支.通过以上分析认为挂榜山小鲵属于小鲵科小鲵属,这与传统分类学方法一致.     

秦巴拟小鲵在河南的发现及地理分布探讨

报道了采自河南省内乡县的一种小鲵科标本,经形态学鉴定以及DNA序列比对,确定为秦巴拟小鲵(Pseudohynobius tsinpaensis)。内乡是该物种已知分布区的东限,与已知分布点相差3个经度,呈间断分布。秦巴拟小鲵在内乡的发现可为探讨小鲵科动物的起源和演化提供重要的动物地理学依据。     

中国小鲵的核型

中国小鲵(Hynobius chinensis)被描述于116年前,我国学者于2005年在模式产地湖北宜昌再次采到标本,至此该物种的有效性得以确认。以2007年采于模式产地的中国小鲵胚胎为材料,采用Giemsa染色方法,对中国小鲵的核型进行了分析。结果表明,中国小鲵的二倍体染色体数为56,28对染色体按大小和形状可以分为4组:第一组,包括Nos.1～9,由大型m,sm,st染色体组成;第二组为中型双臂染色体组,由Nos.10～13组成,包含m,sm染色体;第三组,包括Nos.14～18,由小型m染色体组成;第四组,包括Nos.19～28,由小型t染色体组成。与小鲵属其他物种相比,中国小鲵核型与具染色体数为2n=56的类群核型大致相同,差异出现在染色体分组和相应染色体着丝点类型上。     

中国小鲵科属、种分类变更的回顾

小鲵科为亚洲特有的有尾两栖动物,是现生有尾目10科中第三大科.中国是小鲵科动物属、种分布的主要区域,且研究其分类历史较久,学者较多,故导致学术观点差异较大.本文对中国小鲵科分类地位发生变更的部分属(巴鲵属Liua、拟小鲵属Pseudohynobius、肥鲵属Pachyhynobius)、种(秦巴巴鲵L. tsinpaensis、满洲小鲵Hynobius mantchuricus、豫南小鲵H. yunanicus、弱唇褶山溪鲵Batrachuperus cochranae和太白山溪鲵B. taibaiensis)的变更历史进行回顾,旨在为小鲵科动物的分类提供一个清晰的背景知识.     

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     

中国拟小鲵属(有尾目,小鲵科)一新种记述

在比较和研究拟小鲵属已知物种黄斑拟小鲵、水城拟小鲵后,确定贵州省绥阳县宽阔水所产拟小鲵为1新种,即宽阔水拟小鲵Pseudohynobius kuankuoshuiensis.新种与黄斑拟小鲵近似,但新种体尾背面黄斑近圆形,头长与头宽之比大于1.55,可与之区分.新种与水城拟小鲵P.shuichengensis相似,但新种体尾及四肢背面有黄色斑块,四肢贴体相向时掌、踱部前半不重叠,而极易与之相区别.     

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.     

新疆北鲵的种群现状及保护对策

新疆北鲵RanodonsibiricusKessler,1866只产于中国新疆温泉县和哈萨克斯坦两国边境山区极狭窄区域,数量亦稀少,是新疆产唯一有尾两栖类。该种在小鲵科的分类、系统演化等方面有重要学术研究价值,已被列人国际保护自然和自然资源联合会红皮书和前苏联红皮书。过去一个多世纪     

Relationships between species richness of vascular plants and terrestrial vertebrates in China: analyses based on data of nature reserves

The relationship between plant diversity and animal diversity on a broadscale and its mechanisms are uncertain. In this study, we explored this relationship and its possible mechanisms using data from 186 nature reserves across China on species richness of vascular plants and terrestrial vertebrates, and climatic and topographical variables. We found significant positive correlations between species richness in almost all taxa of vascular plants and terrestrial vertebrates. Multiple regression analyses indicated that plant richness was a significant predictor of richness patterns for terrestrial vertebrates (except birds), suggesting that a causal association may exist between plant diversity and vertebrate diversity in China. The mechanisms for the relationships between species richness of plants and animals are probably dependent on vertebrate groups. For mammals (endothermic vertebrates), this relationship probably represents the integrated effects of plants on animals through trophic links (i.e. providing foods) and non-trophic interactions (i.e. supplying habitats), whereas for amphibians and reptiles (ectothermic vertebrates), this may be a result of the non-trophic links, such as the effects of plants on the resources that amphibians and reptiles require.     

