中国石龙子成熟精子的超微结构

利用透射电镜观察中国石龙子附睾成熟精子的超微结构。顶体囊前部扁平、由皮质和髓质组成 ,穿孔器中度倾斜、顶端尖 ,穿孔器基板塞子状 ,细胞核长形 ,核内小管缺 ,核前电子透亮区小 ,核肩圆 ,核陷窝锥形。颈段具片层结构 ,近端中心粒和远端中心粒的长轴呈直角 ,9束外周致密纤维与远端中心粒相应的 9束三联微管相联 ,向后与轴丝相应的 9束双联微管相联 ,中央纤维与 2个中央单微管相联。中段短 ,多层膜结构缺 ,含有线状嵴的柱状线粒体 ,不规则卵状致密体组成不连续的环状结构 ,纤维鞘伸入中段 ,具终环。线粒体与环状结构的模式为 :rs1 /mi1 ,rs2 /mi2 ,rs3/mi3,rs4 /mi4。主段前面部分具薄的细胞质颗粒区。纤维 3和 8至主段前端消失。轴丝呈“9 2”型。中国石龙子精子超微结构具有塞子状的穿孔器基板、致密体形成不连续的环状结构和纤维鞘始于ms2等特征与巨石龙子群和蜓蜥 -胎生群不同。没有发现石龙子科精子的独征     

水热环境对中国石龙子孵化卵、孵化成功率及孵出幼体特征的影响

用 8种水热条件孵化中国石龙子 (Eumeceschinensis)卵 ,观测孵化卵质量变化、胚胎利用卵内物质和能量及孵出幼体特征。孵化卵因净吸水增重 ,卵增重与入孵卵质量、孵化温度和基质湿度有关。孵出幼体湿重的处理间差异主要是因为幼体水分含量不同。温度显著影响孵化期、孵化卵吸水量、胚胎利用卵内物质和能量几乎所有被检的幼体特征 ;温度甚至影响胚胎动用卵壳无机物。然而 ,在 2 4～ 32℃范围内 ,温度对卵孵化成功率无显著的影响。 32℃孵出幼体比较低于此温度的孵出幼体发育差 ,表现为躯干小、未利用的卵黄多。此外 ,32℃孵出幼体的运动表现比低温孵出幼体差 ,表现为特定体长 (snout ventlength ,SVL)的疾跑速小于低温孵出幼体 ,表明高温孵化卵对孵出幼体的运动能力有不利的影响。潮湿基质中孵出幼体的体长和尾长大于干燥基质中孵出的幼体 ,并特征性地具有较小的剩余卵黄。 2 4℃胚胎发育能耗较大 ,胚胎从卵壳动用的无机物较少。温度影响孵出幼体的体形和头部大小 ,30℃孵出幼体的尾长最大 ,32℃孵出幼体的头部最小。基质湿度对孵出幼体的体形和头部大小无显著的影响。温度对孵出幼体特征的影响与湿度的影响无关。孵化水热环境诱导的幼体大小、质量和形态差异可能对幼体的生存和适应性具有重要的影响。 2     

Characterization of 21 microsatellite marker loci in the prehensile‐tailed skink (Corucia zebrata)

Twenty‐one polymorphic microsatellite loci were isolated and characterized from the genome of the prehensile‐tailed skink (Corucia zebrata). The markers were screened using a set of 16 individuals from the collection of the Philadelphia Zoo. The corresponding characterization indicated significant levels of heterozygosity and information potential for use in future studies. These markers will be a valuable tool in analysing the paternal contributions in twin birth questions and for population genetic studies in wild populations.     

