高榕榕果内Eupristina属两种榕小蜂的遗传进化关系

对生长在福州地区的高榕进行长期追踪观察,发现高榕榕果内仅生活着Eupristina altissima和Eupristina sp.榕小蜂,前者为高榕的传粉小蜂,后者无传粉行为,两者雌蜂之间在体色、触角、花粉袋和花粉刷等部位存在细微的差异,而两者雄蜂之间无形态差异。通过克隆福建地区5个样地的高榕榕果内收集到的E. altissima和Eupristina sp.榕小蜂,以及细叶榕的传粉小蜂Eupristina verticillata(外群)的Cytb及COI基因,并进行碱基组成及遗传距离分析,用邻接法构建系统发育树,分析两榕小蜂群体之间的遗传进化关系,结果显示:(1)榕小蜂COI及Cytb序列碱基组成中A+T的含量(Cytb序列中A+T=75.3%,COI序列中A+T=75.5%)显著高于G+C,符合膜翅目昆虫线粒体基因碱基组成特征。(2)对两群体小蜂进行遗传距离分析显示,Cytb序列中E. altissima和Eupristina sp. 群体内各样本之间的平均遗传距离分别为0.0092和0.0030,而E. altissima与Eupristina sp. 群体间的平均距离为0.1588;COI序列中E. altissima 与Eupristina sp. 群体内各样本之间的平均遗传距离分别为0.0065和0.0205,而二者群体间的平均遗传距离为0.1043,表明两者群体间的遗传距离明显大于各自群体内各样本间的遗传距离。统计GenBank中下载的6个属34种榕小蜂Cytb序列的种间遗传距离为0.0811-0.1723,6个属28种榕小蜂COI序列的种间遗传距离为0.0939-0.1986。由此认为E. altissima和Eupristina sp.之间的遗传距离差异已经达到了种间水平,即E. altissima与Eupristina sp.为两个不同的种。(3)在形态上,两种小蜂的雌蜂之间有微小差异,而二者雄蜂之间无差异,但Cytb与COI序列分析结果一致表明:E. altissima与Eupristina sp.雄蜂之间,以及二者雌蜂之间的遗传距离均差异显著,表明形态变异滞后于基因变异。雌蜂在表型上进化快于雄蜂,可能是由于雌蜂羽化后从榕果出飞,受到外界环境因素的影响较大,且两种雌蜂在传粉功能上存在差异,故二者之间的形态差异较大,而雄蜂寿命短,又终生生活在黑暗封闭、环境变化相对恒定的榕果内,两种雄蜂在行为上不存在差异,故二者表型变异较为缓慢。E. altissima和Eupristina sp.小蜂对宿主的专一性不强,在榕-蜂协同进化过程中,可能发生过宿主转移事件。     

DNA barcoding for the identification of eight species members of the Thai Hyrcanus Group and investigation of their stenogamous behavior

Eight species members of the Thai Hyrcanus Group were identified based on the intact morphology and molecular analysis (COI barcoding, 658 bp) of F₁-progenies. Five iso-female lines of each species were pooled in order to establish stock colonies. A stenogamous colony of each species was investigated by making 200 and 300 newly emerged adult females and males co-habit in a 30 cm cubic cage for one week. After ovipositon, the spermathecae of females were examined for sperms. The results revealed that Anopheles argyropus, Anopheles crawfordi, Anopheles nitidus, Anopheles pursati, Anopheles sinensis, Anopheles nigerrimus, Anopheles paraliae and Anopheles peditaeniatus yielded insemination rates of 0%, 0%, 0%, 31%, 33%, 42%, 50% and 77%, respectively. Continuous selection to establish stenogamous colonies indicated that An. sinensis, An. pursati, An. nigerrimus, An. paraliae and An. peditaeniatus provided insemination rates of 33–34%, 27–31%, 42–58%, 43–57% and 61–86% in 1, 2, 5, 6 and 20 generations of passages, respectively.     

Volatile and molecular analysis of Juniperus brevifolia (Seub.) Antoine,an Azorean endemic species

Chemical and molecular analyses were performed for the characterization of Juniperus brevifolia (Seub.) Antoine (Cupressaceae), an Azorean endemic species. Forty-two individual twig samples were collected at seven Azorean islands (S. Miguel, Terceira, S. Jorge, Pico, Faial, Flores and Corvo). Volatile compounds were isolated by distillation–extraction and analyzed by GC and GC-MS. The volatile oils consisted mainly of monoterpene hydrocarbons (84–96%), limonene (33–87%), α-pinene (1–48%) and β-myrcene (1–5%) being the main components, and cluster analysis showed a high correlation among all samples (S_corr = 0.84). DNA fingerprinting was performed using thirty-seven RAPD and eleven ISSR primers, generating 881 polymorphic bands. Cluster analysis showed a moderate correlation among accessions (S_Dice = 0.43), which grouped according to their geographical origin. Chemical and molecular data did not show superimposable clustering profiles. Although the molecular approaches tested were useful in assessing genetic diversity, no straight correlation could be drawn between chemical and molecular data sets.     

