西北太平洋海岸带大弹涂鱼复合体的隐存种与进化历史简

大弹涂鱼Boleophthalmus pectinirostris间断分布于西太平洋海岸带东亚与马来西亚马六甲海峡,但马来西亚种群的分类地位尚存争议。研究使用线粒体ND5基因序列(718 bp)与核位点Rag1基因序列(1395 bp)对西北太平洋海岸带11个地点的45尾大弹涂鱼属鱼类进行系统发育关系重建,结果表明大弹涂鱼包括东亚与马来西亚两个单系群,两者形成姊妹群关系。GMYC分析、*BEAST物种树支持大弹涂鱼东亚谱系和马来西亚谱系是不同种。分子测定年龄分析表明大弹涂鱼东亚谱系与马来西亚谱系之间的分化时间为2.73百万年。因此,西北太平洋海岸带大弹涂鱼是复合体,包括两个物种:东亚种群是大弹涂鱼Boleophthalmus pectinirostris sensu stricto,而马来西亚种群是隐存种Boleophthalmus sp.。大弹涂鱼与隐存种之间的物种分化可能是晚上新世冰期海平面下降产生的地理隔离以及间冰期洋流对基因交流的阻碍两方面相互作用的结果。     

中国东南沿海弹涂鱼科常见鱼类的遗传多样性和DNA条形码

为了探究中国东南沿海海岸线经济开发、海水污染等对该区域生物遗传多样性的潜在影响,本文使用COI基因作为DNA条形码,对从中国东南沿海广东汕头、福建东山、福建云霄、福建泉州、福建霞浦、上海崇明6个地点采集的大弹涂鱼(Boleophthalmus pectinirostris)、弹涂鱼(Periophthalmus modestus)和青弹涂鱼(Scartelaos histophorus)进行种间和种内的遗传学分析。遗传多样性分析显示,青弹涂鱼的核苷酸多样性(0.0018)在3个种中最低;青弹涂鱼广东汕头种群的核苷酸多样性(0.0018)比福建云霄种群低;大弹涂鱼的上海崇明种群核苷酸多样性(0.0021)低于其他5个地理种群。物种水平分析表明,3个物种间分化明显,种间与种内遗传距离有明显差异;不同种的单倍型在系统发育树上聚成3个高度支持的独立分支。种群水平分析显示,大弹涂鱼的6个不同地理种群之间有共享单倍型,地理种群间与地理种群内的遗传距离重叠;各地理种群之间的基因流较频繁(Nm>4);青弹涂鱼的分析情况与大弹涂鱼基本一致。大弹涂鱼和青弹涂鱼的单倍型在系统发育树上均呈现多系或并系分布格局,并未按地理位置分成不同的单系群。本研究表明,应及时加强3种鱼类及其野生种群遗传多样性的保护,且COI基因对种一级的识别明确可靠,而在地理种群水平的识别则比较困难,有待进一步深入研究。     

长江口及其南部邻近地区大弹涂鱼种群遗传结构及种群历史分析

应用随机扩增多态性DNA（RAPD）技术及细胞色素b（Cytｂ）基因序列,分析了长江口及其南部邻近地区大弹涂鱼（Boleophthalmus pecinirostris）群体遗传结构及种群历史,结果显示这一区域大弹涂鱼群体的遗传多样性水平很高。（1）RAPD分析结果：从100个10碱基随机引物中筛选出30个多态性引物,对长江口九段沙湿地、浙江舟山定海、福建霞浦群体各20个体进行RAPD分析,3个群体分别获得236、270、274条带,共301个有效位点。3群体多态位点比例（P）、Nei基因多样性指数（H）、Shannon多样性指数（I）分别在93.02%—96.35%、0.3890—0.4219、0.5618—0.6044。分子方差分析（AMOVA）表明,大弹涂鱼群体间存在显著的遗传分化（Fst= 0.03004-0.03254,P<0.05）,但仅3.2%的遗传变异来自群体间。（2）Cytｂ基因序列分析结果：从采自九段沙、定海、霞浦及浙江慈溪的42尾大弹涂鱼样本中,共获得33个Cytｂ基因单倍型（序列长1 141 bp）。4群体的平均单倍型多样性（h）、核甘酸多样性（π）分别为0.9814、0.0048。4群体间的遗传分化指数Fst为0.00043—0.07814,仅1.93%的变异来自群体间（AMOVA分析）,而基因交流值却达14.50—30.79,群体间K2-P遗传距离为0.0040—0.0056,从而显示大弹涂鱼群体间没有发生明显的地理分化。以Cyt b基因序列构建的NJ树揭示4个群体的个体组成2个谱系,但这2个谱系与地理分布并不相关。中性检验、错配分析和网络亲缘关系分析皆表明大弹涂鱼群体有过种群扩张,扩张时间约在更新世末期的0.057—0.023百万年前。     

