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1.
As a result of a recent alpha-taxonomic study of the genusMagnolia s. str. in Mexico and Central America, four new species and four new subspecies ofMagnolia sect.Theorhodon are proposed, includingM. iltisiana, M. panamensis, M. tamaulipana, M. sororum subsp.lutea, andM. pacifica, consisting of three subspecies:pacifica, pugana, andtarahumara. Additionally, a new combination,M. guatemalensis subsp.hondurensis, is made, and a new section,M. sect.Splendentes, is erected for the Caribbean species. The results have implications for understandingMagnolia biogeography, andM. tamaulipana has potential for horticulture in temperate zones. Keys to genera, sections, and species, and maps of species distributions are presented.Magnolia grandiflora L. andM. schiedeana Schltdl. are lectotypified. Como resultado de un estudio alfa-taxonómico reciente del géneroMagnolia s.str. en México y Centro América, se proponen cuatro especies nuevas y cuatro subespecies nuevas deMagnolia sect.Theorhodon, incluyendoM. iltisiana, M. panamensis, M. tamaulipana, M. sororum subsp.lutea y.M. pacifica, la última consiste de tres subespecies:pacifica, pugana ytarahumara. Adicionalmente, se hace la combinaciónM. guatemalensis subsp.hondurensis y se erigeM. sect.Splendentes para las especies del Caribe. Los hallazgos tienen implicaciones en el entendimiento de la biogeografia deMagnolia y.M. tamaulipana tiene potencial en la horticultura de zonas templadas. Se presentan claves para géneros, secciones y especies, y mapas de distribución para las especies.Magnolia grandiflora L. yM. schiedeana Schltdl. son lectotipificadas.  相似文献   

2.
3.
Our recent molecular phylogenetic study revealed a previously unrecognized clade of six species that is sister to Elaphoglossum. Within this clade, four species are currently classified in Bolbitis, one in Lomagramma, and one in Acrostichum. For this clade, we propose the name Mickelia, with M. nicotianifolia as the type species. We also make new combinations for the species in our phylogenetic study shown to belong to Mickelia (M. bernoullii, M. guianensis, M. hemiotis, M. nicotianifolia, M. oligarchica, and M. scandens) and two other species believed to belong to the clade based on morphology (M. lindigii, M. pergamentacea). A new hybrid and two new species are also described (M. ×atrans, M. furcata, and M. pradoi). In total, Mickelia consists of ten species and one hybrid. It is entirely neotropical. We provide a key to the genera of bolbitidoid ferns and a synopsis of Mickelia that gives for each species a complete synonymy, geographical distribution, comparative discussion, and illustration.  相似文献   

4.
Four new species are described and discussed: from BoliviaM. (sect.Habbasia ser.Setosae)huanchacae; from SE brazilM. (sect.Habbasia ser.Pachycarpae)chiliomera andM. (sect.Mimosa)murex; and from EcuadorM. (sect.Mimosa subser.Polycarpae)Loxensis. The two Brazilian species are illustrated.  相似文献   

5.
Seven new species ofMascagnia are described:M. tomentosa from southern Mexico and Central America;M. arenicola from the Guianas;M. riparia, M. tucuruensis, andM. velutina from Brazil;M. boliviana from Bolivia; andM. australis from Argentina and Paraguay. These novelties were previously included in the “M. sepium-complex,” an omniumgatherum comprising superficially similar yellow-flowered taxa.  相似文献   

6.
Figure 2a–r of the above article is reprinted here at the request of the author because the print quality was not up to standard in the issue. Fig. 2a–r. Localization of 28S rDNA (white arrowheads) by fluorescence in situ hybridization of preparations from various Myrmecia species with different chromosome numbers. a–d, i–m Hybridized in situ and propidium iodide-stained chromosomes. e–h, n–r 4’,6-diamidino-2-phenylindole-stained chromosomes. a, e M. croslandi (2n=4). b, f M. pilosula (2n=22); the inset in b shows repeated layers of rDNA-positive signals in C-band. c, g M. pilosula (2n=23). d, h M. gulosa (2n=38). i, n M. forficata (2n=52). j, o M. mandibularis (2n=56). k, p Myrmecia sp. cf. M. arnoldi (2n=60) i, q M. occidentalis (2n=64) m, r M. simillima (2n=70). Bars represent 10 μm. The long bar in h applies also to d; the short bar in r to all other panels Chromosoma (1996) 105:190–196 Received: 22 March 1996; in revised form: 3 June 1996 / Accepted: 4 June 1996  相似文献   

