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1.
Hwang DS  Lee JS 《Mitochondrial DNA》2012,23(4):301-302
We sequenced the complete mitochondrial genome from the boreal digging frog Kaloula borealis. The genome sequence was 17,173 bp in size, and the gene order and contents were identical to those of previously reported amphibian mitochondrial genomes. Of 13 protein-coding genes (PCGs), 5 genes (CO2, ATPase 6, CO3, ND3, and ND4) had incomplete stop codons. Also ND1 gene used GTG as a start codon, while CO1 and ND5 genes used AGG as a stop codon. The base composition of K. borealis mitogenome showed a strong anti-G bias (6.11%) on the 3rd position of PCGs.  相似文献   

2.
目的探讨北方狭口蛙(Kaloula borealis)消化道5-羟色胺细胞的分布密度规律和形态学特点。方法免疫组织化学SABC法鉴别和定位雌雄各6只北方狭口蛙食管、贲门、胃体、幽门、十二指肠、空肠、回肠和直肠的5-羟色胺细胞。结果5-羟色胺细胞的分布密度高峰位于胃幽门部,胃体和十二指肠其次,贲门最低。开放型和闭合型细胞的比值从食管至直肠呈”V”形分布,胃幽门部为比值的最低点。食管、贲门和肠道各段的5一羟色胺细胞以开放型细胞为主,胃体开放型和闭合型细胞的数量几近相等,胃幽门部以闭合型细胞为主。结论北方狭口蛙消化道5-羟色胺细胞的分布型和形态学特点与其他两栖动物既有相同点,也有自身的独特性,这可能与其食性和善于穴居掘土的生活方式有关。  相似文献   

3.
Invasive species are one of the most serious threats to amphibian populations. We investigated the effects of two invasive (Pomacea canaliculata and Physella acuta) and one native (Radix sp.) snail species on five species of wetland-breeding frogs in Hong Kong. We quantified embryonic survivorship and determined whether particular attributes of amphibian egg masses influenced consumption by snails. P. canaliculata preyed on four of the species, consuming >90 % of eggs of Microhyla fissipes and Fejervarya limnocharis, nearly 70 % of eggs of Kaloula pulchra, approximately 40 % of eggs of Duttaphrynus melanostictus, but no eggs of Polypedates megacephalus. P. acuta and Radix sp. consumed only the eggs of K. pulchra, but those eggs were probably non-viable. This study shows that P. canaliculata, which occurs at high densities in tropical East Asia, may be an important predator of amphibian eggs. Future research should evaluate their effects on amphibian populations, community structure, and food web dynamics.  相似文献   

4.
全球范围内两栖类的种类和数量急剧下降,栖息地面积减少和质量下降为重要原因之一.修复和重建两栖类栖息地是恢复两栖类种类和数量的重要手段.在城市化进程中,构建适宜的两栖类栖息地对两栖类的保护尤为关键.本研究选取上海市闵行区浦江镇的鲁汇苗木基地,于2014年5月-2016年9月开展两栖类栖息地的构建技术及效果评估研究.针对上海市常见的5种两栖类的生境需求,经过地形地貌改造、水系沟通调整和植被恢复等生态工程措施,构建了19 hm2两栖类栖息地.为评估两栖类栖息地的保护效果,采取样线法,选取5条100 m×5 m的调查样线,于多数两栖类的繁殖期(5-6月)和非繁殖期(8-9月)各调查1次,对比分析改造前(2014年)和改造后(2016年)两栖类的种类和数量.调查发现,改造前的繁殖期记录到两栖类4种,密度为(164.0±63.7) ind·hm-2;非繁殖期4种,密度为(160.0±29.7) ind·hm-2;改造后的繁殖期5种,密度为(560.0±159.3) ind·hm-2;非繁殖期5种,密度为(628.0±186.2) ind·hm-2.结果表明,通过构建适宜的两栖类栖息地,能够显著增加两栖类的种类和数量,具有较好的两栖类保护效果.本研究提出的两栖类栖息地的构建技术,为受损的两栖类栖息地的生态修复和重建以及城市林绿地的优化改造提供了参考案例.  相似文献   