中国濒危鱼类、两栖爬行类和哺乳类的地理分布格局与优先保护区域——基于《中国濒危动物红皮书》的分析

《中国濒危动物红皮书》依据我国动物所面临的濒危,对我国濒危动物的濒危等级划分,种群现状,致危因素和保护措施等进行了描述说明,首批收录了535种濒危动物。本文以《中国濒危动物红皮书》中所收录的352种濒危脊椎动物（不含鸟类（以下简记为“濒危植物”）为研究对象,整理统计了现有濒危物种的分布资料,在GIS支持下,对中国濒危动物的地理分布进行了研究。结果表明,中国濒危动物物种呈明显的集聚分布,最密集的地区是横断山区,海南岛,西双版纳和云贵高原;而在华北平原,内蒙古东部,黄土高原和东北平原等地区出现大片空白区。影响濒危动物分布的主要因素有热量和水分条件,地形条件等自然条件以及历史开发,人为破坏等人文条件。山地因地形屏障作用而保留了较多的古老物种,其较为复杂的环境因子也有益物种的生存,因而物种丰富度较高。大多数动物对于水分和热量的依赖性较强,因此水热条件对其分布的限制作用十分明显。人为破坏较为严重的地区,濒危物种稀少;污染,开荒等引起的环境问题对于现存动物的威胁很。运用Dobson排除算法得到云南勐腊县等9个县分布有168种濒危动物,占全国总数（海生种类及仅分布于台湾和香港的特有种除外）的51．5％,而其土地面积之和仅为全国陆地总面积的0．9％。而云南勐腊县等94个县市就分布有中国所有的濒危动物。这些地区是我国生物多样性保护应该优先考虑的地方。     

Vertebrate Dissimilarity Due to Turnover and Richness Differences in a Highly Beta-Diverse Region: The Role of Spatial Grain Size,Dispersal Ability and Distance

We explore the influence of spatial grain size, dispersal ability, and geographic distance on the patterns of species dissimilarity of terrestrial vertebrates, separating the dissimilarity explained by species replacement (turnover) from that resulting from richness differences. With data for 905 species of terrestrial vertebrates distributed in the Isthmus of Tehuantepec, classified into five groups according to their taxonomy and dispersal ability, we calculated total dissimilarity and its additive partitioning as two components: dissimilarity derived from turnover and dissimilarity derived from richness differences. These indices were compared using fine (10 x 10 km), intermediate (20 x 20 km) and coarse (40 x 40 km) grain grids, and were tested for any correlations with geographic distance. The results showed that total dissimilarity is high for the terrestrial vertebrates in this region. Total dissimilarity, and dissimilarity due to turnover are correlated with geographic distance, and the patterns are clearer when the grain is fine, which is consistent with the distance-decay pattern of similarity. For all terrestrial vertebrates tested on the Isthmus of Tehuantepec both the dissimilarity derived from turnover and the dissimilarity resulting from richness differences make important contributions to total dissimilarity, and dispersal ability does not seem to influence the dissimilarity patterns. These findings support the idea that conservation efforts in this region require a system of interconnected protected areas that embrace the environmental, climatic and biogeographic heterogeneity of the area.     

近40年东北地区陆栖脊椎动物种群数量及其生境变化评估

生物多样性是生态平衡维持和生态过程与功能实现的基础,东北地区是我国乃至全球生物多样性最为丰富的地区之一。为研究和探讨东北地区陆栖脊椎动物种群数量与生境变化之间的关系,利用物种调查数据和生境遥感观测数据,以地球生命力指数、生态系统面积和破碎度等指示性指标,综合评估了近40年东北地区陆栖脊椎动物种群数量及其生境变化。结果表明:1970—2010年,东北地区陆栖脊椎动物种群数量下降了近70.1%,森林脊椎动物种群数量减少了近80.9%,草原和荒漠生态系统脊椎动物种群数量增加了近180.9%。1980—2010年,湿地物种种群数量减少了近75.7%。1980—2015年期间,农业和城镇建设用地增幅分别达到25.2%和32.3%,不断挤占和蚕食着自然生态空间,致使自然生境面积不断减少,减幅约为8.0%。自然生境景观破碎化程度总体呈现加重趋势,尤其是森林生境,破碎化指数增加约42.7%。但是,2005年之后,自然生境景观破碎化程度加重趋势趋缓,与2005年之后脊椎动物种群数量减少幅度减缓趋势一致。森林砍伐、人口增长、城镇化、交通建设等造成的自然生态系统破碎度增加和栖息地质量下降对大型兽类影响比较显著。     