7.
Les vingt-quatre espèces actuellement attribuées au genre Megalocoleus sont réexaminées après étude de tous les types disponibles. Les genitalia mâles et femelles apportent des caractères discriminants beaucoup plus fiables que les caractères externes et sont souvent indispensables pour séparer les espèces. Quelques caractères externes se révèlent néanmoins utiles mais ces derniers sont particulièrement difficiles à apprécier sur les spécimens qui ne sont pas en parfait état. Au terme de cette revue, il apparaît que le genre ne pourra être correctement défini qu’après étude de toutes les espèces décrites dans le genre voisin Amblytylus. Les modifications suivantes peuvent être néanmoins proposées dès à présent:– Réhabilitation d’une espèce, Megalocoleus krueperi (Reuter, 1879) bona species; en conséquence, M. satrapes Horváth, 1907 et M. binotatus (Wagner, 1953), auparavant synonymes de M. lunula, deviennent synonymes de M. krueperi (Reuter, 1879). – Mise en synonymie de 8 espèces: M. hungaricus Wagner, 1944 n. syn. de M. naso (Reuter, 1879); M. ocrensis Wagner, 1972 n. syn. de M. exsanguis (Herrich-Schaeffer, 1835); M. bifidus Wagner, 1973 n. syn. et M. fasciatus Wagner, 1969 n. syn. de M. lunula (Fieber, 1861); M. hirsutus Drapolyuk, 1991 n. syn. de M. signoreti (Reuter, 1879); M. confusus Wagner, 1958 n. syn. et M. pericarti Linnavuori, 1970 n. syn. de M. molliculus (Fallén, 1807). – Exclusion du genre Megalocoleus de quatre espèces; trois sont mises en synonymie: M. femoralis (Reuter, 1879), n. syn. de Tinicephalus hortulanus (Meyer-Dür, 1843), M. fumanae Wagner, 1974 n. syn. de Tinicephalus croceus Wagner 1969, M. servadeii Wagner, 1954 n. syn. d’Amblytylus tarsalis Reuter, 1894; une espèce, M. atricornis devient Tinicephalus atricornis (Wagner, 1965) n. comb. Une clé d’identification pratique (en français et en anglais), basée sur des caractères externes, tente de séparer les 14 espèces de Megalocoleus que le genre compte après cette étude.  相似文献   

8.
Mary E. Endress 《Brittonia》2004,56(4):307-313
Three new species ofMalouetia (Apocynaceae) are described and illustrated:M. amazonica andM. pumila from Brazil andM. gentryi from Peru.Malouetia amazonica grows in inundated igapó forest, whereas the other two are found in non-inundated habitats:M. pumila incampa fechada, andM. gentryi in upland forest.  相似文献   

9.
【背景】作为临床最常见的非结核条件致病分枝杆菌,脓肿分枝杆菌(Mycobacteroides abscessus)因其天然、多耐药等特性成为目前临床治疗的一大挑战。作为分枝杆菌限制性营养元素——铁摄取的关键系统,分枝杆菌素(mycobactin,MBT)、羧基分枝杆菌素(carboxymycobactin,cMBT)与病原分枝杆菌的毒力、耐药等密切相关。【目的】丰富分枝杆菌MBT、cMBT结构数据,探究MBT在致病分枝杆菌起源过程中的演化规律。【方法】在MALDI-TOF-MS与FT-MS/MS解析脓肿MBT、cMBT结构的基础上,进一步开展其活性分析与生物合成基因簇比较基因组分析。【结果】虽然脓肿分枝杆菌MBT、cMBT母核修饰模式与海洋分枝杆菌最相似,R1、R2、R3、R5等位置的修饰完全相同,而且脂肪酸链均位于R4位置;但脂肪酸链长度不同[C10-17 (MBT)、C4-8 (cMBT)],为新结构。Fe-cMBT不仅以浓度依赖方式促进脓肿分枝杆菌生长,而且利用效率显著高于FeCl3,相关结果表明MBT-cMBT是脓肿分枝杆菌高效获取铁元素的关键系统。与MBT结构结果一致,mbt-1基因簇共线性分析及mbt-1mbt-2系统发育分析结果均表明脓肿分枝杆菌与海洋分枝杆菌(M.marinum)亲缘关系最近,而非结核分枝杆菌(M.tuberculosis)或耻垢分枝杆菌(M.smegmatis) (基于16S rRNA基因序列分析)。进一步分析发现,M.marinumM.tuberculosisM.bovis等病原分枝杆菌脂肪酸链长度变化范围仅4 C,而M.abscessusM.fortuitumM.aviumM.smegmatis等条件致病与非致病菌的脂肪酸链长度变化范围为7-11 C,暗示MBT同系物脂肪酸链长度变化范围与分枝杆菌不同生活方式、环境之间可能存在关联。【结论】作为获取铁元素的关键系统,具有独特结构的脓肿分枝杆菌MBT-cMBT在致病、耐药等方面的作用及起源、演化规律值得深入研究。  相似文献   

