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Mycobacterium avium comprises organisms that share the same species designation despite considerable genomic and phenotypic variability. To determine the degree and nature of variability between subspecies and strains of M. avium, we used multilocus sequencing analysis, studying 56 genetically diverse strains of M. avium that included all described subspecies. In total, 8,064 bp of sequence from 10 gene loci were studied, with 205 (2.5%) representing variable positions. The majority (149/205) of these variations were found among M. avium subsp. hominissuis organisms. Recombination was also evident in this subspecies. In contrast, there was comparatively little variability and no evidence of recombination within the pathogenic subspecies, M. avium subsp. paratuberculosis, M. avium subsp. avium, and M. avium subsp. silvaticum. Phylogenetic analysis showed that M. avium subsp. avium and M. avium subsp. silvaticum strains clustered together on one branch, while a distinct branch defined M. avium subsp. paratuberculosis organisms. Despite the independent origin of these pathogenic subspecies, an analysis of their rates of nonsynonymous (dN) to synonymous (dS) substitutions showed increased dN/dS ratios for both: 0.67 for M. avium subsp. paratuberculosis and 0.50 for M. avium subsp. avium/M. avium subsp. silvaticum, while the value was 0.08 for M. avium subsp. hominissuis organisms. In conclusion, M. avium subsp. hominissuis represents a diverse group of organisms from which two pathogenic clones (M. avium subsp. paratuberculosis and M. avium subsp. avium/M. avium subsp. silvaticum) have evolved independently.  相似文献   

3.
本文运用色谱/质谱/计算机联用方法,对长江三角洲地区石荠苧属Mosla 5种植物进行分析比较,发现这5个种在精油成分的组成上基本可分为两个类型:一个类型含有大量的香荆芥酚和其他单萜类化合物,倍半萜成分很少,酚酯类化合物几乎没有;另一个类型则在精油中含有大量的倍半萜和酚酯类化合物。笔者在化学分子水平上探讨了它们的种间亲缘关系和可能的演化途径。  相似文献   

4.
The chestnut-shouldered fairy-wrens comprise a subgroup of four species in the genus Malurus (Passeriformes: Maluridae). Collectively, they are widespread across the Australian continent but phenotypic variation is strongly structured geographically in just one species, M. lamberti. Earlier phylogenetic analyses of this group have been limited to one or two individuals for each species and have not represented all currently recognised subspecies of M. lamberti. Historically, the taxonomy and nomenclature of the M. lamberti complex has been debated, in part because of morphological similarities among its subspecies and another member of the group, M. amabilis. We reconstructed the phylogeny of all four species of chestnut-shouldered fairy-wrens including all four subspecies of M. lamberti using a mitochondrial gene (ND2), five anonymous nuclear loci and three nuclear introns. Phylogenetic analysis of the mitochondrial ND2 gene nests M. amabilis within M. lamberti rendering the latter paraphyletic. Individual nuclear gene trees failed to reliably resolve each of the species boundaries or the phylogenetic relationships found in the mtDNA tree. When combined, however, a strongly supported overall topology was resolved supporting the monophyly of M. lamberti and its sister species relationship to M. amabilis. Current subspecific taxonomy of M. lamberti was not concordant with all evolutionary lineages of M. lamberti, nominotypical M. l. lamberti being the only subspecies recovered as a monophyletic group from mtDNA. Some genetic structuring is evident and potential barriers to gene flow are discussed.  相似文献   

5.
本文对我国西南地区叉苔科(Metzgeriaceae)进行了订正,共计2属7种、1亚种、1变种。对西藏、横断山脉及邻区标本作了研究,把喜马拉雅叉苔Metzgeria himalayensis Kashyap并于平叉苔日本亚种M. conjugata subsp. japonica(Hatt.)Kuwah.;把中华叉苔M. sinensis Chen作为狭尖叉苔M. consanguinea Schiffn.的异名。我国东北记载的长梗毛叉苔Apometzgeria longifrondis(Gao)Chang根据其特征,应归于毛叉苔细肋变种A. pubescens(Schrank)Kuwah. var. kinabaluensis Kuwah.本文还报道2个中国新分布种:蓝叉苔M. darjeelingensis Kuwah.背胞叉苔M. novicrassipilis Kuwah.  相似文献   