5.
As a process affecting animal communities, urbanization has been the subject of numerous studies. However, amphibians are still among the least studied vertebrate groups in urbanized landscapes. Generally, it has been found that the process of loss of amphibian diversity is nonrandom, with species from older evolutionary lines at greater risk. Regional data on amphibian assemblages in urban areas is a very useful tool for assessing how these assemblages react to changes.The aim of the present paper is to assess the diversity of amphibians in Polish cities based on data in the relevant literature, exploring different metrics (e.g., taxonomic, functional, and evolutionary diversity) calculated in amphibian species assemblages. We used data from 18 articles (including grey literature), characterized by comparable research methods and published between 1999 and 2017.Overall, amphibian species richness (ASR) amounted to an average of 9 species, ranging from 5 to 11 species per city. The higher species richness occurred in Białystok in North-west of Poland. Functional evenness (FEve), evolutionary distinctiveness (ED sum), and functional richness (FRic) were strongly positively correlated with ASR. However, ED mean was not significantly correlated with the total number of species in the community. Three taxa, the hybridogenetic water frogs Pelophylax esculentus complex, the common toad Bufo bufo, and the common frog Rana temporaria, occurred in all analyzed amphibian assemblages. Our study is one of the first attempts to compare urban amphibian assemblages, using different and complementary diversity metrics on a large spatial scale. In conclusion, we highlight that urban areas play an important role for conservation of amphibians, because they support amphibian assemblages characterized by a high level of overall diversity.  相似文献   

6.
云南省发现弄岗狭口蛙   总被引:1,自引:0,他引:1  
2018年6月,在位于云南省文山壮族苗族自治州的文山国家级自然保护区(23°21′41″N,104°50′26″E,海拔1 300 m)采集到无尾目(Anura)姬蛙科(Microhylidae)狭口蛙属(Kaloula)标本3号,包括雄性成体标本1号和雌性成体标本2号,并对相应形态特征进行了测量,雄性头体长为35.79mm,雌性头体长为48.01 mm和42.78 mm。根据形态特征比较发现,该种群的标本皮肤光滑,背部呈橄榄绿色,有不规则的深绿色斑纹,指端平切且具两排小乳突,雄性胸部有小柠檬黄色斑点,雄性全蹼,雌性为1/3蹼,与采集自弄岗国家级自然保护区的弄岗狭口蛙(K. nonggangensis)地模标本(海拔186 m)的形态鉴定特征基本一致,仅体色和体型大小稍有差异。基于16S rRNA基因片段进行系统发育分析表明,这些标本与弄岗狭口蛙模式产地标本聚在一起,共享同一单倍型。可以确定所采集的3号标本均为弄岗狭口蛙,为云南省两栖纲分布新记录物种。新发现的种群分布于中高海拔处,较地模标本的低海拔分布记录有较大的拓展。该物种的发现说明,云南东南部与广西西南部的喀斯特地区具有相似的物种...  相似文献   

7.
贵州省两栖动物新纪录——白线树蛙   总被引:2,自引:0,他引:2  
张雷  陈红  曾强  吕红军 《动物学杂志》2010,45(3):159-162
2009年8月,在实验室整理大树蛙(Rhacophorus dennysi)标本时,发现有两个标本形态特征不同。经鉴定,该标本为白线树蛙(R.leucofasciatus),为贵州省两栖动物新纪录。  相似文献   