10.
The genus Meira Jacquelin du Val 1852 is revised, four lectotypes and a neotype are designated, a new synonymy is proposed and four new species from France – one from Alpes-Maritimes (Meira alpina n. sp.), two from Var (M. echinoides n. sp. and M. teloniensis n. sp.), one from Vaucluse (M. germanni n. sp.) and one from Italy, from Abruzzo (M. osellai n. sp.) are described,. Synonyms, bibliographic and ecological data are provided. Whole-body photos of the types of the old species and of the four new species, drawings of systematically important characters, keys and distribution maps are also presented.  相似文献   

11.
Abstract

The Old World syrphid genus Merodon Meigen 1803 is highly species-diverse and has a significant number of endemic species in the circum-Mediterranean area. The present study reports on taxonomic changes resulting from the examination of adult Merodon specimens collected in 15 Turkish provinces during the period 1992 to 2002, and provides new faunistic data. Merodon ilgazense n. sp. is described. Four species of Merodon new to Turkey are recorded: M. armipes Rondani 1843, M. auronites Hurkmans 1993, M. bessarabicus Paramonov 1924 and M. chalybeatus Sack 1913. Lectotypes are designated for two taxa: M. chalybeatus Sack 1913 and M. clunipes Sack 1913. Merodon italicus Rondani 1845 rev. stat. is reinstated as a valid species. Following a detailed study of the type material in different entomological collections, the status of 10 taxa is revised and five new synonymies are proposed: M. albonigrum Vuji Radenkovi &; S?imi 1996 n. syn. (=junior synonym of M. chalybeatus Sack 1913); M. alexeji Paramonov 1925 n. syn. (=junior synonym of M. serrulatus Wiedemann in Meigen 1822); M. aureotibia Hurkmans 1993 n. syn. (=junior synonym of M. vandergooti Hurkmans 1993); M. kaloceros Hurkmans 1993 n. syn. (=junior synonym of M. erivanicus Paramonov 1925); M. longicornis Sack 1913 n. syn. (=junior synonym of M. italicus Rondani 1845).  相似文献   

12.
13.
A new series of pyrazolo[3,4-d]pyrimidine-6-one derivatives (2a–2j) were prepared by using the Biginelli multicomponent cyclocondensation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (1a), different aromatic aldehydes, and urea with a catalytic amount of HCl at reflux temperature. These compounds were characterized by IR, 1H NMR, 13C NMR, and Mass spectral data. In vitro antiamoebic activity was performed against HM1:IMSS strain of Entamoeba histolytica. The results showed that the compounds 2b, 2i, and 2j with IC50 values of 0.37 µM, 0.04 µM, and 0.06 µM, respectively, exhibited better antiamoebic activity than the standard drug metronidazole (IC50?=?1.33 µM). The toxicological studies of these compounds on human breast cancer MCF-7 cell line showed that the compounds 2b, 2i, and 2j exhibited >80% viability at the concentration range of 1.56–50 µM.  相似文献   

14.
A new series of 12 N4-substituted isatin-3-thiosemicarbazones 2a-l has been synthesized, characterized and screened for in vitro cytotoxic, phytotoxic and urease inhibitory effects. All the compounds proved to be active in the brine shrimp bioassay; 2a, 2b, 2d, 2f and 2h-l exhibited a high degree of cytotoxic activity (LD50 = 1.10 × 10? 5 M–3.10 × 10? 5 M). In urease-inhibition assay, compounds 2a, 2b, 2e, 2f, 2h-j and 2l proved to be potent inhibitors displaying relatively much greater inhibition of the enzyme with IC50 values ranging from 20.6 μM to 50.6 μM. Amongst these, 2a and 2f were found to be the most potent ones exhibiting pronounced inhibition with IC50 value 20.6 μM. All the synthetic compounds showed weak to moderate (10–40%) phytotoxicity at the highest tested concentration (500 μg/mL) indicating their usefulness as inhibitors of soil ureases.  相似文献   

