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1.
中国弧隔鼠尾草亚属(唇形科)的分布格局 总被引:3,自引:3,他引:0
弧隔鼠尾草亚属(Subg.Salvia Benth.)是中国原产鼠尾草属最大的属下类群,有44种13变种,大多含有与丹参(S.miltiorrhiza)类似的活性化合物成分和药用功效,是具有较高利用前景的野生药用植物资源。从形态学分析,该亚属具备原始类群的主要特征,物种分化明显,是研究鼠尾草属起源和演化的关键材料;从地理分布格局看,该亚属集中分布于青藏高原以及横断山脉的高海拔地区,较少扩散至低海拔的华中与华东,易受环境和全球气候变化的影响,生境人为干扰强烈,资源保护压力较大。据此,对弧隔鼠尾草亚属物种分布区进行了全面调查,结合标本记录,获得该类群具经纬度的物种分布记录2689条,海拔高度记录1007条,分布点涵盖286个县级地区。进一步对亚属内各组、系的水平与垂直分布格局深入分析。结果表明,亚属以横断山为核心区,主要分布于西藏东南至川西一带,零星扩散迁移至河北北部、湖北东部,其狭域分布的特有种比例非常高,占总物种数的45%。在物种海拔分布格局上,亚属内6个系具有替代分布现象,从高海拔的窄域分布物种逐渐过渡到低海拔的宽域分布物种。基于最大熵模型预测的亚属出现概率与物种实际分布范围基本吻合,从单一环境因子与出现概率的关系看,12月降水量、9月降水量、年温度变化范围、海拔、3月最高气温和温度季节性变化系数是影响物种分布的主导环境因子。鼠尾草雄蕊的分化是物种形成和多样性产生的关键因素,亚属内不同类群的分布格局与雄蕊花丝药隔比例的相关性表明,环境因子和传粉者选择可能共同作用形成现有弧隔鼠尾草亚属的分布格局。 相似文献
2.
Polygala pauciramosa, a new species from the Federal District and the state of Goiás is described, illustrated, and compared with related species
of Polygala subgenus Hebeclada. The new species is an herb that grows in seasonally to permanently wet savannas. A key to the species of Polygala subgenus Hebeclada from Goiás state, Brazil is provided. 相似文献
3.
中国淡水硅藻新记录——偏肿内丝藻兴凯变种 总被引:1,自引:0,他引:1
于2016年5月对浙江省仙居国家公园进行藻类多样性调查时,发现了中国淡水硅藻的1个新记录种——偏肿内丝藻兴凯变种[Encyonema ventricosum var.hankensis(Skvortzov) RodionovaPomazkina]。该文采用光镜和扫描电镜对偏肿内丝藻兴凯变种浙江种群的形态特征进行了观察和描述,并将其与该种的其他地理种群及内丝藻属其他相似物种的形态特征进行比较,同时讨论了该物种的生境特征。结果表明:(1)偏肿内丝藻兴凯变种壳面均具明显背腹之分,背缘明显拱起,腹缘轻微波曲;端部呈头状至喙状。(2)偏肿内丝藻兴凯变种浙江地理种群在背部中央区域具一孤点,而其兴凯种群对孤点这一特征未有描述。(3)偏肿内丝藻兴凯变种在俄罗斯的兴凯湖和贝加尔湖等地有分布,该种在中国是首次报道。 相似文献
4.
The sequences of the second internal transcribed spacer (ITS2) of ribosomal DNA (rDNA) were determined for 40 black fly species
from Thailand, belonging to 4 subgenera of the genus Simulium, namely Gomphostilbia (12 species), Nevermannia (5 species), Montisimulium (1 species), Simulium sensu stricto (21 species), and an unknown subgenus with one species (Simulium baimaii). The length of the ITS2 ranged from 247 to 308 bp. All black fly species had high AT content, ranging from 71 to 83.8%.
