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1.
Twenty species of freshwater fishes were collected from Minnesota, Iowa and Michigan and their whole-body carbon, nitrogen and phosphorus contents and the respective C:N:P ratios were determined. Patterns were examined in intra- and interspecific variation, allometry and variation caused by habitat and trophic level in whole fish while controlling for the role of phylogeny. Stoichiometric variation was greater across than within species, C:N:P allometry was species-specific, nutrient content within a species was somewhat habitat-specific and P concentration showed a strong phylogenetic signal. Stoichiometric relationships with allometry and feeding guild were observed but were not significant in an analysis accounting for non-independence of closely related species. Supportive evidence for the hypothesis that the considerable variation in whole fish phosphorus concentrations could be ascribed to differences in bone and scale development, as previously suggested, is shown. Whole fish Ca:P ratios had a nearly constant stoichiometry consistent with the chemical signature of bone. This result combined with a phylogenetic signal for fish P indicated that the great stoichiometric variability among fish taxa in P content was derived almost entirely from skeletal investment.  相似文献   

2.
Pollen grains of 15 taxa of the genus Chelonopsis (14 spp. and 1 variety) from China and Japan and 6 species of the closely related genera Bostrychanthera (1 species) and Gomphostemma (5 species) were examined by light and scanning electron microscopy. Of these, the pollen morphology of 18 taxa was studied for the first time. Pollen grains were found to be tricolpate with polar lengths of 20.8–30.0 μm and equatorial widths of 17.5–27.3 μm. The basic shape of the pollen in most taxa is subprolate or prolate-spheroidal, but spheroidal, subprolate-spheroidal, oblate-spheroidal, and prolate-subprolate grains are also found in some species. The surface is generally reticulate or suprareticulate in Chelonopsis and granulate in Bostrychanthera. In comparison with those of Chelonopsis and Bostrychanthera, the pollen grain surfaces of Gomphostemma are more diverse. In Chelonopsis, pollen is taxonomically useful at the sectional level, and some grains provide enough characters for species delimitation. The potential pollination ecology of cellular hairs on the anthers of Chelonopsis and Bostrychanthera is also briefly discussed.  相似文献   

3.
Menthol is an organic compound with diverse medicinal and commercial applications, and is made either synthetically or through extraction from mint oils. The aim of the present study was to investigate menthol levels in selected menthol-producing species belonging to the Lamiaceae family, and to determine phylogenetic relationships of menthol dehydrogenase gene sequence among these species. Three genus of Lamiaceae, namely Mentha, Salvia, and Micromeria, were selected for phytochemical and phylogenetic analyses. After identification of each species based on menthol dehydrogenase gene in NCBI, BLAST software was used for the sequence alignment. MEGA4 software was used to draw phylogenetic tree for various species. Phytochemical analysis revealed that the highest and lowest amounts of both essential oil and menthol belonged to Mentha spicata and Micromeria hyssopifolia, respectively. The species Mentha spicata and Mentha piperita, which were assigned to one cluster in the dendrogram, contained the highest amounts of essential oil and menthol while Micromeria species, which was in the distinct cluster and placed in the farther evolutionary distance, contained the lowest amount of essential oil and menthol. Phylogenetic and phytochemistry analyses showed that essential oil and menthol contents of menthol-producing species are associated with menthol dehydrogenase gene sequence.  相似文献   

4.
The oleanolic and ursolic acid contents from 88 taxa of Lamiaceae (19 genera, 66 species, 8 subspecies, 9 varieties and 5 hybrids) were investigated using gas chromatography. Both triterpenoid acids were present in all of the investigated taxa, but the plants belonging in the subfamily Nepetoideae produced significantly higher amounts than those in the subfamily Lamioideae. The oleanolic acid content ranged from traces to 1.840% dry weight, and that of ursolic acid from traces to 4.019% dry weight.  相似文献   