基于序列trnL-trnF和ITS的榉属系统发育与地理分布格局的初步分析

榉属(Zelkova)是包含6个种的榆科小属, 呈东亚、西亚和南欧间断分布。该文基于DNA序列trnL-trnF和ITS构建了榉属的分子系统发育树, 大体上把此属分为3个分支, 分别对应东亚、西亚和南欧的种类, 与前人仅依据ITS序列的结果不同。生物地理的扩散和隔离分化分析(DIVA)表明, 榉属的原始祖先分布区可能是欧亚北温带, 包括了东亚、西亚和南欧的某个大的区域。分化过程以隔离分化为主要特征, 即3个分布区域是逐步隔离分化的。由于东亚的物种多样性, 北太平洋有可能是起源中心。榉属的现代分布格局可能主要是由于渐新世发生的古地中海西退、中新世发生的青藏高原大范围隆升, 以及第四纪冰川活动引起的分布区的收缩。     

鳇亚科似鳇属鱼类的物种界定和系统发育关系

逗亚科似逗属鱼类的物种界定保持争议, 系统发育关系尚待解决。研究取样似逗属鱼类所有种, 使用核基因多位点序列重建似逗属鱼类的系统发育关系, 运用分子的物种界定方法并结合形态特征分析厘定我国似逗属鱼类的分类。贝叶斯系统发育树结果表明: 桂林似逗与平江似逗是单系种; 似逗与扁嘴似逗是多系种, 前者包括五个谱系A至E, 后者包括两个谱系A与B。POFAD距离分析和Structurama分析的结果表明似逗和扁嘴似逗的每个谱系是独立遗传种群, BP & P分析结果强烈支持它们是不同种。*Beast物种树结果揭示: 扁嘴似逗谱系B位于似逗属鱼类的基部位置; 似逗谱系A与B是姊妹群关系, 似逗谱系C是扁嘴似逗谱系A的姊妹群, 它们一起与桂林似逗形成姊妹群关系; 似逗谱系D与E是姊妹群关系, 它们一起是平江似逗的姊妹群。结合形态证据, 对我国似逗属鱼类分类厘定如下: 限定严格意义似逗包括似逗谱系A+B; 恢复长吻似逗(Pseudogobio longirostris Mori, 1934)给予似逗谱系C分类名; 似逗谱系D与E是隐存种, 桂林似逗与平江似逗是有效种。     

线粒体细胞色素氧化酶I (mt COI) 序列分析揭示扶桑绵粉蚧复合种存在隐存谱系

过去约20年间扶桑绵粉蚧Phenacoccus solenopsis Tinsley在许多国家造成严重危害。近年来该害虫传入我国, 对农业生产构成严峻威胁。外来入侵物种的快速准确鉴定是科学研究及其管理的基础。本研究对来自海南三亚和陵水地区的扶桑绵粉蚧的线粒体细胞色素氧化酶I （mt COI）测序并与美国佛罗里达州的扶桑绵粉蚧序列进行了比较。系统发育树表明该物种存在两个遗传支系, 即海南支系与佛罗里达支系; 这两个支系的遗传距离约3%。这是利用mt COI分子标记对我国扶桑绵粉蚧的首次分子鉴定. 这些结果提示：（1）扶桑绵粉蚧可能是至少含有两个隐存谱系或姊妹种的复合种; （2）新入侵我国海南三亚和陵水地区的扶桑绵粉蚧是该复合种内的一个隐存谱系或物种, 且海南三亚和陵水种群可能不是来自美国佛罗里达州。扶桑绵粉蚧隐存谱系的发现对于该物种的分子鉴定及其入侵生态学研究具有重要意义。     