Intraindividual variation (clonal variation) occurred in 13 species, ranging from 0.3 to 1.1%. Large intrapopulation and interpopulation
heterogeneities exist in S. feuerboni from the same and different locations in Doi Inthanon National Park, northern Thailand. Phylogenetic relationships among
40 black fly species were examined using PAUP (version 4.0b10) and MrBAYS (version 3.0B4). The topology of the trees revealed
two major monophyletic clades. The subgenus Simulium and Simulium baimaii were placed in the first monophyletic clade, whereas the subgenera Nevermannia + Montisimulium were placed as the sister group to the subgenus Gomphostilbia in the second monophyletic clade. Our results suggest that S. baimaii belongs to the malyschevi-group or variegatum-group in the subgenus Simulium. The molecular phylogeny generally agrees with existing morphology-based phylogenies. 相似文献
5.
Four distinct species ofCortinarius referable to subg.Dermocybe are described from the Cooloola Sand-Mass, Queensland; two are formally recognized asC. alkalivirens, spec. nova andC. chromobasis, spec. nova, whilst notes are provided for the other two. Chemical methods and cladistic studies are applied and indicate a new section of the subgenus is required.Australodermocybe sect. nova is proposed. 相似文献
6.
Keisuke Obase Takahito Kobayashi Toshizumi Miyamoto Yutaka Tamai Takashi Yajima 《Mycoscience》2006,47(5):293-297
A species of the genus Inocybe, which has not been recorded previously in Japan, is described and illustrated as a new record. Inocybe nitidiuscula (Britzelm.) Sacc. belongs to the subgenus Inocibium (Earle) Singer. 相似文献
7.
Miscanthus subgen. Rubimons (B. S. Sun) Y. C. Liu et H. Peng, a new subgenus of Miscanthus Anderss. (Poaceae) is established and Miscanthus (Rubimons) villosus Y. C. Liu et H. Peng, a new species of this subgenus from southwest Yunnan, China, is described and illustrated. It is closely related to M. paniculatus (B. S. Sun) S. L. Chen & Renvoize, but differs mainly by its villous panicle axis, long callus hair, lanceolate lower lemma and the consistently longer awn of the upper lemma. 相似文献
8.
Zornia subsessilis, a new species from Serra do Cabral, Minas Gerais State, Brazil, is described and illustrated on the basis of field and herbarium
studies. It belongs to Zornia section Zornia of subgenus Zornia and it appears to be restricted to “campo rupestre” (rocky fields) within the “cerrado” biome. This new species is characterized
by its sessile to subsessile leaves, fruits with articles 4 to 5 mm long and with bristles up to 3.5 mm long. 相似文献
9.
Benjamin W. van Ee Paul E. Berry Ricarda Riina Jorge E. Gutiérrez Amaro 《The Botanical review》2008,74(1):132-165
Initial molecular phylogenetic studies established the monophylly of the large genus Croton (Euphorbiaceae s.s.) and suggested that the group originated in the New World. A denser and more targeted sampling of Croton species points to a South American origin for the genus. The nuclear and chloroplast genomes indicate a different rooting
for the phylogeny of Croton. Although we favor the rooting indicated by the chloroplast data our conclusions are also consistent with the topology inferred
from the nuclear data. The satellite genera Cubacroton and Moacroton are embedded within Croton. These two genera are synonimized into Croton and a new subgenus, Croton subgenus Moacroton, is circumscribed to include them and their allied Croton species. Croton subgenus Moacroton is morphologically characterized by a primarily lepidote indumentum, bifid or simple styles, and pistillate flowers with
sepals that are connate at the base. This newly circumscribed subgenus is found from North America to South America, and in
contrast to the majority of Croton species most of its members are found in mesic habitats. The group is most diverse in the greater Caribbean basin. A molecular
clock was calibrated to the phylogeny using the available Euphorbiaceae fossils. The timing and pattern of diversification
of Croton is consistent with both the GAARlandia and Laurasian migration hypotheses. A single species, Croton poecilanthus from Puerto Rico, is placed incongruently by its nuclear and chloroplast genomes. The possibility of this species being of
hybrid origin is discussed.
相似文献
10.
Passiflora bakhuisensis (plate 1056) a new species of Passiflora L. in subgenus Astrophea (DC.) Mast., supersection Astrophea, section Dolichostemma Killip from Surinam is described; its taxonomy, distribution and cultivation are discussed, and a key to this and related species is provided. A new synopsis of subgenus Astrophea (DC.) Mast., supersections Astrophea and Pseudoastrophea (Harms) Feuillet & J. M. MacDougal is provided. 相似文献
11.
