从细胞色素b基因序列探讨我国林蛙属动物的系统发生关系

对中国林蛙属动物进行了DNA水平的分子系统发生研究,测定了中国林蛙属7种15个样品,侧褶蛙属2种2个样品Cyt b基因长约360bp片段的序列。对这些序列的系统发生分析表明：（1）中国林蛙甘肃种群与东北种群序列差异较大,但尚难根据序列差异来判断它们是不同的亚种还是不同的物种;（2）7种林蛙中,中国林蛙与黑龙江林蛙的亲缘关系最近,与桓仁林蛙最远;（3）支持将昭觉林蛙,镇海林蛙,峨眉林蛙和长肢林蛙归入日本林蛙种组Rana japonica group。     

Evaluation of Developmental Stability and Cytogenetic Homeostasis in Populations of European Green Frogs (Rana esculenta-Complex) under Natural and Anthropogenic Conditions

The status of amphibians in populations subjected to anthropogenic influence of various natures has been evaluated. We studied the effect of complex anthropogenic influences as well as chemical and radiation pollution. The status of the specimens in populations was evaluated by morphological (developmental stability as the level of fluctuating asymmetry) and cytogenetic (micronucleus test) methods. Disturbed developmental stability and cytogenetic homeostasis have been observed in populations affected by anthropogenic factors, which indicates the changed status of the organism.     

High Prevalence of Batrachochytrium dendrobatidis in Wild Populations of Lowland Leopard Frogs Rana yavapaiensis in Arizona

Batrachochytrium dendrobatidis (Bd) is a fungus that can potentially lead to chytridiomycosis, an amphibian disease implicated in die-offs and population declines in many regions of the world. Winter field surveys in the last decade have documented die-offs in populations of the lowland leopard frog Rana yavapaiensis with chytridiomycosis. To test whether the fungus persists in host populations between episodes of observed host mortality, we quantified field-based Bd infection rates during nonwinter months. We used PCR to sample for the presence of Bd in live individuals from nine seemingly healthy populations of the lowland leopard frog as well as four of the American bullfrog R. catesbeiana (a putative vector for Bd) from Arizona. We found Bd in 10 of 13 sampled populations. The overall prevalence of Bd was 43% in lowland leopard frogs and 18% in American bullfrogs. Our results suggest that Bd is widespread in Arizona during nonwinter months and may become virulent only in winter in conjunction with other cofactors, or is now benign in these species. The absence of Bd from two populations associated with thermal springs (water >30°C), despite its presence in nearby ambient waters, suggests that these microhabitats represent refugia from Bd and chytridiomycosis.     

Natural Stressors and Ranavirus Susceptibility in Larval Wood Frogs (Rana sylvatica)

Chronic exposure to stressors has been shown to suppress immune function in vertebrates, making them more susceptible to pathogens. It is less clear, however, whether many natural stressors are immunosuppressive. Moreover, whether stressors make disease more likely or more severe in populations is unclear because animals respond to stressors both behaviorally and physiologically. We tested whether chronic exposure to three natural stressors of wood frog tadpoles—high-densities, predator-cues, and low-food conditions—influence their susceptibility to a lethal ranavirus both individually in laboratory experiments, and collectively in outdoor mesocosms. Prior to virus exposure, we observed elevated corticosterone only in low-food treatments, although other treatments altered rates of growth and development as well as tadpole behavior. None of the treatments, however, increased susceptibility to ranavirus as measured by the proportion of tadpoles that became infected or died, or the time to death compared to controls. In fact, mortality in the mesocosms was actually lower in the high-density treatment even though most individuals became infected, largely because of increased rates of metamorphosis. Overall we find no support for the hypothesis that chronic exposure to common, ecologically relevant challenges necessarily elevates corticosterone levels in a population or leads to more severe ranaviral disease or epidemics. Conditions may, however, conspire to make ranavirus infection more common in metamorphosing amphibians.     