5.
With 84 native species, China is a center of distribution of the genus Salvia (Lamiaceae). These species are mainly distributed in Yunnan and Sichuan provinces (southwestern China), notably the Hengduan Mountain region. Traditionally, the Chinese Salvia has been classified into four subgenera, Salvia, Sclarea, Jungia, and Allagospadonopsis. We tested this classification using molecular phylogenetic analysis of 43 species of Salvia from China, six from Japan, and four introduced species. The nuclear ribosomal internal transcribed spacer region and three chloroplast regions (rbcL, matK, and trnH-psbA) were analyzed by maximum parsimony, maximum likelihood, and Bayesian methods. Our results showed that the Chinese (except Salvia deserta) and Japanese Salvia species formed a well-supported clade; S. deserta from Xinjiang grouped with Salvia officinalis of Europe. In addition, all introduced Salvia species in China were relatively distantly related to the native Chinese Salvia. Our results differed from the subgeneric and section classifications in Flora Reipublicae Popularis Sinicae. We suggested that sections Eusphace and Pleiphace should be united in a new subgenus and that sect. Notiosphace should be removed from subg. Sclarea and form a new subgenus. Our data could not distinguish a boundary between subg. Allagospadonopsis and sect. Drymosphace (subg. Sclarea); the latter should be reduced into the former. Further clarification of the phylogenetic relationships within Salvia and between Salvia and related genera will require broader taxonomic sampling and more molecular markers.  相似文献   

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7.
程燕林  梁军  吕全  张星耀 《生态学报》2011,31(11):3197-3207
葡萄座腔菌科(Botryosphaeriaceae)真菌是农业和林业上重要的病原菌、内生真菌或潜在的致病菌,主要引起树木溃疡病。这类真菌种类繁多,寄主范围广,广泛分布于全球,在生态系统中占有重要的地位。本文综述了近年来国内外在葡萄座腔菌科的分子生态学研究方面取得的新进展。简要介绍了葡萄座腔菌科真菌物种鉴定及其研究方法方面的发展,并列出了2006年以来发现的6个新属和38个新种;概述了该科各个种、属之间的系统发育关系以及科内区分的18个群。在真菌种群遗传结构及其与寄主关系方面,已有研究表明葡萄座腔菌科真菌大体可分为寄主专化型和广谱寄生型两种类型,并已经揭示了无性型为Diplodia,Lasiodiplodia和Dothiorella等部分种群的遗传结构及它们与寄主之间的联系。在种内遗传多样性和基因流动研究方面,展示了利用ISSR、SSR等分子标记方法取得的一些重要结果,有些种群(如Lasiodiplodia theobromae)没有寄主专化性,它们在不同寄主间表现出很强的基因流动,但在不同区域内的基因交流却很有限。文章最后讨论了该科分子生态学研究有待进一步解决的问题。  相似文献   

8.
Relationships between the major lineages of snakes are assessed based on a phylogenetic analysis of the most extensive phenotypic data set to date (212 osteological, 48 soft anatomical, and three ecological characters). The marine, limbed Cretaceous snakes Pachyrhachis and Haasiophis emerge as the most primitive snakes: characters proposed to unite them with advanced snakes (macrostomatans) are based on unlikely interpretations of contentious elements or are highly variable within snakes. Other basal snakes include madtsoiids and Dinilysia--both large, presumably non-burrowing forms. The inferred relationships within extant snakes are broadly similar to currently accepted views, with scolecophidians (blindsnakes) being the most basal living forms, followed by anilioids (pipesnakes), booids and booid-like groups, acrochordids (filesnakes), and finally colubroids. Important new conclusions include strong support for the monophyly of large constricting snakes (erycines, boines. pythonines), and moderate support for the non-monophyly of the trophidophiids' (dwarf boas). These phylogenetic results are obtained whether varanoid lizards, or amphisbaenians and dibamids, are assumed to be the nearest relatives (outgroups) of snakes, and whether multistate characters are treated as ordered or unordered. Identification of large marine forms, and large surface-active terrestrial forms, as the most primitive snakes contradicts with the widespread view that snakes arose via minute, burrowing ancestors. Furthermore, these basal fossil snakes all have long flexible jaw elements adapted for ingesting large prey ('macrostomy'), suggesting that large gape was primitive for snakes and secondarily reduced in the most basal living foms (scolecophidians and anilioids) in connection with burrowing. This challenges the widespread view that snake evolution has involved progressive, directional elaboration of the jaw apparatus to feed on larger prey.  相似文献   