Yukari Mizuta 《Mycoscience》2006,47(6):380-384
Two new species and one new variety of Oudemansiella (Agaricales) from Japan are described and illustrated: (1) Oudemansiella latilamellata sp. nov. (subgenus Xerula, section Radicatae) has relatively broad lamellae and broadly ellipsoid spores with a subacute apex; (2) Oudemansiella rhodophylla sp. nov. (subgenus Xerula, section Radicatae), growing in deciduous forests of Fagus crenata, Quercus crispula, etc., is characteristic in having lamellae tinted reddish; and (3) Oudemansiella amygdaliformis var. bispora var. nov. (subgenus Xerula, section Albotomentosae) is distinguished from the type variety by having two-spored basidia and grows in evergreen oak forests (Castanopsis sieboldii, Quercus glauca, etc.) or bamboo groves. 相似文献
12.
David G. Frey 《Hydrobiologia》1993,262(3):133-144
Examination of many species of Pleuroxus from the entire World has revealed a major dichotomy in morphology, one line related to aduncus: the other to laevis both from Europe. Pleuroxus trigonellus (the type species of the genus) and Peracantha truncata are in two other distinct lines. The new subgenus Tylopleuroxus is proposed for the species related to aduncus, and the subgenus Picripleuroxus for those related to laevis. Tylopleuroxus is primarily Southern Hemisphere in distribution, Picripleuroxus primarily Northern Hemisphere. Evidence thus far suggests that probably most, perhaps all, of the taxa are confined to single
continents or land masses.
Deceased 相似文献
13.
Cyperaceae tribe Cariceae is characterized by both species richness and habitat diversity, making it an ideal system to study
ecological specialization and niche differentiation. We present a phylogenetic hypothesis for the tribe based on nuclear and
chloroplast DNA sequence comparisons (ETS-1f, ITS, trnL intron, trnL-trnF intergenic spacer) for 140 representative species from five continents, and use this hypothesis to suggest patterns of both
niche conservatism and niche differentiation, particularly within the large subgenus Carex. We identify a new major clade, comprising forest species of East Asian Carex section Siderostictae (subgenus Carex) as sister to the rest of tribe Cariceae. Within Carex subgenus Carex, species tolerant of water-saturated habitats occur in only a few, apparently derived groups, with varying species richness.
Clades of predominantly wetland species tend to have broad geographic distribution, often with sister species on different
continents, suggesting recent dispersal. In contrast, species within several clades are predominantly forest specialists with
distinct Asian and North American lineages. Niche segregation along environmental gradients, such as soil moisture or acidity,
is quite common among closely related wetland species, but more difficult to demonstrate within upland forest groups. More
complete sampling of species within both wetland and forest groups, combined with comparable sampling of environmental preferences
and testing against null models, will be needed for more rigorous exploration of the observed patterns. 相似文献
14.
You‐Sheng Chen 《Nordic Journal of Botany》2010,28(6):761-763
Saussurea baoxingensis Y. S. Chen (Compositae, Cardueae), a new species of snow lotus from the Sichuan province, China is described and illustrated. It belongs to subgenus Amphilaena and is allied to S. muliensis. Morphological characteristics that distinguish the new species from S. muliensis are presented and discussed. 相似文献
15.
Traps have been used extensively to provide early warning of hidden pest infestations. To date, however, there is only one type of trap on the market in the U.K. for storage mites, namely the BT mite trap, or monitor. Laboratory studies have shown that under the test conditions (20 °C, 65% RH) the BT trap is effective at detecting mites for at least 10 days for all three species tested: Lepidoglyphus destructor, Tyrophagus longior and Acarus siro. Further tests showed that all three species reached a trap at a distance of approximately 80 cm in a 24 h period. In experiments using 100 mites of each species, and regardless of either temperature (15 or 20 °C) or relative humidity (65 or 80% RH), the most abundant species in the traps was T. longior, followed by A. siro then L. destructor. Trap catches were highest at 20 °C and 65% RH. Temperature had a greater effect on mite numbers than humidity. Tests using different densities of each mite species showed that the number of L. destructor found in/on the trap was significantly reduced when either of the other two species was dominant. It would appear that there is an interaction between L. destructor and the other two mite species which affects relative numbers found within the trap.The British Crowns right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged.This revised version was published online in May 2005 with a corrected cover date. 相似文献
16.