螟蛾总科分子系统学研究进展

螟蛾是常见的中、小型蛾类,其分子系统学研究在近十年发展迅速。本文总结了利用分子系统学方法在螟蛾进化与系统发育关系重建、物种鉴定、近缘种的鉴别和隐存种的发现以及谱系动物地理学、种群遗传变异和分化等方面的研究进展。     

东亚第三纪孑遗植物的亲缘地理学:现状与趋势

通过分析比较近年来东亚第三纪孑遗植物的种群遗传学与亲缘地理学的研究结果,总结了它们的谱系地理格局式样,分析了其形成的共同地史或气候成因,并对未来的研究提出了展望。东亚孑遗植物的谱系地理式样主要表现为以下4个方面:(1)中新世中期至晚期的气候变冷变干驱使孑遗植物发生了近期的物种形成,而上新世末以及更新世的气候变化则促进了它们的种内谱系分化、遗传多样性形成以及种群的收缩与扩张,种群的收缩与扩张导致部分类群形成地理谱系"缝合带"。(2)由于不同的植物类群具有不同的生态位需求以及生物学特点,更新世冰期暴露的东海陆桥对中国–日本间断分布的孑遗植物具有不同的"过滤"与"廊道"效应,从而导致其呈现不同的遗传隔离式样。(3)上新世末青藏高原的快速隆升以及上新世末/更新世初东亚季风气候的加强可能是多个亚热带地区分布的孑遗植物沿四川盆地附近发生东西谱系分化的根本原因,也是西北干旱带分布的孑遗植物发生东西谱系分化的驱动因素。(4)自晚中新世以来的全球气候变冷变干驱使部分第三纪孑遗植物在更新世以前就已经从中国大陆或日本本岛迁入台湾,并发生隔离分化,形成了新的物种或地理谱系。总之,历史与当代的地理以及环境共同影响了东亚第三纪孑遗植物的地理分布、遗传多样性、谱系分化以及物种形成。最后,我们强调了目前由单位点的简单分子钟模型的运用造成的研究不足,并对未来的研究提出了展望,即基因组数据和生物地理模型的使用以及群落水平的整合亲缘地理学研究是未来的研究方向。     

鲴亚科分子系统学研究

为探讨鲴亚科(Xenocyprinae)鱼类系统发育关系,研究基于2种线粒体基因和5种核基因序列对鲴亚科各物种的系统发育关系和分化时间进行评估。结果显示:不同方法和数据类型获得了基本一致的拓扑结构。3个属的单系性都得到了很好地支撑;但是,它们之间的进化关系却随着分子标记的不同而改变。这一结果可能是由于早期的基因流或谱系的随机分选所致。此外,银鲴(Xenocypris argentea)、云南鲴(Xenocypris yunnanensis)和黄尾鲴(Xenocypris davidi)之间呈现出嵌套型的谱系关系,暗示它们之间存在基因交流的可能性。基于化石地层年代校正的分子钟估算结果显示,鲴亚科主要类群的分化发生在中新世晚期,约15—12百万年前(Millions of years ago, Ma),这与东亚季风强盛时期的时间相吻合。     

斑节对虾两个野生亲虾种群遗传多样性

采用RAPD和mtDNA 16S rRNA基因序列分析方法对海南和马来西亚斑节对虾(Penaeus monodon)种群进行了遗传多样性和遗传分化研究.结果表明:15个RAPD随机引物共检测到82个位点,海南和马来西亚种群的多态位点比例分别为75.90％和76.83％,杂合度分别为0.199和0.218,遗传多样性指数分别为0.276和0.288,种群间的遗传距离为0.015;16S rRNA基因检测的种内遗传变异较低,马来西亚和海南种群的核苷酸多样性分别为0.011和0,种群之间的遗传距离为0.008;马来西亚种群比海南种群的遗传变异水平要高得多,且海南种群可能起源于马来西亚种群;进行遗传选育时可考虑引进马来西亚亲虾作为奠基群体.     

