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1.
A new bittersweet species, Celastrus obovatifolius X. Y. Mu & Z. X. Zhang (Celastraceae) is described from China. It is morphologically most similar to C. orbiculatus Thunb., but differs in having lamellate pith, obovate leaves, flower stalk with an articulation in its upper half, and terminal and axillary inflorescences. This is the first study using scanning electron microscope (SEM) to study the seed micromorphology of Celastrus L., which can provide valuable characters for species identification in the genus.  相似文献   

2.
Microtropis shenzhenensis L. Chen & F. W. Xing sp. nov. (Celastraceae), a new species from Shenzhen, China, is described and illustrated. It is compared with the morphologically similar species M. tetragona.  相似文献   

3.
Brachymenium deceptivum, known only from the type specimen, is described from Ethiopia. It is immediately distinguished from all other species of the genus by its complete lack of an exostome.  相似文献   

4.
Two new species, Rhus neoglutinosa M. Gilbert (Anacardiaceae) and Teclea borenensis M. Gilbert (Rutaceae) are described in preparation for the forthcoming Flora of Ethiopia.  相似文献   

5.
Chassalia magnificens, a new species from the Albertine Rift in eastern Democratic Republic of Congo, is described and illustrated. The species is recognised inter alia by its large stipules and montane habitat. Chassalia chrysoclada is a new combination for a widespread, but hitherto overlooked, central African species originally described in the genus Psychotria. Chassalia chrysoclada is related to C. pteropetala (K. Schum.) Cheek but lacks the bicostate twigs and dorsally winged corolla lobes of that species.  相似文献   

6.
Michelia xianianhei Q. N. Vu, a new species of Michelia from Dien Bien Province, northern Vietnam is described and illustrated. Michelia xianianhei is closely related to M. balansae (Aug. DC.) Dandy but differs mainly in the young twigs, petioles, terminal buds and brachyblasts being densely greyish silky hairy, 9–11 yellowish tepals, bigger fruit, and shorter fruiting gynophore.  相似文献   

7.
Dombeya kefaensis Friis & Bidgood sp. nov., is described from a mosaic of humid montane forest, forest margins, evergreen bushland and farmland of the Kefa Region, SW. Ethiopia. The new species belongs to a group of species in Dombeya subgen. Dombeya with several other endemics in that part of Ethiopia. Among the Ethiopian species of Dombeya subgen. Dombeya it resembles especially D. aethiopica in indumentum and flower colour, but differs in leaf-morphology and habit; it resembles D. buettneri in habit, but differs in the leaf apex being broadly acute to rounded, the sepals and petals longer, and the style having a notable indumentum in more than the basal half. Recent studies have confirmed that a number of taxa belonging to other genera and families are restricted to the Kefa Region and adjacent parts of SW. Ethiopia which confirms the importance of the area as a local centre of diversity.  相似文献   

8.
Ten sesquiterpenoids (1-10), with a dihydro-beta-agarofuran skeleton, were isolated from Maytenus cuzcoina (Celastraceae). Their structures were elucidated on the basis of spectral analysis, including homo- and heteronuclear correlations NMR experiments (COSY, ROESY, HMQC and HMBC), and chemical correlations. The compounds have been tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), as a test for potential cancer chemopreventive agents. Compounds 1-3, 6 and 7 showed strong inhibitory effects on EBV-EA induction (100% inhibition at 1000 mol ratio/TPA). Their structure-activity relationship is discussed.  相似文献   

9.
This work describes a comparative qualitative and quantitative chemical analysis of Maytenus ilicifolia and Maytenus robusta (Celastraceae), extracts by high-resolution gas chromatography (HRGC), using external standards as the method of determination and thin layer chromatographic (TLC). The results show that both plants have a similar chromatographic profile. However, M. robusta exhibited about three times higher concentration of triterpene friedelin than M. ilicifolia.  相似文献   

10.
Thirty-one Acetobacter strains obtained from culture collections and 45 Acetobacter strains isolated from Indonesian sources were investigated for their phenotypic characteristics, ubiquinone systems, DNA base compositions, and levels of DNA-DNA relatedness. Of 31 reference strains, six showed the presence of ubiquinone 10 (Q-10). These strains were eliminated from the genus Acetobacter. The other 25 reference strains and 45 Indonesian isolates were subjected to a systematic study and separated into 8 distinct groups on the basis of DNA-DNA relatedness. The known species, Acetobacter aceti, A. pasteurianus, and A. peroxydans are retained for three of these groups. New combinations, A. orleanensis (Henneberg 1906) comb. nov., A. lovaniensis (Frateur 1950) comb. nov., and A. estunensis (Carr 1958) comb. nov. are proposed for three other groups. Two new species, A. indonesiensis sp. nov. and A. tropicalis sp. nov. are proposed for the remaining two. No Indonesian isolates were identified as A. aceti, A. estunensis, and A. peroxydans. Phylogenetic analysis on the basis of 16S rDNA sequences was carried out for representative strains from each of the groups. This supported that the eight species belonged to the genus Acetobacter. Several strains previously assigned to the species of A. aceti and A. pasteurianus were scattered over the different species. It is evident that the value of DNA-DNA relatedness between strains comprising a new species should be determined for the establishment of the species. Thus current bacterial species without data of DNA-DNA relatedness should be reexamined for the stability of bacterial nomenclature.  相似文献   