15.
On the basis of Rosen's representation of (M, R)-systems as sequential machines (Rosen,Bull. Math. Biophys.,26, 103–111, 1964), the existence of projective limits in categories of general (M, R)-systems is proved.  相似文献   

16.
【背景】利迪链霉菌(Streptomyces lydicus)对多种作物均有较好的促生效果,且对病原真菌具有广谱抑制作用,但该菌对细菌性青枯病的防控研究较少。【目的】探究利迪链霉菌M01能否促进番茄生长并抑制番茄青枯病,以及M01对番茄生长的影响是否通过影响根际细菌群落结构实现。【方法】采用温室盆栽试验和扩增子高通量测序技术研究M01对番茄生长、青枯病发病率及根际细菌群落组成的影响。【结果】施用利迪链霉菌M01的番茄植株鲜重、干重、株高、用土壤与作物分析开发(soil and plant analyzer develotrnent, SPAD)方法测量的叶绿素浓度、根系活力和植株P含量比对照分别提高了22.7%、12.5%、16.0%、28.1%、18.4%和17.9%,其中对株高、SPAD值和植株磷含量影响显著(P<0.05)。M01处理延缓了番茄青枯病的发病时间,接种9周后发病率比对照降低了41.8%。此外,M01对番茄根际细菌群落无显著影响(门水平群落组成,P=0.4;属水平群落组成,P=0.4)。【结论】利迪链霉菌M01可促进番茄植株生长并抑制番茄青枯病,利迪链霉菌M01对番茄生长的影响并非通过调控根际细菌群落实现。  相似文献   

17.
苦槛蓝叶中的黄酮类化合物   总被引:2,自引:0,他引:2  
为了解苦槛蓝(Myoporum bontioides A.Gray)的化学成分,采用色谱分离技术从苦槛蓝叶片中分离得到11个黄酮类化合物。通过波谱分析,他们的结构分别鉴定为:桔皮素(1)、甜橙素(2)、5,4′-二羟基-6,7,8,3′-四甲氧基黄酮(3)、4′,5,7,8-四甲氧基黄酮(4)、去甲基川陈皮素(5)、5-羟基-6,7,3′,4′-四甲氧基黄酮(6)、3′,4′,5,6,7,8-六甲氧基黄酮(7)、二氢山柰酚(8)、木犀草素(9)、3′,4′,5,7-四羟基-3-甲氧基黄酮(10)和芹黄素(11)。除化合物9之外,其他化合物均为首次从苦槛蓝叶片中分离得到。孢子萌发法测定结果表明,化合物1,2,8和9对香蕉炭疽菌(Colletotrichum musae)具有较好的抑菌活性。这为苦槛蓝叶片中有效成分的利用提供了理论依据。  相似文献   

18.
J. Dan Skean 《Brittonia》2000,52(2):191-195
Mecranium juddii is described and illustrated. It is known only from 1650–1700 m elevation in the Ravine du Sud on the northern slopes of Morne Formon in Macaya National Park, Haiti.Mecranium juddii is a member of theM. multiflorum complex and is phenetically most similar toM. revolutum andM. alpestre, which differ fromM. juddii in stem indumentum or leaf size and shape.  相似文献   

19.
Phytochemical investigations on the n-BuOH-soluble fraction of the whole plant of Buddleja davidii led to the isolation of the phenylpropanoid glycosides 1-10. Their structures were determined by 1D and 2D NMR spectroscopic techniques. All the compounds showed potent antioxidative activity in three different tests, with IC50 values in the range 4.15-9.47 μM in the hydroxyl radical (˙OH) inhibitory activity test, 40.32-81.15 μM in the total ROS (reactive oxygen species) inhibitory activity test, and 2.26-7.79 μM in the peroxynitrite (ONOO?) scavenging activity test. Calceolarioside A (1) displayed the strongest scavenging potential with IC50 values of (4.15?±?0.07, 40.32?± 0.09, 2.26?±?0.03μM) for ˙OH, total ROS and scavenging of ONOO?, respectively.  相似文献   

20.
The western Palaearctic species of the genus Mesoleptus Gravenhorst 1829 are redescribed and keys are given for their identification. Also a key for the identification of the three stilpnine genera (Atractodes, Mesoleptus, and Stilpnus) is given and the biology of the genus is discussed shortly. The following species are described as new: Mesoleptus hispanicus n. sp., M. sawoniewiczi n. sp. and M. tunisiensis n. sp. The male of Mesoleptus tobiasi Jonaitis is described for the first time. New combinations is M. incessor (Haliday). New synonyms number 143 and 34 lectotypes are chosen.  相似文献   

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