Molecular Evidence for Multiple Origins of the European Spined Loaches (Teleostei,Cobitidae)

We present a phylogenetic investigation of the Northern Clade, the major monophyletic clade within the freshwater fish family Cobitidae, one of the most prominent families of freshwater fishes found in Asian and European waters. Phylogenetic reconstructions based on the cytochrome b and RAG-1 genes show the genera Microcobitis, Sabanejewia, Koreocobitis and Kichulchoia as monophyletic groups. These reconstructions also show a Cobitis sensu lato and a Misgurnus sensu lato group. The Cobitis sensu lato group includes all species of Cobitis, Iksookimia, Niwaella and Kichulchoia, while the Misgurnus sensu lato group includes Misgurnus, Paramisgurnus and Koreocobitis. Although the monophyly of both the Cobitis sensu lato and Misgurnus sensu lato groups is supported, relationships within the groups are incongruent with current generic definitions. The absence of monophyly of most genera included in the Cobitis sensu lato group (Cobitis, Iksookimia and Niwaella) or their low genetic differentiation (Kichuchoia) supports their consideration as synonyms of Cobitis. Molecular phylogenies indicate that the Asian species of Misgurnus experienced a mitochondrial introgression from a lineage of Cobitis. We also find two nuclear haplotypes in the same Cobitis species from the Adriatic area that, in the absence of morphological differentiation, may indicate molecular introgression. Most lineages within the Northern Clade consist of species found in East Asia. However, some lineages also contain species from Europe and Asia Minor. The phylogenetic relationships presented here are consistent with previous studies suggesting an East Asian origin of the Northern Clade. According to the current distributions and phylogenetic relationships of the Misgurnus sensu lato and Cobitis clade lineages, particularly of M. fossilis and C. melanoleuca, the range expansion of East Asian species into Europe was most likely via Siberia into Northern and Central Europe. Phylogenetic analyses also show that the Cobitis sensu lato group consists of two clear subgroups (I and II), each presenting geographical differences. Subgroup I is distributed exclusively in East Asian drainages with an Eastern European offshoot (C. melanoleuca), whereas Subgroup II includes species widespread throughout Europe (including the Mediterranean), Asia Minor, the Black Sea and the Caucasus, with some lineages related to species restricted to East Asia.     

Genetic relationships and reproductive-isolation mechanisms among the Fejervarya limnocharis complex from Indonesia (Java) and other Asian countries

In order to elucidate the genetic relationships and reproductive-isolation mechanisms among the Fejervarya limnocharis complex from Indonesia and other Asian countries, allozyme analyses and crossing experiments were carried out using 208 individuals from 21 localities in eight Asian countries. The allozyme analyses revealed that 17 enzymes examined were controlled by genes at 27 loci, and that 7.9 phenotypes were produced by 5.2 alleles on average. The two species recognized in F. limnocharis sensu lato from Southeast Asia (i.e., F. limnocharis sensu stricto and F. iskandari) were found to occur sympatrically at three localities (Bogor, Cianjur and Malingping), all on Java, Indonesia. Fejervaya iskandari was dominant at each of these localities and showed substantial geographic genetic variation. Laboratory-produced hybrids between F. limnocharis and F. iskandari from Java became underdeveloped and died at the tadpole stage, suggesting that these species are completely isolated by hybrid inviability. Hybrids between topotypic F. limnocharis and the Malaysian and Japanese conspecific populations developed normally to metamorphosis. Likewise, hybrids between topotypic F. iskandari and the Thailand and Bangladesh conspecific populations also showed normal viability throughout larval development. The present allozyme analyses and crossing experiments strongly suggested the presence of two distinct forms, the large type and the small type, in the F. limnocharis complex from Asia, and further subdivision of the large type into the F. limnocharis assemblage and the F. iskandari assemblage. The small type was found in samples from India, Thailand, Bangladesh and Sri Lanka, and included at least three different species. The sample from Pilok, Thailand, was considered to represent an undescribed species.     