Two new species in the Echinoderes coulli group (Echinoderidae,Cyclorhagida, Kinorhyncha) from the Ryukyu Islands,Japan

Two new species belonging to the Echinoderes coulli group are described with their external morphologies and sequences of nuclear 18S rRNA and 28S rRNA genes, and mitochondrial COI gene. The first species, Echinoderes komatsui sp. n., is characterized by absence of acicular spines, and presence of lateroventral tubules on segments 5 and 8, laterodorsal tubules on segment 10, inverted triangle or wide oval shaped large sieve plates, lateral terminal accessory spines in female, and short tips of ventral pectinate fringe on segment 10. The second species, Echinoderes hwiizaa sp. n., is characterized by absence of acicular spines, and presence of lateroventral tubules on segments 5 and 7–9, midlateral tubules on segment 8, laterodorsal tubules on segment 10, large narrow oval shaped sieve plates on segment 9, and thick, short and blunt lateral terminal spines about 10–15% of trunk length. The diagnostic characters and key to species of E. coulli group are provided as well.     

Description and DNA barcoding of Crematogaster fraxatrix Forel, 1911 and two new closely related species from Cambodia and Indonesia (Hymenoptera,Formicidae)

Crematogaster fraxatrix Forel, 1911 and two new species, C. chhangi sp. n. and C. simboloni sp. n., are described from Cambodia and Indonesia, respectively. DNA sequences were generated for C. fraxarix and the two newly described species using 3 amplications of two regions of the mitochondrial gene COI with a total of 1129 bp. The mean interspecific divergences are 9.4% and 23.5% for C. fraxatrix vs. C. chhangi, C. simboloni, respectively. DNA sequences reveal that C. simboloni is found to be genetically distinct from the other two species, but C. chhangi is not distinct from C. fraxatrix.     

The Praon dorsale–yomenae s.str. complex (Hymenoptera,Braconidae, Aphidiinae): Species discrimination using geometric morphometrics and molecular markers with description of a new species

In this paper we apply an integrative approach combining morphometric and molecular analyses to explore parasitoids of the Praon dorsale–yomenae s.str. complex. These parasitoids occur in natural and agricultural ecosystems throughout the Palaearctic and parasitize aphid hosts belonging to the tribe Macrosiphini. The P. dorsale–yomenae species complex represents a morphologically cryptic group, consisting of several hidden taxa with specific host adaptations and distributions. For the morphometric analyses we used a large dataset comprising 230 female specimens that emerged from 30 different species of aphid hosts throughout the Palaearctic. The molecular analysis included a reduced dataset of 44 specimens that emerged from 19 aphid hosts. The mitochondrial cytochrome oxidase subunit I (COI) and the nuclear second expansion segment of the 28S rRNA gene (28SD2) were used to estimate a genetic diversity within this complex. Although all Praon species clustered closely together in the 28SD2 tree, confirming their close relatedness, the molecular characterization based on COI identified five clearly separate taxa with sequence divergences in the range of 4.7–8.9%. These taxa also exhibited significant differences in forewing shape as revealed by geometric morphometric analyses. Classical morphometric analyses revealed the length of m-cu vein as a new taxonomic character, but suggested that one commonly used trait, the color pattern of the Rs + M and m-cu veins, cannot be used for species distinction as it was highly variable in one of the taxa. Based on the combined morphometric and genetic data, we confirm the species status of Praon dorsale, P. yomenae, P. longicorne and P. volucre, and describe and illustrate a new parasitoid species of the “dorsale–yomenae” group, i.e. Praon staticobii n.sp. associated with Staticobium limonii on Limonium angustifolium.     

A new species of Docosia Winnertz from Central Europe,with DNA barcoding based on four gene markers (Diptera,Mycetophilidae)

A new species of Docosia Winnertz, Docosia dentata sp. n., is described and illustrated, based on a single male specimen collected in Muránska planina National Park in Central Slovakia. DNA sequences (COI, COII, CytB, and ITS2) are included and compared for 13 species of Docosia. There was found only little congruence between the molecular results and previous scarce data about interspecific relationships based on morphology. The COI and CytB gene markers showed the highest interspecific gene distances while ITS2 showed the lowest ones. An updated key to the 23 Central European species of Docosia is also presented.     