宁波地区黑斑蛙的繁殖生态和产卵地选择

黑斑蛙是我国分布最广的两栖动物之一,但目前有关其繁殖生态和产卵地选择还所知甚少,而且多局限于定性描述。2004—2006年在宁波地区黑斑蛙的繁殖期,对黑斑蛙的繁殖生态研究分析表明,该蛙在繁殖期的种群密度为0.0903±0.0029只/m(n=11);该蛙是雌雄二形性的蛙类,雌性蛙类的体重和体长都显著大于雄性;该蛙窝卵数的变化幅度较大(1546—7897个),平均窝卵数为4643.04±235.96个(n=50);卵径范围为1.50—1.74mm,平均卵径大小为1.6050±0.0046mm(n=226)。对黑斑蛙产卵地选择的研究结果表明,产卵地在水域比率、裸地比率、植被盖度、水深、水温和水的透明度等方面与随机样方不同;该蛙偏爱在水域比率和植被盖度较高的生境产卵,而避免在水体较深的生境产卵。为了更好地保护黑斑蛙的产卵栖息地,今后应优先保护水域比率和植被盖度较高而水体不深的生境。     

贵州发现寒露林蛙

2016年5月,在贵州雷公山国家级自然保护区南刀村(26°21′N,108°20′E,海拔1 400 m)采集到2只林蛙标本,经鉴定为寒露林蛙(Rana hanluica),为贵州省两栖动物新纪录。     

内蒙古扎兰屯地区发现中国林蛙（无尾目：蛙科）

2016年4月,采集内蒙古呼伦贝尔市扎兰屯地区的林蛙,经形态学(形态描述、体型大小)和分子生物学鉴定,确定该物种为中国林蛙(Rana chensinensis)。研究结果重新证实了中国林蛙在内蒙古呼伦贝尔地区的分布,扩展了对中国林蛙分布范围的认识。     

寒露林蛙的核型和Ag-NORs研究

采用常规骨髓细胞制片法对产于湖南省双牌县的寒露林蛙的核型及NORs位点进行了观察和分析.结果表明寒露林蛙与分布于我国南方的其他林蛙相同:2n=26,NF=52,为5+8核型模式.寒露林蛙核型为14M+10SM+2ST,无次溢痕,NORs位于第11对染色体长臂的中部.通过比较分析我国2n=26的6种林蛙的核型等细胞遗传学信息,本文结果支持形态分类和分子系统发生的研究结论,认为寒露林蛙是一有效种.     

Identification and Functional Analysis of Novel Bradykinin-Related Peptides (BRPs) from Skin Secretions of Five Asian Frogs

In recent decades, various types of bioactive substances have been identified from amphibian skin and its secretions. Bradykinin-related peptides (BRPs) are among these compounds that make up the host defence system of amphibians. In the present study, we identified six novel BRPs, amolopkinin-GN1, amolopkinin-RK1, amolopkinin-TR1, amolopkinin-LF1, ranakinin-MS1, and ranakinin-MS2, from five East Asian amphibians, Amolops granulosus, Amolops ricketti, Amolops torrentis, Amolops lifanensis, and Hylarana maosonensis. This is the first report on BRPs in the skin of these species. Physiological assays reveal that these peptides have a contractive effect on the smooth muscle of rat ileum.     

Widespread Occurrence of the Chytrid Fungus Batrachochytrium dendrobatidis on Oregon Spotted Frogs (Rana pretiosa)

The pathogen Batrachochytrium dendrobatidis (Bd) has been associated with amphibian declines in multiple continents, including western North America. We investigated Bd prevalence in Oregon spotted frog (Rana pretiosa), a species that has declined across its range in the Pacific Northwest. Polymerase chain reaction analysis of skin swabs indicated that Bd was prevalent within populations (420 of 617 juvenile and adults) and widespread among populations (36 of 36 sites) where we sampled R. pretiosa in Oregon and Washington. We rarely detected Bd in R. pretiosa larvae (2 of 72). Prevalence of Bd in postmetamorphic R. pretiosa was inversely related to frog size. We found support for an interactive effect of elevation and sampling date on Bd: prevalence of Bd generally increased with date, but this effect was more pronounced at lower elevations. We also found evidence that the body condition of juvenile R. pretiosa with Bd decreased after their first winter. Our data indicate that some Oregon spotted frog populations are currently persisting with relatively high Bd prevalence, but the risk posed by Bd is unknown.     