Kunio Sasaki 《Ichthyological Research》1999,46(3):271-279
A new sciaenid,Johnius (Johnieops) philippinus, is described from the Davao Gulf, Mindanao Island Philippines. It differs from all known species of the subgenus in the
combination of 29–32 dorsal fin soft rays, 5–6 scales above and 10–13 scales below the lateral line, 10–12 lower gill rakers,
a broadly rounded anterior snout margin (from dorsal aspect), large eyes (28–35% HL), a narrow interorbital space (23–28%
HL) and well-developed pleural ribs on 11th vertebra. A synopsis of species included in the subgenusJohnieops is provided. 相似文献
17.
四照花亚属(Cornus subg.Syncarpea)隶属于山茱萸科山茱萸属(Cornus),我国该亚属共有5种8亚种。为探讨四照花亚属nrDNA ITS序列的致同进化不完全现象及假基因产生的可能原因,分析了该亚属4种(每种1~2个居群)共21个个体的nrDNA ITS序列。结果表明,这些类群的nrDNA ITS存在多态性,通过分析这些nrDNA ITS克隆序列的G+C含量、5.8S保守基序和二级结构最小自由能,推测其可能存在假基因。系统发育研究结果显示所有nrDNA ITS序列分成5个分支,同一个体的不同拷贝被分别置于两个甚至多个分支中,且不同分支显示了不同种间关系。四照花亚属物种个体内部存在nrDNA ITS不完全致同进化,可能归咎于不完全的世系分选(incomplete lineage sorting)、种间杂交或多倍化等进化事件,从而导致基因组内nrITS区序列出现多态性,同时也导致难以通过外部形态来划分亚属内种间界限。 相似文献
18.
A new soil mite species, Quadroppia (Coronoquadroppia) sezeki sp. n., is described. Adult mites were recorded from moss under a pine tree from a pine forest. The new species differs from
the other species of the subgenus by bearing epimera III+IV with a wide key hole shaped inner border and the shape of frontal
appendage of rostrum. The morphological features of the new species are also compared with those present in closely related
species. 相似文献
19.
Allium subgenus Melanocrommyum (Alliaceae) from Eurasia comprises about 150 mostly diploid species adapted to arid conditions. The group is taxonomically complicated with different and contradictory taxonomic treatments, and was thought to include a considerable number of hybrid species, as the taxa show an admixture of assumed morphological key characters. We studied the phylogeny of the subgenus, covering all existing taxonomic groups and their entire geographic distribution. We analyzed sequences of the nuclear rDNA internal transcribed spacer region (ITS) for multiple individuals of more than 100 species. Phylogenetic analyses of cloned and directly sequenced PCR products confirmed the monophyly of the subgenus, while most sections were either para- or polyphyletic. The splits of the large sections are supported by differences in the anatomy of flower nectaries. ITS data (i) demand a new treatment at sectional level, (ii) do not support the hypotheses of frequent gene flow among species, (iii) indicate that multiple rapid radiations occurred within different monophyletic groups of the subgenus, and (iv) detected separately evolving lineages within three morphologically clearly defined species (cryptic species). In two cases these lineages were close relatives, while in Allium darwasicum they fall in quite different clades in the phylogenetic tree. Fingerprint markers show that this result is not due to ongoing introgression of rDNA (ITS capture) but that genome-wide differences between both lineages exist. Thus, we report one of the rare cases in plants where morphologically indistinguishable diploid species occurring in mixed populations are non-sister cryptic species. 相似文献
20.
Miroslav Barták 《Biologia》2006,61(5):503-508
Rhamphomyia (Lundstroemiella) cervi sp. n. (France), R. (L.) cimrmani sp. n. (Turkey) and R. (L.) speighti sp. n. (France) are described and illustrated. A key to the Palaearctic species of the subgenus Lundstroemiella Frey is given. 相似文献