6.
Seven species were recognized in Mosla in China. M. pauciflora (C. Y. Wu) C. Y. Wu et H. W. Li is an allotetraploid (2n=36 ), while the other six species are diploids (2n=18). Cluster analysis based on allozyme data from 28 loci of 15 enzyme systems reveals that the six diploid species formed three species pairs. M. cavaleriei Lévl.is closely related to M. dianthera (Buch.-Ham. ex Roxb. ) Maxim., M. chinensis and M. hangchouensis Matsuda are sibling species, and M. scabra (Thunb.) C. Y. Wu et H. W. Li is allied to M. soochouensis. Although M. cavaleriei and M. dianthera are close relatives, considerable genetic divergence has been detected between them. One third of alleles are unique to either of them, and 28.6 % of their loci have different alleles fixed. The average genetic identity ( 1 ) between populations of these two species is 0.770, and the average genetic distance (D) is 0.261. M. scabra and M. soochouensis are the least divergent species pair (I =0.979, D=0.025). No completely divergent locus was detected, and the percentages of unique alleles are 11.1% to M. scabra and 16.7 % to M. soochouensis. This finding indicates that a high level of genetic differentiation is unnecessarily a prerequisite of speciation. A moderate divergence is detected between M. chinensis and M. hangchouensis (I=0.899, D=0.107, and 7.1% of completely diverged loci) yet the latter harbors four times as many unique alleles (45.1% ) as the former does(11.8 % ). Compared to the genetic divergence between M. scabra and M. soochouensis, M. dianthera and M. hangchouensis and may well been undergoing active speciation have the high genetic distance betweenpopulations (0.034 and 0.026 respectively).  相似文献   

7.
通过对中国纩蚜属的研究,作者提出纩蚜属的现代地理分布呈岛状分布的格局;并推测该属的起源中心可能在欧洲,现代分化中心可能在中国的横断山脉地区。从动物地理的角度,探讨了该属内的系统发育关系。同时,发现一新种,即云杉纩蚜Mindaurspiceasuctusspnov.。正模为无翅孤雌蚜,副模为5只有翅孤雌蚜和8只无翅孤雌蚜,分布在云南省昆明市,辽宁省沈阳市和熊岳县。一新亚种,即冷杉纩蚜三圈亚种M.abietinustriprimesensorissp.nov.,正模为有翅孤雌蚜,副模为3只有翅孤雌蚜,分布在云南省丽江市玉龙山。一新纪录种,即冷杉纩蚜指名亚种M.abietinusabietinusKoch1856。并且给出种的检索表,模式标本存放在中国科学院动物研究所标本馆。  相似文献   

8.
The genus Monobellu Cassagnau, 1979 (Collembola) is redefined. Four new species and one new subspecies are described from Pyrenees and Cevennes (France) on the basis of labrum morphology, tubercle arrangement on tergites and chaetotaxy of somites: Monobellu culvu sp. n., Monobellu eduphica sp. n., Monobellu grussei minor ssp. n., Monobellu juu sp. n., and Monobellu rousseti sp. n. The subspecies Monobellu grussei dubiu Deharveng, 1986 is reassigned to specific level. A key to the 14 species and subspecies of Monobellu is given. Except M. g. minor ssp. n. which is present in the Pyrenees and the Massif Central and the widespread M. g. grussei (Denis, 1923), all Monobellu species and subspecies are narrow endemics of the Pyrenean range; their distribution is mapped in details. A phylogenetic analysis is performed, taking into account the high level of polymorphism of some characters and the incomplete genetic isolation between certain subspecies, indicated in the field by the presence of narrow hybrid zones. Though obtained under different assumptions and constraints, the most parsimonious cladograms exhibit only slight differences, and the proposed phyletic reconstruction can be considered as robust. It adequately reflects the known distribution of the species in the Pyrenees, it confirms the monophyly of the species M. grussei and supports, in agreement with field distribution data, the idea that reticulate evolution might have occurred in this taxon. © The Norwegian Academy of Science and Letters  相似文献   

9.
The exploratory and fear behaviours of the black paradise fish M. o. concolor, a subspecies of Macropodus opercularis, were studied and compared with those of an outbred and two inbred populations of M. o. opercularis. Adult females of both subspecies were used in the behaviour tests (open-field, novel-object approach, restricted space), and their behaviour in novel and startling situations was described by recording the sequence of ethologically defined units. It was found that M. o. concolor more often responded passively to novelty and fear-evoking stimuli. In 11 out of 14 test measures they were less active (p less than 0.01 and 0.001) than the outbred M. o. opercularis, but were very similar to our extremely timid strain P. Subtle differences of behaviour units were found between the subspecies, e.g. the absence of interrupted movements and unoriented panic behaviour in M. o. concolor. It is supposed that alternative passive and active strategies represent genetic polymorphism of defensive behaviour.  相似文献   

10.
The subsection Neriiflora Sleumer is one of the largest subsections of Rhododendron subgenus Hymenanthes, containing 27 species, 8 subspecies and 24 varieties. All the species are divided into four groups according to morphological characters, relationships among the species and their geographical distribution. The evolution and relationships of the group are discussed. The Group D is of highly specialized morphological characters. The subsection has its modern distribution center in the Hengduan Mountains in south-westernChina.  相似文献   