8.
9.
This retrospective study examines the geographic and temporal distribution of bat species submitted for rabies testing in South Carolina (USA) from 1970 to 1990. Histories of human or animal exposures to rabid and nonrabid bats submitted during this time period were compared. Two hundred and thirty-one bats were found to be rabid from the 2,657 bats submitted over this 20 yr period. The two species most frequently submitted for testing were Lasiurus borealis with 785 specimens (30% of the total) and Nycticeius humeralis with 607 specimens (22% of the total). Lasiurus borealis also had the highest prevalence of rabies (18%) while N. humeralis had the lowest prevalence (3%). Fifty-one percent (1,259) of the bats received for testing were submitted from June through August. The majority (54%) of rabid bats were received from August through October.  相似文献   

10.
The persistence of pond-breeding amphibian populations is influenced on different spatial scales ranging from the individual breeding pond to surrounding habitat patches to landscape clusters of breeding pond populations. The connectivity among breeding ponds as well as the availability of suitable terrestrial habitats surrounding the ponds plays a major role in long-term viability of amphibian species. Besides road traffic and urban structures agricultural land activity can disrupt landscape connectivity through the use of pesticides, fertilizers and physical activity such as tillage. We developed an expert-based model to assess the impact of agricultural management measures on the migration area and terrestrial habitat availability for seven amphibian species. The model is based on a Habitat Suitability Index to identify suitable terrestrial habitats and includes a landscape permeability approach. Size of migration areas, connectivity of breeding ponds and number of reachable terrestrial habitats were modeled considering species-specific migration ranges and habitat preferences. We consider how pesticides application might lead to fragmentation and isolation of amphibian breeding pond populations. Therefore the potential disrupting impact of pesticides was simulated by inflating landscape resistance to medium and high migration cost. One amphibian species showed a decrease of migration area by 48.3% and a decrease of reachable terrestrial habitats by 41.5% at high migration costs. Three additional species showed a decrease of their migration areas between 31.5 and 35.7%. At increased migration cost, some of the investigated populations were isolated at breeding pond level or restricted to pond clusters. Our model could be used to prioritize conservation efforts for pond-breeding amphibians with adequate consideration of agricultural land use and its impact on amphibian migration.  相似文献   

11.
Igawa T  Kurabayashi A  Usuki C  Fujii T  Sumida M 《Gene》2008,407(1-2):116-129
We sequenced the whole mitochondrial (mt) genomes of three neobatrachian species: Japanese tree frog Hyla japonica, Japanese common toad Bufo japonicus, and narrow-mouthed toad Microhyla okinavensis. The gene arrangements of these genomes diverged from that of basal anurans (suborder Archaeobatrachia), but are the same as that of the members of derived frogs (i.e., superfamily Hyloidae and Ranoidae in suborder Neobatrachia), suggesting the one-time occurrence of a gene rearrangement event in an ancestral lineage of derived anurans. Furthermore, several distinct repeat motifs including putative termination-associated sequences (TASs) and conserved sequence blocks (CSBs) were observed in the control regions (CRs) of B. japonicus and H. japonica, while no repeat motifs were found in that of M. okinavensis. Phylogenetic analyses using both nucleotide and amino acid data of mt genes support monophyly of neobatrachians. The estimated divergence time based on amino acid data with multiple reference points suggests that the three living amphibian orders may have originated in the Carboniferous period, and that the divergences of anurans had occurred between the Permian and Tertiary periods. We also checked the influence of the data types and the settings of reference times on divergence time estimation. The resultant divergence times estimated from several datasets and reference time settings suggest that the substitution saturation of nucleotide data may lead to overestimated (i.e., older) branching times, especially for early divergent taxa. We also found a highly accelerated substitution rate in neobatrachian mt genes, and fast substitution possibly resulted in overestimation. To correct this erroneous estimation, it is efficient to apply several reference points among neobatrachians.  相似文献   

12.
腐霉属的一个新种和二个新记录   总被引:1,自引:0,他引:1  
本文报告作者1982—1983年在北京和广东一些地区土壤中用已知方法(余永年,1975)分离到的几种腐霉,其中1个新种(Pythium borealis sp.nov.)、2个国内未报道的种(P.oligandrum和P.myriotylum)和1个已知种的变异株(P.ultimum variant)。文中对以上各菌进行了形态学描述。  相似文献   