伞形科3个种5个居群的核型分析

对伞形科前胡属(PeucedanumL.)2个种以及羌活属(NotopterygiumH.Boiss.)1个种3个居群的染色体数目和核型进行了研究。研究表明,它们的染色体数目均为2n=22,核型公式可分别表示为长前胡:2n=2x=22=22 m(1 SAT),属1A型;松潘前胡:2n=2x=22=20 m 2 sm,属2A型;宽叶羌活的3个居群分别是:马边大风顶居群1为2n=2x=22=6 m 12 sm 4 st,属2A型;马边大风顶居群2为2n=2x=22=12 m 4 sm 6 st,属2B型;屏山老君山居群为2n=2x=22=4 m 14 sm 4 st,属2A型。其中长前胡和松潘前胡的染色体数目和核型为首次报道。     

Allozyme Variation among Populations of Rana pirica (Amphibia: Anura)

Genetic variation of Rana pirica , an east Asian brown frog of the R. temporaria group, was elucidated by analysing 140 specimens from 11 populations from Hokkaido and Sakhalin, both locating near the eastern coasts of the Asian continent, and 12 specimens of R. ornativentris from Honshu, Japan mainland, as an outgroup, through horizontal starch gel electrophoresis. Rana pirica shows relatively low genetic differentiation, and high genetic affinities are found between Hokkaido and Sakhalin populations. Populations from these islands are morphologically somewhat differentiated but should be regarded as conspecific. Degree of genetic divergence among populations of amphibian species from Hokkaido, including R. pirica , is not so extensive as that reported for species from Japan mainland and relatively recent formation of amphibian fauna in Hokkaido is suggested.     

High Altitude Frogs (Rana kukonoris) Adopt a Diversified Bethedging Strategy in the Face of Environmental Unpredictability

Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environments, but empirical field evidence from Asia is scarce. Here we tested this hypothesis by exploring spatial patterns in egg size along an altitudinal gradient in a frog species(Rana kukunoris) inhabiting the Tibetan Plateau. Within-clutch variability in egg size increased as the environment became variable(e.g., lower mean monthly temperature and mean monthly rainfall at higher altitudes), and populations in environments with more unpredictable rainfall produced eggs that were smaller and more variable in size. We provide support for a diversified bet-hedging strategy in high-altitude environments, which experience dynamic weather patterns and therefore are of unpredictable environmental quality. This strategy may be an adaptive response to lower environmental quality and higher unpredictable environmental variance. Such a strategy should increase the likelihood of breeding success and maximize maternal lifetime fitness by producing offspring that are adapted to current environmental conditions. We speculate that in high-altitude environments prone to physical disturbance, breeding females are unable to consistently produce the optimal egg size due to physiological constraints imposed by environmental conditions(e.g., duration of the active season, food availability). Species and populations whose breeding strategies are adapted to cope with uncertain environmental conditions by adjusting offspring size and therefore quality show a remarkable degree of ability to cope with future climatic changes.     