Molecular phylogeny and biogeography of the narrow endemic Coelonema and affinitive Draba (Brassicaceae) based on two DNA regions

To clarify the relationship between two genera, Draba and the narrow genus Coelonema, endemic to the QilianMountains of the northeastern Qinghai-Tibet Plateau, phylogenetic analyses were conducted using nuclear ribosomal DNA ITS, and the chloroplast DNA trnL, from Coelonema draboides and 30 species of Draba representing eight sections, including 25 species of Chinese Draba, seven of which were endemic to the study region. The results unambiguously support several previously published proposals to unite Coelonema with Draba and accommodate C. draboides in the latter genus on the basis of morphological re-examination. Our molecular data presented here also provide evidence that these two genera should be combined as a monophyletic group with high support. In addition, it is estimated that Draba may have originated about 1.36–2.71 Mya, with C. draboides diverging from Draba about 0.15–0.31 Mya, based on the molecular calibration of ITS datasets. The assumed speciation and rapid expansion of these two genera is likely to have occurred in the eastern edge of the QilianMountains area according to molecular phylogeny and estimated divergence times, which correspond well with the known geological and paleobotanical histories of the Qinghai-Tibet Plateau.     

DNA barcodes identify Central Asian Colias butterflies (Lepidoptera,Pieridae)

A majority of the known Colias species (Lepidoptera: Pieridae, Coliadinae) occur in the mountainous regions of Central-Asia, vast areas that are hard to access, rendering the knowledge of many species limited due to the lack of extensive sampling. Two gene regions, the mitochondrial COI ‘barcode’ region and the nuclear ribosomal protein RpS2 gene region were used for exploring the utility of these DNA markers for species identification. A comprehensive sampling of COI barcodes for Central Asian Colias butterflies showed that the barcodes facilitated identification of most of the included species. Phylogenetic reconstruction based on parsimony and Neighbour-Joining recovered most species as monophyletic entities. For the RpS2 gene region species-specific sequences were registered for some of the included Colias spp. Nevertheless, this gene region was not deemed useful as additional molecular ‘barcode’. A parsimony analysis of the combined COI and RpS2 data did not support the current subgeneric classification based on morphological characteristics.     

Secondary metabolites from Eurotium species, Aspergillus calidoustus and A. insuetus common in Canadian homes with a review of their chemistry and biological activities

As part of studies of metabolites from fungi common in the built environment in Canadian homes, we investigated metabolites from strains of three Eurotium species, namely E. herbariorum, E. amstelodami, and E. rubrum as well as a number of isolates provisionally identified as Aspergillus ustus. The latter have been recently assigned as the new species A. insuetus and A. calidoustus. E. amstelodami produced neoechinulin A and neoechinulin B, epiheveadride, flavoglaucin, auroglaucin, and isotetrahydroauroglaucin as major metabolites. Minor metabolites included echinulin, preechinulin and neoechinulin E. E. rubrum produced all of these metabolites, but epiheveadride was detected as a minor metabolite. E. herbariorum produced cladosporin as a major metabolite, in addition to those found in E. amstelodami. This species also produced questin and neoechinulin E as minor metabolites. This is the first report of epiheveadride occurring as a natural product, and the first nonadride isolated from Eurotium species. Unlike strains from mainly infection-related samples, largely from Europe, neither ophiobolins G and H nor austins were detected in the Canadian strains of A. insuetus and A. calidoustus tested, all of which had been reported from the latter species. TMC-120 A, B, C and a sesquiterpene drimane are reported with certainty for the first time from indoor isolates, as well as two novel related methyl isoquinoline alkaloids.     

Species-specificity of oospore dimensions in three ecorticate species of Chara (Charales,Charophyceae)

Dimensions of oospores such as length, width, fossa-breadth, length-to-width ratio and number of striae were considered for morphological identification of the members of Charales. Oospores were collected from natural stands of three species, viz. Chara braunii, C. corallina and C. wallichii in ponds in West Bengal (India). Oospore dimensions (length, width and fossa-breadth) correlated well: though the fossa breadth–length relation of C. braunii showed lower correlation coefficient (r² = 0.076, p < 0.001), all other five breadth or width–length relationships showed r² ≥ 0.23, p < 0.001. These bivariate patterns were significantly different among the species (one-way ANCOVA of length–width ratio to fossa-breadth: adjusted means and slopes both p < 0.001), C. braunii and C. corallina has similar length to width ratios, C. wallichii and C. corallina were similar in width, whereas the species differed in breadth and length in the order C. braunii, C. wallichii, and C. corallina.     