13.
The Baltic Sea is the largest brackish water area of the world.On the basis of the data from 16 cruises, we show the seasonaland vertical distribution patterns of the appendicularians Fritillariaborealis, Oikopleura dioica and the cyclopoid copepod Oithonasimilis, in the highly stratified Bornholm Basin. These specieslive at least temporarily below the permanent halocline anduse different life strategies to cope with the brackish environment.The cold-water species F. borealis is abundant in the upperlayers of the water column before the thermocline develops.With the formation of the thermocline abundance decreases andthe specimens outlast higher temperatures below the halocline.Distribution and strategy suggest that F. borealis might bea glacial relict species in the Baltic Sea. Although Oikopleuradioica is only abundant during summer, O. similis is presentall year round. Both species have in common that their verticaldistribution is restricted to the waters below the halocline,most likely due to their requirements of higher salinities.We argue that the observed strategies are determined by ecophysiologicalconstraints and life history traits. These species share anomnivorous feeding behaviour and the capability to utilise aspectra of small particles as food. As phytoplankton concentrationis negligible below the halocline, we suggest that these speciesfeed on organic material and heterotrophic organisms that accumulatein the density gradient of the halocline. Therefore, the deephaline waters in the Baltic Sea represent a habitat providingshelter from predation and food supply for adapted species thatallows them to gather sufficient resources and to maintain populations.  相似文献   

14.
We tested two hypotheses about boundary units and seven about environmental control of species diversity in order to explain geographical trends in the richness of amphibian species in the Mediterranean watershed of the southern coast of the Iberian Peninsula. The number of amphibian species tends to decrease from west to east. The longitudinal trend in the richness of amphibian species actually occurs on passing from one basin to another, but there is not any longitudinal trend within the basins. Multivariate analyses confirmed that the disturbances of episodic river-basin floodings were the principal factor which controls the richness of amphibian species. They explained 94.8% of the observed variations in the richness of amphibian species in this area, according to the intermediate disturbance hypothesis.We propose hydrographic basins as suitable geographical units for further biogeographical analysis and for considering the role of disturbances produced by floods in the environmental control of species diversity.  相似文献   

15.
Liverwort Pellia borealis is an allopolyploid species that originated after the hybridization and chromosome doubling of two cryptic species; Pellia epiphylla species N and Pellia epiphylla species S. A sequence comparison of chloroplast tRNAUCCGly, tRNAUUULys gene introns, the mitochondrial tRNAGCUSer gene intron, and the first intron of the coxIII gene in the case of three liverwort species studied revealed that the chloroplast and mitochondrial sequences are identical in P. borealis and P. epiphylla species N but different from homologous P. epiphylla species S sequences. Both mitochondria and chloroplasts of P. borealis were thus inherited from one parent- P. epiphylla species N. Studies on 14 different populations of P. borealis gave the same result. These are the first data on organellar transmission in liverworts, the earliest land plants. Moreover, we show that the intron sequences of some organellar genes, until now not used in any systematic studies, could be very good markers in studying taxonomic relationships in closely related species and reconstructing historical events.  相似文献   

16.
Baker WK 《Genetics》1980,94(3):733-748
Previous studies on linkage disequilibrium involving four tightly linked genes that code for the alpha-esterases of Drosophila montana suggest that these loci arose from a primitive esterase gene by gene duplication, followed by tandem duplication (Roberts and Baker 1973). We have examined the esterase variants in the closely related species, lacicola, flavomontana and borealis. These studies reveal that borealis has only a single esterase locus, and flavomontana may have only two loci. Cytological studies, using aceto-orcein staining and Hoechst fluorescence of squashes of ganglion chromosomes, reveal acrocentric Y chromosomes for all six species of the montana phylad, with the exception of borealis, which has the primitive rod-shaped Y chromosome. These studies provide evidence against the hypothesis (Stone, Guest and Wilson 1960) that borealis and flavomontana are derived from montana, but support Throckmorton's (1978) conclusion of the early divergence of the former two species. This phylogenetic relationship supports our contention that the difference in the number of esterase genes with active alleles between borealis and montana is based on an increase in the number of genes coding for the alpha-esterases, rather than the retention in borealis of three genes with null alleles.  相似文献   