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该文首次报道了唇形科5种植物在广西的新记录——簇序属(Craniotome Reichenb.)及簇序草[Craniotome furcata(Link)Kuntze]、西南水苏[Stachys kouyangensis(Vaniot)Dunn]、海南深红鸡脚参[Orthosiphon rubicundus(D.Don)Benth.var.hainanensis Sun ex C.Y.Wu]、黄花香薷[Elsholtzia flava(Benth.)Benth.]、滨海白绒草[Leucas chinensis(Retz.)R.Br.]。引证标本均存放于广西中医药研究院标本馆(GXMI)。  相似文献   

11.
Urbanization is one of the most extensive and ecologically significant changes happening to terrestrial environments, as it strongly affects the distribution of biodiversity. It is well established that native species richness is reduced in urban and suburban areas, but the species traits that predict tolerance to urbanization are yet little understood. In birds, one of the most studied groups in this respect, evidence is appearing that acoustic traits influence urban living, but it remains unknown how this compares to the effects of more obvious ecological traits that facilitate urban living. Therefore, it remains unclear whether acoustic communication is an important predictor of urban tolerance among species. Here, with a comparative study across 140 European and North American passerines, I show that high song frequency, which is less masked by the low‐frequency anthropogenic noise, is associated with urban tolerance, with an effect size over half that of the most important ecological trait studied: off‐ground nesting. Other nesting and foraging traits accepted to facilitate urban living did not differ for species occurring in urban environments. Thus, the contribution of acoustic traits for passerine urban tolerance approximates that of more obvious ecological traits. Nonetheless, effect sizes of the biological predictors of urban tolerance were low and the phylogenetic signal for urban tolerance was null, both of which suggest that factors other than phenotypic traits have major effects on urban tolerance. A simple possibility is exposure to urbanization, as there was a higher proportion of urban‐tolerant species in Europe, which is more urbanized than North America.  相似文献   

12.
A taxonomic treatment ofSalvia sect.Ekmania, a group of tall shrubs endemic to the Caribbean island of Hispaniola, is provided. Morphology, phenology, pollination biology, habitats, and distributions are discussed. Species boundaries are examined using phenetic analysis of morphological data. Eight species are here accepted as belonging to the section. Two recently described species,S. lavendula andS. paryskii, are considered for inclusion in the section, but only the latter appears to be a member.Salvia lachnaiclada andS. ottoschulzii are treated as conspecific.Salvia bahorucona is recognized as a distinct species.  相似文献   

13.
Subtribe Withaniinae (Solanaceae) comprises seven genera and c. 40 species, with an almost cosmopolitan distribution. Athenaea and Aureliana are exclusively South American, with diversity centres in the Brazilian Atlantic Rainforest. The generic status of Athenaea and Aureliana was investigated using molecular phylogenetic analysis of five plastid regions (ndhF gene, trnL intron and trnL‐trnF, psaI‐accD and trnC‐ycf6 intergenic spacers), nuclear internal transcribed spacers (ITS) and morphometric analysis of the calyx. Divergence time estimates were also performed. Withaniinae was recovered as monophyletic. The diversification time estimated for Withaniinae was 6.3 Myr, and the estimated diversification time for the Athenaea and Aureliana clades was 2.3 Myr. Athenaea and Aureliana species formed a strongly supported clade. However, the genera were not monophyletic, and support for internal relationships was moderate to weak. The morphometric analysis of the increasing size of the fruit calyx that included all species of the genera showed a cline that did not allow us to conclude that the species could be separated into two genera. Because the accrescent calyx is the only morphological character that distinguishes them, we recognize Athenaea as a synonym of Aureliana and propose five new combinations. The list of accepted species is presented. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 00 , 000–000.  相似文献   