Molecular detection and phylogenetic analysis of the alkane 1-monooxygenase gene from Gordonia spp.

The alkB gene encodes for alkane 1-monooxygenase, which is a key enzyme responsible for the initial oxidation of inactivated alkanes. This functional gene can be used as a marker to assess the catabolic potential of bacteria in bioremediation. In the present study, a pair of primers was designed based on the conserved regions of the AlkB amino acid sequences of Actinobacteria, for amplifying the alkB gene from the genus Gordonia (20 Gordonia strains representing 13 species). The amplified alkB genes were then sequenced and analyzed. In the phylogenetic tree based on the translated AlkB amino acid sequences, all the Gordonia segregated clearly from other closely related genera. The sequence identity of the alkB gene in Gordonia ranged from 58.8% to 99.1%, which showed higher sequence variation at the inter-species level compared with other molecular markers, such as the 16S rRNA gene (93.1–99.8%), gyrB gene (77.5–97.3%) or catA gene (72.4–99.5%). The genetic diversity of four selected loci also showed that the alkB gene might have evolved faster than rrn operons, as well as the gyrB or catA genes, in Gordonia. All the available actinobacterial alkB gene sequences derived from the whole genome shotgun sequencing projects are phylogenetically characterized here for the first time, and they exclude the possibility of horizontal gene transfer of the alkB gene in these bacterial groups.     

Evolutionary history of frogfishes (Teleostei: Lophiiformes: Antennariidae): a molecular approach

Fishes of the family Antennariidae (order Lophiiformes) are primarily shallow-water benthic forms found in nearly all tropical and subtropical oceans and seas of the world, with some taxa extending into temperate waters. Despite an earlier attempt based on morphology, no previous hypothesis of intergeneric relationships of the Antennariidae exists. To resolve phylogenetic relationships within the Antennariidae, and to test the validity of species groups within Antennarius, DNA sequences from the mitochondrial 16S and cytochrome oxidase c subunit 1 (COI) genes, and nuclear recombination activating gene 2 (RAG2), for 25 described and four undescribed antennariid species, representing 10 of 12 known genera and one undescribed genus, were unambiguously aligned and analyzed using Bayesian and maximum likelihood methods. The markers were partitioned and analyzed for substitution saturation and only the third codon position of COI (COI-3) was found to have reached saturation. However, analysis of both datasets, one with the saturated data and one without, differed only slightly. All molecular analyses recovered two major clades, one comprised of Fowlerichthys, Antennarius, Histrio, and Antennatus; and another containing Rhycherus, Antennariidae gen. et sp. nov., Kuiterichthys, Phyllophryne, Echinophryne, Tathicarpus, Lophiocharon, and Histiophryne. Evidence is presented to illustrate a correlation between phylogeny, geographic distribution, and reproductive life history. The results of these analyses provide the first hypothesis of evolutionary relationships within the Antennariidae.     

Meiothermus rufus sp. nov., a new slightly thermophilic red-pigmented species and emended description of the genus Meiothermus

Four red-pigmented isolates, with optimum growth temperatures of approximately 55–60 °C and an optimum pH for growth between 7.5 and 8.5, were recovered from hot springs in Central France. Phylogenetic analysis of the 16S rRNA gene sequences showed that these organisms represented a new species of the genus Meiothermus. The new isolates could be distinguished from other strains of the species of the genus Meiothermus primarily by the glycolipid profile and fatty acid composition because these organisms lacked the hydroxy fatty acids and the glycolipid variant GL-1a found in all other isolates of the species of Meiothermus examined. On the basis of the results presented here we propose the name Meiothermus rufus for the new species, which is represented by strains CAL-4^T (=DSM 22234^T=LMG 24878^T) and CAL-12 (=DSM 22235=LMG 24879). We also propose emending the genus Meiothermus to include strains that have only one glycolipid instead of two glycolipid variants.     