11.
The terrestrial diatom Microcostatus schoemanii sp. nov. is described from dry soils of the Faan Meintjies Nature Reserve (North‐West Province, South Africa). Microcostatus cholnokyi sp. nov. and Microcostatus angloensis sp. nov. are described from sandy soils at a colliery near the town of Kriel (Mpumalanga Province, South Africa). The morphology of these taxa is examined using both light and scanning electron microscopy and new taxa are compared with similar species. In M. schoemanii the density of the striae combined with the valve outline and the distance between the central raphe endings are the main distinguishing morphological features. M. cholnokyi is differentiated by the presence of a conopeum and the distinct structure of the microcostae. M. angloensis is similar to M. schoemanii but differentiated by the shape of the cell and the apices, the angle of striation and the distance in between the proximal raphe endings.  相似文献   

12.
From the aerial parts of Maytenus disticha, we have isolated 9beta-benzoyloxy-1alpha,2alpha,6beta,8alpha,15penta-acetoxy-dihydro-beta-agarofuran (1) and from seeds of Maytenus boaria 9beta-furoyloxy-1alpha,6beta,8alpha-triacetoxy-dihydro-beta-agarofuran (2). These compounds and their MeOH and hexane/ethyl acetate (1:1 v/v) extracts were evaluated for their effects on the fall armyworm (Spodoptera frugiperda). Toosendanin, a commercial insecticide derived from Melia azedarach was used as a positive control. When tested for activity using neonate larvae in a nochoice artificial diet bioassays, the agarofurans 1, 2 and toosendanin as well as the MeOH and hexane/EtOAc extracts caused significant growth inhibitory effects with GC50 of 7.55; 3.84; 1.75; 14.0 and 7.3 ppm at 7 days, respectively. Compounds 1 and 2 caused 100% larval mortality at 25 and 15 ppm, respectively. MeOH and hexane/EtOAc extracts caused 100% larval mortality at 25.0 ppm, respectively, they also increased the development time of surviving larvae and a significant delay for the time of pupation and adult emergence. These compounds showed comparable potency of activity with toosendanin. Acute toxicity against adults of S. frugiperda was also found, for hexane/EtOAc extract and 2 had the most potent activity with LD50 value of 4.7 and 1.9 ppm, respectively. MeOH extract, hexane/EtOAc extract, 1 and 2 caused acetylcholinesterase inhibition with 78.0, 89.2, 79.3 and 100% inhibition at 15.0 ppm, respectively. Therefore, the furoyloxy agarofuran may be responsible for the insecticidal activity of these plants.  相似文献   

13.
14.
Two new species of Mallomonas (Chrysophyceae, Mallomonadaceae) are described from tropical lakes. M. fenestrata sp. nov. was found in Lago Tupé (Brazil) and M. perforata sp. nov. in Lake Danau Bratan (Indonesia), Negril ponds (Jamaica) and Marondera ponds (Zimbabwe).  相似文献   

15.
Protoplasma - Reproduction in flowering plants is closely related to the megagametophyte, since the megagametophyte is involved in pollen tube reception and contains the two female...  相似文献   

16.
17.
Anoectochilus nandanensis, a new species from northern Guangxi, China, is described and illustrated. It is similar to A. emeiensis K. Y. Lang in habit, but distinguished by the size of the plant, leaves and lateral sepals, as well as the flanges of the mesochile.  相似文献   

18.
In ‘Flora of China’, the combination ‘Gymnosporia graciliramula (S. J. Pei & Y. H. Li) Q. R. Liu & Funston’ was proposed, but this name was not validly published in 2008 because the presumed basionym Maytenus graciliramula S. J. Pei & Y. H. Li was not published in 1979 as stated, but in 1981, contrary to Article 33.4 of ICBN. Meanwhile, two older names, M. thyrsiflora S. J. Pei & Y. H. Li and M. pseudoracemosa S. J. Pei & Y. H. Li, were listed as synonyms in conflict with article 52.3 of ICBN. In this article, we propose a new combination G. thyrsiflora (S. J. Pei & Y. H. Li) W. B. Yu & D. Z. Li that is the correct name when G. thyrsiflora, M. pseudoracemosa and M. graciliramula are treated as a single species in Gymnosporia.  相似文献   

19.
Two new species collected in northern Thailand are herein described and discussed. Tortulomyces thailandicus is the type of a new genus characterized by a combination of such features as a dense subiculum, non-ostiolate ascomata, two kinds of paraphyses (filiform and bead-like), and 1-septate, brown ascospores. Nitschkia siamensis has non-ostiolate, turbinate and stalked ascomata and hyaline, often slightly curved, 1-septate ascospores.  相似文献   

20.
The present phytochemical investigation on Maytenus guianensis led to the isolations of nine triterpenes, including friedelanes, friedo-nor-oleanane, oleanane and ursane and one steroid. All of them were isolated from this plant for the first time. The presences of friedo-nor-oleanane triterpenoids might be employed as the common characteristic constituents of both Hippocrateaceae and Celastraceae family.  相似文献   

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