四种内外因素导致的中国石龙子运动表现的种群内变异

设计四项实验研究四种内外因素(环境温度、怀卵、摄食和断尾) 导致的中国石龙子(Eumeces chinen sis) 运动表现种群内变异。环境温度通过影响体温而影响石龙子的运动表现。两性成体疾跑速均具有在低体温范围内随体温升高而加快、在高体温范围内随体温升高而降低的一般模式。怀卵雌体和成年雄体使平均疾跑速达到最大值的体温分别是29℃和30℃。在任何体温下成年雄体的疾跑速均大于怀卵雌体, 表明怀卵对母体运动有不利的影响并相对地增加了雌体繁殖代价。怀卵雌体和成年雄体的最大持续运动距离无显著差异; 体温对最大持续运动距离有显著影响, 且主要与低体温下最大持续运动距离较小有关。性别与体温相互作用对最大持续运动距离有显著影响。怀卵雌体和成年雄体的疾跑速和最大持续运动距离呈显著的正相关。以性别为因子的ANCOVA去除最大持续运动距离差异的影响后发现, 成年雄体的疾跑速仍大于怀卵雌体。27℃和30℃平均体温下的摄食实验进一步证实怀卵雌体疾跑速小于成年雄体, 但前者最大持续运动距离大于后者。该实验同时显示禁食石龙子的疾跑速和最大持续运动距离大于摄食石龙子, 各因子相互作用对最大持续运动距离的影响显著,仅性别与摄食相互作用对疾跑速有边缘性显著影响。27℃和30℃平均体温下的尾自切     

The long unknown: Rediscovery of the long sunskink,Lampropholis elongata (Squamata: Scincidae)—After almost a decade,and after 50 years of data deficiency

Conservation management cannot proceed in the absence of the basic ecological data necessary to develop conservation strategies for a species. Species considered Data Deficient and possibly extinct are poorly known, and are often overlooked in conservation planning. This is despite a growing body of evidence indicating that Data Deficient species are more likely to be threatened by extinction compared to well-studied taxa. Hence, there is an immediate need to resolve data deficiency, and to search for species that are possibly extinct. Here, we conducted the first systematic search for a Data Deficient Australian skink, Lampropholis elongata (long sunskink), which prior to our study, had not been seen for approximately 9 years. A combination of pitfall trapping and active searches was used in attempt to detect the species. We rediscovered L. elongata at four sites within its known distribution on the southern edge of the New England Tablelands Bioregion in New South Wales, Australia. Our findings suggest that the species can be detected relatively easily using active survey methods, especially by inspecting tussock bases. We further highlight that areas of high canopy openness and high cover of Poa sieberiana (grey tussock-grass) appear to be key habitat for the species.     

Isolation and characterization of microsatellite loci from the coppertail skink (Ctenotus taeniolatus)

We report on the isolation and characterization of eight microsatellite markers for the coppertail skink (Ctenotus taeniolatus). From a sample of 27 individuals, the number of alleles per locus ranged from seven to 13 and observed and expected heterozygosities ranged from 0.714 to 0.818 and from 0.738 to 0.899, respectively. These loci will be used to assess anthropogenic disturbance on coppertail skink populations. These are the first microsatellites reported for the genus Ctenotus, despite being the most speciose genus of lizards in Australia.     

蓝尾石龙子的头部两性异形和食性

通过测量头、体大小和胃检研究浙江泰顺产蓝尾石龙子 (Eumeceselegans)个体发育过程中两性异形和食性的变化。蓝尾石龙子成体个体大小和头部大小的两性差异显著 ,雄性大于雌性。不同发育阶段雌性头长与SVL的线性回归斜率无显著差异 ,头宽与SVL线性回归斜率的差异显著 ,成体和SVL <5 0mm幼体头宽随SVL的增长速率显著小于SVL为 5 0 - 6 9mm的幼体。雄性头部相对于SVL呈加速式异速生长。两性比较发现 :雌雄幼体头长和头宽随SVL的增长速率无显著差异 ,SVL <5 0mm幼体特定SVL的头长和头宽无显著的两性差异 ,但SVL为 5 0 - 6 9mm的雄性幼体头长和头宽大于SVL相同的雌性幼体 ;雄性成体头长和头宽随SVL的增长速率显著大于雌性。SVL <5 0mm的雌性幼体头部相对小于SVL为 5 0 - 6 9mm的同性幼体 ,性成熟雌体头部相对小于SVL为 5 0 - 6 9mm的同性幼体。雌性幼体、雄性幼体、雌性成体和雄性成体食物生态位宽度分别为 12 3、 12 5、 4 8和 14 4。雌雄幼体食物生态位重叠度最高 ,雌雄成体食物生态位重叠度次之 ,成体与幼体食物生态位重叠度较小。成体摄入食饵的大小 (用胃内完整食物长度的平均值表示 )和变化范围大于幼体。两性成、幼体摄入的食饵大小差异显著。两性个体摄入的食饵大小均与其SVL呈正相关 ,表明较大     