Morphometric analysis of six Gerbillus species (Rodentia,Gerbillinae) from Tunisia

Size and shape changes in the skull of the genus Gerbillus were investigated using geometric morphometrics. Six species from Tunisia were studied (G. gerbillus, G. campestris, G. nanus, G. tarabuli, G. simoni and G. latastei). Statistical analyses of shape variability allowed us to discriminate three morphological groups which are congruent with the three groups suggested by previous morphological and molecular studies. However, our results contrast with previous molecular investigations. In fact, according to results obtained by the use of principal component analysis, canonical variate analysis and UPGMA, we found a higher degree of divergence between the subgenus Dipodillus and the other two subgenera Gerbillus and Hendecapleura. This fact suggests that the morphometric differences observed among species within the genus Gerbillus are not mainly related to phylogeny. To reconciliate the molecular and morphological approaches, we propose a hypothesis of differential rates of phenotypic evolution in the genus Gerbillus. In this view, the species belonging to the subgenus Dipodillus evolved apomorphic features of the skull likely related to a higher degree of habitat specialization. By contrast, the more generalist Gerbillus and Hendecapleura subgenera show less differentiated plesiomorphic morphology.     

A new species of shrimp of the genus Anachlorocurtis Hayashi, 1975 from the Red Sea,with range extension of A. commensalis Hayashi, 1975 (Crustacea,Decapoda, Pandalidae)

A new species of pandalid shrimp Anachlorocurtis occidentalis sp. n., associated with antipatharian corals, is described and illustrated from the north-eastern Red Sea. This new species is closely related to Anachlorocurtis commensalis Hayashi, 1975, the only other species in the genus, and can be distinguished by the more slender body and appendages; the carapace with 3 large, and one small, subtriangular lobes in the middorsal line; a flattened dorsal outline of the third abdominal segment; the sixth abdominal segment twice as long as fifth one; propodi of the ambulatory pereiopods bearing only a single posterior spinule; and harbouring 3–5 pairs of dorsolateral spines on the telson. A revised generic diagnosis is provided here to accommodate the present new species. The genetic divergence of mitochondrial gene cytochrome c oxidase subunit I (COI) between Anachlorocurtis occidentalis sp. n., and A. commensalis is 15.2–15.4%. Molecular analysis also confirmed a sister position of the genus Anachlorocurtis to Miropandalus. The present records of A. commensalis from Taiwan constitute an extension of the known range of the species.     

Predicting the contributions of novel marine prey resources from angling and anadromy to the diet of a freshwater apex predator

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Composition of epicuticular wax layer of two species of Mandevilla (Apocynoideae,Apocynaceae) from Rio de Janeiro,Brazil

The chemical composition of epicuticular waxes of Mandevilla guanabarica and Mandevilla moricandiana was comparatively analyzed by extraction in n-hexane and chloroform. The mean wax content per unit of leaf area in the n-hexane extract was about 13–30 μg cm⁻² for M. guanabarica, containing 20–28% n-alkanes and 55–63% triterpenes; for M. mori-candiana, the mean content was 19 μg cm⁻², containing 73% n-alkanes and 14% triterpenes. In the chloroform extract, the wax yield was 40–80 μg cm⁻² for M. guanabarica, with about 9–11% n-alkanes and 75–82% triterpenes; while for M. moricandiana, the wax yield was 110 μg cm⁻², with 52% n-alkanes and 14% triterpenes. The major compounds identified were lupeol, pentacyclic triterpenes of the α- and β-amyrin class, and n-alkanes such as nonacosane, hentriacontane and tritriacontane. These results indicate that the quantitative chemical profiles of epicuticular waxes of M. guanabarica and M. moricandiana are distinct and could be used as an additional feature in taxonomic identification.     

Zoanthids (Cnidaria: Hexacorallia: Zoantharia) from shallow waters of the southern Chilean fjord region, with descriptions of a new genus and two new species

The taxonomy of the order Zoantharia (=Zoanthidea=Zoanthiniaria) is greatly hampered by the paucity of diagnostic morphological features. To facilitate discrimination between similar zoanthids, a combination of morphological and molecular analyses is applied here. The three most abundant zoanthid species in shallow waters of the southern Chilean fjord region are described. Comparison with other zoanthids using molecular markers reveals that two of them are new to science; these are described as Mesozoanthus fossii gen. n., sp. n. and Epizoanthus fiordicus sp. n. Their representatives grow on rocky substratum and do not live in symbiosis with demosponges. In the less abundant M. fossii, animals are greyish in colour and resemble members of Parazoanthus in growth form. Individual polyps can be up to 35 mm long. The more abundant E. fiordicus are also greyish; the polyps arise from thin stolons and reach only 12 mm in length. The third species studied is Parazoanthus elongatus McMurrich, 1904. For these three Chilean zoanthid species, in-situ photographs are presented as well as information on distribution, habitat and associated species. Establishment of the Mesozoanthus gen. n. is of particular importance to taxonomy in the chaotic suborder Macrocnemina.