14.
Summary The innervation pattern of the intermediate lobe of the skate (Raja radiata) was studied with histological and fluorescence histochemical methods. Neurosecretory fibres, stained with i.a. pseudo-iso-cyanine, were found running in bundles in the central parts of the cell cords. They terminated partly around the perinuclear parts of the intermedia cells, partly around the apices of the cells close to the vascular walls.A catecholamine innervation of the intermedia was also established. Catecholaminecontaining fibres with the appearance of nerve terminals were found around the intermedia cell apices close to the vessels. In some specimens, catecholamine fibres also seemed to terminate at the perinuclear parts of the cells.Thus it is possible, judging solely from structural relations, that both the cell body (the synthesis pole) and the cell apex (the release pole) receive a dual innervation. Recent experimental evidence indicates that the release of MSH from the pars intermedia is controlled by catecholamine fibres, but as yet there is only structural evidence for a special control of hormone synthesis.This study was supported by grants from the Swedish Natural Science Research Council (No. 99-35 and 2126-2) and was carried out within a research organization sponsored by the Swedish Medical Research Council (Projects No. B70-14X-712-05 and B70-14X-56-06).  相似文献   

15.
Pericarp structure is investigated in 143 specimens belonging to 59 out of ca. 65 genera and 134 out of ca. 2,000 species of Lamiaceae subfamily Nepetoideae tribe Mentheae. Some of the data presented by earlier authors are believed to be incorrect. The variation in pericarp structure has been found to be strongly correlated to the variations in DNA and gross morphological characters. The groups of two-staminate genera (Salvia, etc.) and four-staminate genera of Salviinae (Lepechinia and Chaunostoma) can be distinguished from each other and from other labiates by differences in pericarp structure. The other two subtribes, Menthinae and Nepetinae, differ considerably, but their variations strongly overlap. The differences in pericarp structure also suggest that Menthinae can be divided into three main monophyletic groups based on other data: (1) the main bulk of the tribe, (2) a group of Prunella and Cleonia and perhaps also Horminum, and (3) the characteristic genus Lycopus. Pericarp data disagree with a suggestion that the genus Melissa should be included in the subtribe Salviinae. Modifications of the subtribal classification of Mentheae are discussed.  相似文献   

16.
17.
The 24 members of the Euro-Asiatic genus Thymogethes are highly specialized pollen beetles associated as larvae with flowers of Lamiaceae Nepetoideae. All members of the genus were analysed in within the framework of an integrative taxonomy approach, which was aimed to reconstruct the phylogenetic relationships, as well as the possible pattern of evolution of their larval-host-plant association. Evidence from multiple molecular markers [COI; 16S; H3], combined with an estimation of divergence times using an average rate of 0.0177 substitutions/site/My among branches, placed the origin of the genus at a minimum of 9–10 Mya. This date of origin approximates the known evolution of the host plants in Euro-Mediterranean areas. Evidence from combined molecular and cladistic morphological analyses resulted in suitable agreement with the previously established morphology-based systematics of the genus, although members of the exilis species-group were split into three clades. The only disagreement between results of this new combined phylogeny and previous classification is in the exclusion of “Thymogethesgrenieri. This species is herein positioned outside the genus, based on molecular evidence. Our analysis depicts several Thymogethes species differentiating in the last few Mys, specifically those included in the T. lugubris species-group. Combined evidence from DNA, morphology and ancestral state parsimony reconstruction of larval-host-plant associations suggests that subtribe Menthinae likely represents the ancestral host plants, with a series of independent host shifts during the radiation of the clade, in association first with Menthinae and subsequently with Lavandulinae and Nepetinae. Steno-oligophagy is the most frequent (86%) condition, while strictly monophagous species are less numerous (14%).  相似文献   