黄河流域被子植物和陆栖脊椎动物丰富度格局及其影响因子

生物多样性的大尺度空间分布格局及其形成机制一直是生态学和生物地理学的核心内容。黄河流域是我国重要的生态屏障, 明确该区域动植物多样性分布格局及其影响因素, 对我国黄河流域生态保护和高质量发展具有重要意义。本研究通过收集黄河流域被子植物和陆栖脊椎动物分布数据, 结合气候、环境异质性和人类活动等信息, 探讨了黄河流域被子植物和陆栖脊椎动物物种丰富度格局及其主要影响因素。结果表明, 黄河流域被子植物和陆栖脊椎动物物种丰富度在区域尺度具有相似的分布格局: 南部山地动植物物种丰富度最高, 而东部高寒区和北部干旱区物种丰富度最低。回归树模型表明, 冠层高度范围和净初级生产力范围分别是黄河流域被子植物和陆栖脊椎动物物种丰富度最重要的预测因子; 当移除空间自相关影响后, 环境异质性和气候因子依然对区域尺度的动植物物种丰富度具有较高且相似的解释度。表明环境异质性和气候共同决定了黄河流域被子植物和陆栖脊椎动物物种丰富度格局, 而人类使用土地面积并不是影响黄河流域动植物物种丰富度格局的主要因子。因此, 在未来的研究中若针对不同区域筛选出更精准的环境驱动因子或选用更多不同类别的环境异质性因子进行分析, 将有助于更深入理解物种多样性格局的成因。     

Structure and function of the hyolingual system in Hynobius and its bearing on the evolution of prey capture in terrestrial salamanders

The Hynobiidae is generally regarded as the most phylogenetically basal and least derived extant family of terrestrial salamanders. As in the other families of terrestrial salamanders, prey capture in the Hynobiidae is accomplished by lingual prehension. In Hynobius, the prey capture system appears to be a mosaic of derived and primitive features. This, in conjunction with previous studies, suggests that the hyolingual systems of all families of terrestrial salamanders have evolved various degrees of specialization since the appearance of the common ancestral condition. We propose that the generalized feeding system for the extant terrestrial salamanders includes a hyolingual skeleton comprised of one basibranchial, one pair of radial or radial-like structures, two pairs of ceratobranchials, two pairs of epibranchials, one pair of ceratohyals, and one urohyal arranged in a configuration similar to that of Hynobius; a simple, sac-like secondary tongue pad; a lift and thrust system of tongue projection; a four-part gape cycle; and a forward head and body surge. Modifications to this general plan, previously described for the disparate families, include various changes in the size, shape, and definition of the tongue pad, changes in the specific types of structures and configurations in the anterior hyolingual skeleton, secondary ossification in the posterior hyolingual skeleton, the appearance of various protrusion, projection, and flipping systems for tongue protraction, simplification of the kinematic gape profile, and loss of the forward head and body surge. The evolutionary trends in these modifications have provided a rich data set from which much phylogenetic information has been inferred. © 1996 Wiley-Liss, Inc.     

Eye size variation reflects habitat and daily activity patterns in colubrid snakes

The functioning of the vertebrate eye depends on its absolute size, which is presumably adapted to specific needs. Eye size variation in lidless and spectacled colubrid snakes was investigated, including 839 specimens belonging to 49 genera, 66 species and subspecies. Variations of adult eye diameters (EDs) in both absolute and relative terms between species were correlated with parameters reflecting behavioral ecology. In absolute terms, eye of arboreal species was larger than in terrestrial and semiaquatic species. For diurnal species, EDs of terrestrial species do not differ from semiaquatic species; for nocturnal species the ED of terrestrial species is larger than fossorial species but not different from semiaquatic species. In relative terms, ED did not differ significantly by habitat for diurnal species. Although the ED of terrestrial species is larger than fossorial species there were no differences for nocturnal species between semiaquatic and fossorial snakes. In contrast to other vertebrates studied to date, colubrid EDs in absolute and relative terms are larger in diurnal than in nocturnal species. These observations suggest that among colubrid snakes, eye size variation reflects adaptation to specific habitats, foraging strategies and daily activities, independently of phylogeny. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.     

Commensal and mutualistic interactions among terrestrial vertebrates

Although overlooked in many field studies, commensal and mutualistic interactions occur frequently between species of terrestrial vertebrates. Potential advantages for individuals in mixed-species associations are very diverse, and include reduction in parasite load, reduced risk of predation, and increased access to food and other resources. Recent theoretical and experimental studies reveal the prevalence of such interactions among terrestrial vertebrates, and also confirm their importance within communities thought previously to be dominated by interspecific competition.