17.
Abstract: Standardized, effective sampling methods are required to monitor amphibian population trends and community composition. Funnel traps have been used to ostensibly estimate species richness and relative abundance of larval amphibians. We tested whether funnel traps can be used to provide unbiased estimates of amphibian community composition in playa wetlands by comparing seining—dip netting and passive funnel-trapping results. Plains spadefoots (Spea bombifrons) were more prone to be captured in funnel traps whereas New Mexico spadefoots (S. multiplicata) were less likely captured by funnel traps than by seines and dip nets. In playas funnel traps should be used only for collecting specimens and not for estimating amphibian community composition.  相似文献   

18.
Zvereva EL  Rank NE 《Oecologia》2003,135(2):258-267
Larvae of the leaf beetle Chrysomela lapponica obtain salicyl glucosides (SGs) from the host plant to produce a defensive secretion with salicylaldehyde. In northern Russia, larvae and pupae experience high parasitism by the phorid fly Megaselia opacicornis and tachinid fly Cleonice nitidiuscula. We compared the suitability of the SG-rich Salix borealis and SG-poor S. caprea and S. phylicifolia to Ch. lapponica and tested whether enemy pressure on Ch. lapponica varies among host species that differ in SG content. In the laboratory, survival of Ch. lapponica larvae was higher on S. borealis than on S. caprea and S. phylicifolia, while adult body mass was higher on S. borealis and S. caprea than on S. phylicifolia. In the field, parasitism by both M. opacicornis and Cl. nitidiuscula was greater on beetles from S. borealis than from the SG-poor S. caprea or S. phylicifolia. In a laboratory choice test, the pupal parasitoid M. opacicornis laid similar numbers of eggs on beetles reared on SG-rich and SG-poor willows, suggesting that the host plant-derived defence is not effective against this parasitoid. In a field enemy-exclusion experiment, beetle survival was greatly enhanced by the exclusion of enemies, but survival rates did not differ between S. borealis and S. caprea, although larvae developed faster on S. borealis. On the other hand, parasitism and predation were observed more often on S. borealis than on S. caprea. Thus, beetle larvae perform better but also suffer higher predation and parasitism on S. borealis than on SG-poor willows. Ch. lapponica does not appear to obtain enemy-free space by feeding on SG-rich willow species.  相似文献   

19.
2019年5月18和19日,在贵州赤水桫椤国家级自然保护区金沙沟片区(28°26′12″N,105°59′52″E海拔465m)采集到8只两栖动物标本。形态上,这些标本与模式产地的峨眉角蟾(Megophrys omeimontis)相近。基于528 bp的16S rRNA基因片段构建最大似然系统发育树表明,本次采集的8只标本与峨眉角蟾模式产地标本聚在一起,其遗传距离远小于角蟾属其他物种之间的遗传距离。因此,结合分子系统学分析及形态学比较,确认这些标本为无尾目(Anura)角蟾科(Megophryidae)角蟾属的峨眉角蟾,系贵州省两栖动物分布新记录种。  相似文献   

20.
2006年7月18日~8月14日,由四川大学、中科院成都生物研究所和台湾国立中山大学组成新疆两栖爬行动物考察队,对南北疆进行了为期近一个月的野外考察。本次考察共采集标本328号,经鉴定共23种,分隶11属7科,其中两栖纲2科2属4种,爬行纲5科9属19种。本次调查还发现了一些蜥蜴和蛇种的新分布记录。  相似文献   

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