Molecular identification of the exotic slug <Emphasis Type="Italic">Arion subfuscus</Emphasis> sensu stricto (Gastropoda: Pulmonata) in California,with comments on the source location of introduced populations

Arion subfuscus sensu lato (s. l.) refers to a cryptic slug species complex that is native to Europe and which, from there, has been introduced into the northeastern U.S. The species complex was detected in California for the first time in 2005 and recently 12 specimens were collected during statewide surveys. The genital morphology of these specimens suggested that only A. subfuscus sensu stricto (s. s.) was present and partial sequences of mitochondrial 16S rDNA (443 bp) showed that they all belonged to a single haplotype of the mitochondrial lineage, S1 sensu Pinceel et al. (Genetica 125: 155–171, 2005). This result was corroborated by a parallel analysis of a 655 bp COI DNA barcode. The 16S rDNA S1 haplotype (S1-03) of the Californian specimens is hitherto known only from the northeastern U.S. Hence, it is likely that populations may have been introduced to California from the northeastern states, rather than directly from the native area of the S1 haplogroup in Europe.     

Refugia, differentiation and postglacial migration in arctic-alpine Eurasia, exemplified by the mountain avens (Dryas octopetala L.)

Many arctic-alpine organisms have vast present-day ranges across Eurasia, but their history of refugial isolation, differentiation and postglacial expansion is poorly understood. The mountain avens, Dryas octopetala sensu lato, is a long-lived, wind-dispersed, diploid shrub forming one of the most important components of Eurasian tundras and heaths in terms of biomass. We address differentiation and migration history of the species with emphasis on the western and northern Eurasian parts of its distribution area, also including some East Greenlandic and North American populations (partly referred to as the closely related D. integrifolia M. Vahl). We analysed 459 plants from 52 populations for 155 amplified fragment length polymorphisms (AFLP) markers. The Eurasian plants were separated into two main groups, probably reflecting isolation and expansion from two major glacial refugia, situated south and east of the North European ice sheets, respectively. Virtually all of northwestern Europe as well as East Greenland have been colonized by the Southern lineage, whereas northwest Russia, the Tatra Mountains and the arctic archipelago of Svalbard have been colonized by the Eastern lineage. The data indicate a contact zone between the two lineages in northern Scandinavia and possibly in the Tatra Mountains. The two single populations analysed from the Caucasus and Altai Mountains were most closely related to the Eastern lineage but were strongly divergent from the remaining eastern populations, suggesting survival in separate refugia at least during the last glaciation. The North American populations grouped with those from East Greenland, irrespective of their taxonomic affiliation, but this may be caused by independent hybridization with D. integrifolia and therefore not reflect the true relationship between populations from these areas.     

Two species of goby, Boleophthalmus pectinirostris and Scartelaos sp., as the new second intermediate hosts of heterophyid fluke in Korea

A survey was performed in order to determine the infection status of the metacercariae of heterophyid fluke in two goby species, Boleophthalmus pectinirostris and Scartelaos sp., collected from Gangjin-gun, and Shinangun, Sooncheon-shi, Jeollanam-do, Republic of Korea. A total of three metacercariae of Heterophyopsis continua was found in only one B. pectinirostris (10.0%) from Gangjin-gun. Heterophyes nocens metacercariae were detected in 24 B. pectinirostris (96.0%) and 14 Scartelaos sp. (63.6%) from Shinan-gun. Heterophyopsis continua metacercariae were found in 11 B. pectinirostris (44.0%) and 21 Scartelaos sp. (95.5%) from Shinan-gun. Stictodora fuscata metacercariae were detected in 18 B. pectinirostris (72.0%) from Shinan-gun. No metacercariae were detected in 20 B. pectinirostris from Sooncheon-shi. From the above results, this study is the first to prove that B. pectinirostris and Scartelaos sp. serve as the second intermediate hosts of some heterophyid flukes in Korea.     