18.
Spider major ampullate silk is a high-performance biomaterial that has received much attention. However, most studies ignore plasticity in silk properties. A better understanding of silk plasticity could clarify the relative importance of chemical composition versus processing of silk dope for silk properties. It could also provide insight into how control of silk properties relates to spider ecology and silk uses. We compared silk plasticity (defined as variation in the properties of silk spun by a spider under different conditions) between three spider clades in relation to their anatomy and silk biochemistry. We found that silk plasticity exists in RTA clade and orbicularian spiders, two clades that differ in their silk biochemistry. Orbiculariae seem less dependent on external spinning conditions. They probably use a valve in their spinning duct to control friction forces and speed during spinning. Our results suggest that plasticity results from different processing of the silk dope in the spinning duct. Orbicularian spiders seem to display better control of silk properties, perhaps in relation to their more complex spinning duct valve.  相似文献   

19.
萼片是番茄花和果实的重要组成部分,影响着果实的商品性。本试验以40份不同类型番茄为材料,对萼片发育过程、形态描述指标及形态多样性进行研究。结果表明,番茄萼片属于宿萼,其形态随着花和果实的发育而变化,表现为闭合、微开、展开、收合、微开、变形到定形,定形萼片呈现包被、基平、上翘、直立和上卷5种状态;对定形萼片7个形态性状观测表明,变异系数由大到小依次为萼片卷曲度(84.43%)、萼片面积(45.54%)、上翘度(40.93%)、形状系数(36.05%)、萼片长(35.02%)、萼片厚(29.46%)和萼片宽(24.61%)。相关性分析表明,萼片长、萼片宽、萼片厚和萼片面积四者之间均极显著正相关;萼片形状系数(萼片长/萼片宽)与萼片长极显著正相关,而与萼片宽无显著相关关系;萼片卷曲度和上翘度之间极显著正相关,而与其他5个性状没有显著相关关系。主成分分析表明,由萼片长、萼片宽、萼片厚和萼片面积代表的大小性状(PC1),由形状系数代表的形状性状(PC2),以及由卷曲度和上翘度代表的形态性状(PC3)3个主成分对萼片形态变异的累计贡献率达87.50%;用形态性状指标对定形的5种类型萼片形态进行了描述。  相似文献   

20.
The Astigmata, a large and variable group, is still a subject of taxonomic dispute. Particularly, their origin from ancestors of the lower oribatid mites (e.g., Malaconothroidea) seems well documented by many lines of evidence. The structure of spermatozoa has been successfully applied to phylogenetic investigations in many animal groups. The aim of our study was to provide new data on spermatozoon structure in Astigmata and to consider its appropriateness in phylogenetic studies. The study reveals information on spermatozoa in 17 species of Astigmata (11 species studied for the first time) extending our knowledge to 18 species (one species known only from the literature) representing 12 families and 7 superfamilies. Spermatozoa have the same basic structure in all species: cells are multiform and the chromatin forms thin threads embedded directly in the cytoplasm; the acrosome is absent. The cytoplasm in most species contains electron-dense lamellae, varying in both number and arrangement within the cell. In Sarcoptoidea, electron-dense tubules in contact with lamellae margins were also observed in Psoroptidae (Psoroptes equi), whereas in two representatives of Sarcoptidae (Notoedres cati and Sarcoptes scabiei), only electron-dense tubules were found. In two species, Canestrinia sellnicki (Canestrinioidea: Canestriniidae) and Scutulanyssus obscurus (Analgoidea: Pteronyssidae), neither lamellae nor tubules were present. The mitochondria in a spermatozoon are usually gathered at the cell periphery and their structure is usually modified to form so-called mitochondrial derivatives. The chromatin threads are an autapomorphy strongly supporting the monophyly of Astigmata. As spermatozoa vary considerably between species in Astigmata, we deduce that sperm structure may be useful for phylogenetic analyses within the group. Several conclusions concerning the affinities within Astigmata are presented. Spermatology seems to be unhelpful, however, in questions on the origin of Astigmata (particularly for Astigmata-Oribatida relationships), since their sperm do not possess synapomorphies with sperm of the remaining groups of Acariformes, i.e., Endeostigmata, Prostigmata, and Oribatida.  相似文献   

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