Genetic Structure of Brown Trout (Salmo trutta) Populations from Turkey Based on Microsatellite Data

This present study investigated micro- and macro-geographic microsatellite DNA variations using five polymorphic microsatellite loci from 27 brown trout populations in Turkey. Average number of alleles and average observed heterozygosity were 7.4 and 0.254, respectively. Even populations from the same sea basin and river system (the so called micro-geographic regions) had unique alleles. Genetic variation among the populations from macro-geographic regions (different sea basins and river systems) was 45.78%. The mtDNA lineages of brown trout that have previously been identified by mtDNA analyses were supported by the analysis of the microsatellite DNA data in general. The Çatak population, which belongs to the Tigris lineage, was clustered together with the Euphrates populations within the Adriatic mtDNA lineage, based on microsatellite data. Both mitochondrial and microsatellite DNA analyses have made it possible to determine a secondary contact between Adriatic and Tigris lineages.     

Distinct specific status of the Korean brown frog, Rana amurensis coreana (Amphibia: Ranidae)

We used morphological and genetic data to assess the taxonomic status of Rana amurensis coreana and R. a. amurensis. Morphological comparisons revealed these two subspecies to be different from each other in size of body, nature of tubercles on dorsal stripe, degree of development in toe webbing, and condition of lateral spots of trunk. They were also different in sequence of mitochondrial 16S rRNA gene, with genetic distance as large as those observed among different species of brown frogs. Therefore, Korean populations previously considered a subspecies of R. amurensis should be regarded as a distinct species (=R. coreana).     

青海海北发现一例淡黄色高原林蛙

<正>高原林蛙（Rana kukunoris）隶属于两栖纲（Amphibia）无尾目（Anura）蛙科（Ranidae）林蛙属,是青藏高原特有的两栖类动物（谢锋等2000）。高原林蛙背部多为灰褐色或棕红色,疣粒色略浅,其周围褐黑色,体侧散有黑色或红色斑,四肢具黑色横纹,雄蛙腹面多为粉红色或黄白色,雌蛙为红棕色,多无斑（费梁等2012）。在青藏高原高海拔、缺氧、强紫外线环境中,为维持个体生存及栖息地适应,高原林蛙皮肤结构产生了一系列特异性变化（米志平等2016,张湑泽等2018）。     

大王马先蒿云南五个居群遗传变异研究

采用随机扩增多态DNA(RAPD)分子标记方法,对大王马先蒿(PedicularisrexL.)分布在云南中甸、丽江、大理、武定和昆明的5个居群(其中中甸居群有3个亚居群)的遗传多样性和遗传结构进行了研究。结果表明,大王马先蒿居群具有较高的遗传多样性,多态位点百分率P、Shannon表型多样性指数I和Nei的基因多样性指数h分别为82.0%、0.361和0.240,遗传多样性水平与居群的地理分布范围相关;大王马先蒿居群间的遗传变异较高,遗传变异主要发生在居群之间,而不是居群内部;居群间遗传分化系数Gst为0.747,遗传分化明显,居群间基因交流较少。居群间的遗传距离与居群间的相对地理距离具有一定的相关性。对云南西北部中甸居群的3个亚居群的遗传多样性分析表明,居群的遗传多样性水平与海拔高度有一定的相关性。居群间遗传变异较高可能是由于大王马先蒿为短命多年生植物,繁育系统为混交型,且自交占较大比例等原因造成的。     

Range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) in northwestern North America

The dynamic geological and climatic history of northwestern North America has made it a focal region for phylogeography. We conducted a range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) across its range in northwestern North America to understand its evolutionary history and the distribution of clades to inform conservation of R. pretiosa and Great Basin R. luteiventris, candidates for listing under the US Endangered Species Act. Mitochondrial DNA sequence data from a segment of the cytochrome b gene were obtained from 308 R. luteiventris and R. pretiosa from 96 sites. Phylogenetic analysis revealed one main R. pretiosa clade and three main R. luteiventris clades, two of which overlapped in southeastern Oregon. The three R. luteiventris clades were separated from each other by high levels of sequence divergence (average of 4.75-4.97%). Two divergent clades were also uncovered within the Great Basin. Low genetic variation in R. pretiosa and the southeastern Oregon clade of R. luteiventris suggests concern about their vulnerability to extinction.