11.
Centranthus DC. is a mediterranean genus comprising 17 taxa (including 9 species and 7 subspecies). Two new subspecies, namely C. longiflorus subsp. atlanticus and C. calcitrapae subsp. trichocarpus , are described. Affinities within the genus are discussed and four species are newly circumscribed; five new infraspecific combinations are made. Vicariance is demonstrated with the aid of two dot maps.  相似文献   

12.
中国小舟蛾属分类研究 (鳞翅目:舟蛾科)   总被引:1,自引:0,他引:1  
武春生  方承莱 《昆虫学报》2003,46(2):222-227
系统整理了小舟蛾属Micromelalopha Nagano, 1916的全部中国种类共10种,包括2新种异小舟蛾M. variata Wu et Fang 和细小舟蛾M.ralla Wu et Fang; 并将M.flavomaculata Tshistjakov 作为邻小舟蛾M.vicina Kiriakoff的亚种,赭小舟蛾秦岭亚种M.aemorrhoidalis cinereibasis Kiriakoff作为指名亚种M.Haemorrhoidalis haemorrhoidalis Kiriakoff的异名处理。文中提供了分种检索表、新种形态描述和外生殖器特征图。模式标本保存在中国科学院动物研究所动物标本馆。  相似文献   

13.
《Journal of Asia》2021,24(4):1301-1312
The hoverfly genus Merodon Meigen, 1803 (Diptera, Syrphidae), which comprises more than 200 species is distributed in the Palaearctic and Afrotropical Region, but one species, Merodon equestris, is a pest of flower bulbs and has been invasive into New Zealand and North America. In this work, the Merodon aurifer species group, a member of the M. avidus-nigritarsis lineage, is revised. The diagnostic characters of the M. aurifer species group, and the morphological differences between M. aurifer Loew, 1862 and M. nudicorpus sp. n. are explained and illustrated, as well as their distribution map. A detailed study of the type material resulted in three new synonyms: M. distinctus Palma, 1863 is a junior synonym of M. aurifer; M. manicatus (Sack, 1938) and M. testacoides Hurkmans, 1993 are junior synonyms of M. testaceus.Lectotypes are designated for two taxa M. aurifer and M. manicatus instead of the erroneously designated types for these species in Hurkmans (1993).  相似文献   

14.
王文采   《广西植物》2007,27(1):1-28
(1)对毛莨科铁线莲属Clematis的铁线莲组sect.Viticella进行了分类学修订,确定此组包含13种,1亚种和2变种(包括2新种和1新变种等级),写出此组的分类学简史和地理分布;将此组划分为3亚组,4系,写出区分组下各级分类群的检索表,以及各种植物的形态描述,地理分布,生长环境等,并附有多幅插图。(2)特产我国东部的单型毛萼铁线莲亚组subsect.Hancockianae(花具4枚平展,不展宽的萼片,雄蕊无毛)被认为此组的原始群。铁线莲亚组subsect.Floridae(花具5-8枚平展,强烈展宽的萼片,雄蕊无毛,花粉具散孔)和湖州铁线莲亚组subsect.Viticellae(花具4枚渐升,多少展宽的萼片,雄蕊花丝常被缘毛,花粉具3沟)可能均由毛萼铁线莲亚组衍生而出。(3)在我国东部集中分布此组的3亚组,3系的8种,1亚种和1变种,这里是此组的分布中心,也可能是此组的起源中心。  相似文献   

15.
The genus Miliusa in Cambodia and Vietnam is reviewed. Cambodia and Vietnam each harbors six species of Miliusa, including three which are described as new to science: one from Cambodia (Miliusa cambodgensis sp. nov.), the other two from Vietnam (M. astiana and M. ninhbinhensis spp. nov.). In addition, a complete nomenclature and relevant information about the Miliusa species previously known from Cambodia and Vietnam are provided, including keys to the Cambodian and Vietnamese species, the designation of a lectotype for M. baillonii and the synonymization of M. balansae var. elongatoides, M. chunii and M. sinensis with M. balansae.  相似文献   

16.
Previous systematic treatments of Menonvillea recognized a group of six morphologically related species, the ‘M. scapigera group,' distinguished by having pinnately lobed leaves and united filaments of median staminal pairs. The number of recognized species ranged from six to two, one with three subspecies. In order to clarify the taxonomy of this group, multivariate and univariate analyses of qualitative and quantitative characters from herbarium specimens were performed. Additionally, to test the morphological results, the phylogenetic relationships and degree of exclusive ancestry were studied using ITS sequences and the genealogical sorting index. Our results support the recognition of three species (M. famatinensis, M. hirsuta, M. scapigera) delimited by a unique combination of qualitative characters. Quantitative characters support the division of the latter species into two subspecies: scapigera and longipes. The molecular data are congruent with the morphology and support the inclusion of M. hookeri within M. scapigera. A key to taxa of the M. scapigera group is presented.  相似文献   