Ten polymorphic microsatellites from freshwater pearl mussel,Hyriopsis cumingii

Freshwater pearl mussel, Hyriopsis cumingii, is the most economically important mussel species in China. Due to overexploitation and changes of water quality, H. cumingii is facing serious population decline and local extinction. We have isolated and characterized 10 polymorphic microsatellite loci from a genomic DNA library enriched for CA and AG repeats with the aim of developing a set of codominant DNA markers for analysing genetic diversity and population structure of this species. The average allele number of the 10 markers was 7.8 per locus, ranging from two to 16 in 24 unrelated individuals. Nine of 10 markers conformed to Hardy–Weinberg equilibrium and inherited independently, suggesting these microsatellites could be useful for studying population genetics, designing conservation strategies and developing breeding programs.     

中国石龙子母体孕期调温诱导幼体表型: 母体操纵假说的实验检测

卵胎生是由卵生繁殖模式通过逐渐增加卵滞留和胚胎在母体子宫内发育的时间进化而来的繁殖模式。有鳞类爬行动物(蜥蜴和蛇)有着较高的繁殖模式多样性,因而是研究卵胎生繁殖模式进化及其适应意义的理想动物模型。至今对于卵胎生进化的选择压力尚无定论,目前有3种关于卵胎生进化的假说受到学者的关注,其中母体操纵假说最受关注但尚未得到充分的检测。研究继1995年母体操纵假说提出之后,以栖息于温带气候环境下的卵生中国石龙子(Eumeces chinensis)为模型动物检测该假说。37条中国石龙子怀卵母体采自浙江丽水市郊。将怀卵母体分置于3个热处理中,其中12条母体提供每日14 h光照时间,13条母体提供10 h光照,其余12条母体没有任何调温机会(体温随室内环境温度而改变)。结果显示:怀卵母体选择体温向下漂移。3种处理下的雌体繁殖特征没有显著差异。长、短调温组下母体产卵时间要早于非调温组母体,但新生卵的胚胎历期没有显著差异。用5种热处理孵化卵,孵化温度分别为:1=室内波动温度孵化;2=27℃;3=24—30℃;4=22—32℃(3和4孵化处理中,孵化箱内的温度每隔1d改变1次,即卵分别在22和24℃孵化24 h,随后在32和30℃孵化24 h,每2d循环1次直至孵出);5=在实验室后院内模拟石龙子野外巢址孵化。结果显示:孵出幼体的体长、腹长和头部大小(头长和头宽)在3个母体热处理间存在显著差异,其他形态学特征不存在母体热处理间的显著差异;孵化温度以及孵化温度和母体热处理的交互作用对所有的幼体形态学特征均无显著影响。孵化温度以及孵化温度和母体热处理的交互作用对幼体疾跑速和最大持续运动距离无显著影响;但不同的母体热处理显著影响幼体疾跑速和最大持续运动距离。研究结果不仅为\"热变异对在一定孵化温度范围内表型无显著变化的物种的幼体表型没有重要的修饰作用\"这一假说提供了有力证据,并且支持母体操纵假说的两个主要预测:雌体在孕期通过体温漂变行为提供体内胚胎发育的最适热环境,而由母体调温行为诱导的后代表型的变异将增强后代的适合度。     

Eight microsatellite markers for the San Esteban chuckwalla,Sauromalus varius

We characterize eight polymorphic microsatellite loci for the San Esteban chuckwalla, Sauromalus varius, which are being used as markers in a study of the genetic results from a decade of captive breeding in this endangered species. Observed heterozygosity estimates for S. varius ranged from 0.00 to 0.30, whereas expected heterozygosity estimates ranged from 0.06 to 0.58.