Whole genome sequence of an unusual Borrelia burgdorferi sensu lato isolate

Human Lyme disease is caused by a number of related Borrelia burgdorferi sensu lato species. We report here the complete genome sequence of Borrelia sp. isolate SV1 from Finland. This isolate is to date the closest known relative of B. burgdorferi sensu stricto, but it is sufficiently genetically distinct from that species that it and its close relatives warrant its candidacy for new-species status. We suggest that this isolate should be named "Borrelia finlandensis."     

Phylogeny of Adeleid Blood Parasites with a Partial Systematic Revision of the Haemogregarine Complex

ABSTRACT. The phylogenetic relationships of taxa representative of blood parasitic adeleids were investigated in a cladistic analysis. Two phylogenetic analyses were performed. Monophyly of species of Haemogregarina (sensu lato) of some marine fishes with species of Haemogregarina (sensu stricto) was not supported in either analysis. A new genus, Desseria n. g., was created to accommodate these species. The historical burden placed on the genus Haemogregarina Danilewsky, 1885 as a repository for poorly known and inadequately described species is partially relieved through taxonomic revisions involving the genera Haemogregarina , and Desseria n. g.     

Loxocorone,a new genus of the family loxosomatidae (Entoprocta: Solitaria), with descriptions of two new Loxomitra (sensu stricto) and a new Loxocorone from Okinawa,the Ryukyu Archipelago,Japan

The type species of Loxomitra Nielsen, 1964, L. kefersteinii (Claparède, 1867), has following characters: A) the buds have a pair of terminal wings at the base of the stalk, and B) the liberated buds crawl on the substratum by attaching the two terminal wings to the substratum and twisting the whole body. By contrast, some other members of the genus have following characters: A') the buds lack the terminal wings but have a foot with foot groove, and B') the liberated buds glide over the substratum using the foot with foot groove. I thus propose to divide Loxomitra (sensu lato) into two genera- Loxomitra (sensu stricto) characterized by A) and B), and Loxocorone gen. nov. by A') and B'). I also describe two new Loxomitra (sensu stricto), L. mizugamaensis sp. nov., and L. tetraorganon sp. nov., and one new Loxocorone, L. allax sp. nov. from the Ryukyu Archipelago, Japan. All of the currently recognized species of the Loxomitra (sensu lato) are reviewed to specify their generic allocations in response to the above change.     

A rapid method for differentiating Saccharomyces sensu stricto strains from other yeast species in an enological environment

During programs for the selection of enological yeasts, several hundred natural isolates are usually screened. The scope of these operations is to isolate strains possessing good fermentative properties without necessarily arriving at a precise species designation: in other words, to detect strains belonging to the Saccharomyces sensu stricto complex. In the present study, a pair of primers, designed within the variable D1/D2 region of the 26S subunit of ribosomal yeast RNA, have been constructed. These generate an amplification fragment of 471 bp that is specific for the seven Saccharomyces sensu stricto species, while no signal was obtained for Saccharomyces sensu lato strains (17 species) or for another 18 selected species commonly found in enological environments. A second pair of primers was also constructed, within the 18S rRNA gene, composed of perfectly conserved sequences common for all 42 yeast species examined, which generate a 900 bp (c.) band for all strains. This was used as a positive experimental control in multiplex PCR analysis using all four primers.     

广义竹叶青蛇属Trimeresurus (sensu lato)的分类和系统学研究进展

广义的竹叶青蛇属于Trimeresurus(sensu lato)包含有40多个物种,广泛分布在南亚和东南亚国家和地区。目前,该类群已经相继被划分为6个属：Trimeresurus(sensu stricto)、Tropidolaemus、Ovophis Protobothrops,Triceratolepidophis,Zhaoermia本文从形态、细胞以及分了系统学等方面对Trimeresurus(sensu lato)的分类和系统学研究进行综述。