17.
23 species, one subspecies and three varieties have been described or named for the pan-tropical genus Lasianthus Jack (Rubiaceae) in continental Africa. In the present revision thirteen species, five subspecies and one variety are recognized; additionally two hybrids are proposed. Of the previously named taxa, the subspecies is raised to species rank whereas two species are degraded to subspecies and variety status, respectively. Five species are synonymised including two varieties, and four are left with uncertain status, including one variety. The distribution of the genus in Africa consists of two distinct elements: one component is found in the Guineo-Congolian regional centre of endemism and one in the eastern part of Afiomontane Archipelago-like regional centre of endemism. A centre of species diversity is found in Eastern Arc Mts., where six endemic species occur together with L. laxinervis and the more widespread L. kilimandscharicus. Four of the species are strict endemics of the Uluguru Mts. In addition to the presentation of the new section: Lasianthus Sectio Membranacei, sect. nov., this revision contain two hybrids from Uluguru Mts.: L. macrocalyx × pedunculatus and L. cereifizorus × pedunculatus, and following new taxa and new combinations: L. africanus ssp. biokoensis, subsp. nov.; L. africanus ssp. mayumbensis, comb. et stat. nov.; L. kilimandscharicus ssp. glabrescens, ssp. nov.; L. kilimandscharicus ssp. glabrescens var. xanthospermus, comb. et stat. nov.; L. kilimandscharicus ssp. hirsutus, ssp. nov.; L. laxinervis, stat. nov.; L. pedunculatus ssp. angustisepalus, ssp. nov.  相似文献   

18.
张雷  梁琍  冉辉  沈正雄 《动物学杂志》2012,47(4):135-138
报道了角蟾科一新亚种,该亚种具角蟾属特征,与峨眉角蟾种组中的炳灵角蟾(Megophrysbinlingensis)形态特征最为相近,但与该组成员又有明显区别,被命名为炳灵角蟾梵净山亚种(M.b.fanjingmontis subsp.nov.)。本亚种主要鉴别特征为犁骨棱较弱,后端无犁骨齿,上颌有细齿;第一、二指上婚刺细密,趾侧缘膜窄;体腹面斑少,两侧黑褐色长形斑明显;体型较大,雄性头体长大于60.00 mm;趾间具1/3蹼。  相似文献   

19.
Twenty-five strains classified as Mycoplasma mycoides subsp. mycoides LC or subsp. capri have been compared by one-dimensional SDS-PAGE of their cellular proteins. A computerized numerical analysis revealed that the protein patterns of all but two aberrant strains formed one large phenon that separated clearly from representatives of the four other members of the 'M. mycoides cluster' at a similarity level (S) of 66% and which remained undivided at up to 78% S. At higher similarity levels, these strains fell heterogeneously into mixed sub-phenons containing strains of both subspecies. Serological comparisons by immunofluorescence largely confirmed the subspecies designations of the test strains, but also showed that some were serologically intermediate between subsp. mycoides and subsp. capri, being cross-reactive with both. These results confirm and enlarge upon those of our earlier studies indicating the protein-pattern inseparability of subsp. capri and subsp. mycoides LC strains and their distinctiveness from the classical M. mycoides subsp. mycoides SC strains and other members of the 'M. mycoides cluster'. As also recognized by other workers, subsp. mycoides LC and subsp. capri strains appear to comprise one large group, wherein those most readily identifiable as either type lie at either end of a serological spectrum that also contains serologically cross-reactive strains. Our observations therefore suggest the lines along which the three groups classified at present within the species M. mycoides (SC and LC strains of subsp. mycoides; subsp. capri) might eventually be reclassified, subject to direct genomic comparisons.  相似文献   

20.
Following iron-deficient growth, mycobactins and exochelins were isolated from 11 strains of Mycobacterium tuberculosis (including type strains of the virulent H37Rv and avirulent H37Ra organisms) as well as from M. bovis (one strain), M. bovis BCG (two strains), M. africanum (eight strains) and M. xenopi (one strain) but not from M. microti (one strain). The mycobactins from the tuberculosis group (M. tuberculosis, M. bovis and M. africanum) were identical and could each be resolved into four compounds by thin-layer chromatography (TLC) and into several fractions by high-performance liquid chromatography, supporting previous claims that this group is a single taxon. Exochelins were all chloroform-soluble and showed no species specificity; no single exochelin was recognized by TLC that had not been previously seen in M. avium or a related species.  相似文献   

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