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1.
PhytoKeys ; 239: 215-228, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550898

RESUMO

Gentianamopanshanensis, a new species of the family Gentianaceae is here described and illustrated. This species is presently known only from the Mopanshan Mountain, Yunnan Province, southwest China. Phylogenetic analysis based on ITS sequence data has shown that this new species is a member of the series Fimbriatae of the section Chondrophyllae. Morphologically, it mostly resembles G.mairei and G.panthaica, but differs clearly from the latter two species in the shape and size of the leaves, and the characters of the corolla throat and plicae.

2.
PhytoKeys ; 246: 251-263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39301118

RESUMO

Xantolisweimingii sp. nov. (Sapotaceae) is described and illustrated from Yunnan, southwest China. The new species is morphologically most similar to X.tomentosa (Roxb.) Raf., but differs from the latter in the ovate or obovate leaves, entirely glabrous corollas, lanceolate, ca. 5 mm long staminodes, fringed at the base. We provided a distribution map and a preliminary conservation assessment for the new species. Additionally, an updated dichotomous key to all known species of Xantolis is presented.

3.
PhytoKeys ; 237: 191-200, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38304345

RESUMO

Isodonxiaoluzhiensis, a new species of the tribe Ocimeae in family Lamiaceae, is described and illustrated. The new species is known only from the type locality, Xiaoluzhi village in Luzhijang dry-hot valley of Yimen County, central Yunnan, southwest China. It is characterized by having a procumbent habit, gracile stems and branches, relatively small leaves and flowers, and the phenology of flowering in winter. The morphological comparisons with its putative closest relatives (I.adenanthus and I.hsiwenii) are also presented.

4.
PhytoKeys ; 241: 91-101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638580

RESUMO

Indigoferajintongpenensis, a new species of the subfamily Papilionoideae of Fabaceae, is described and illustrated from Yunnan, southwest China. The new species is characterised by having a prostrate habit, flexible stems and branches, as well as spreading, sub-basifixed, asymmetrically 2-branched trichomes covering the entire plant, discoid calyx, and racemose inflorescences 6-8-flowered, short, 1-2 (-3.5) cm in length, apparently shorter than the leaf. A distribution map and comparison of morphological diagnostic characters with its morphologically similar species are provided. Additionally, a preliminary conservation assessment of I.jintongpenensis is proposed following IUCN criteria.

5.
Plant Divers ; 46(5): 648-660, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39290888

RESUMO

Relict subtropical coniferous forests in China face severe fragmentation, resulting in declining populations, and some are under significant threat from invasive alien species. Despite the crucial importance of understanding forest dynamics, knowledge gaps persist, particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana. In this study, we investigated the impact of invasive plants on the regeneration of forests dominated by K. evelyniana, a subtropical relict species in southwestern China. For this purpose, we characterized forest dynamics of 160 forest plots featuring K. evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K. evelyniana. We identified four distinct forest types in which K. evelyniana was dominant. We found that radial growth of K. evelyniana trees is faster in younger age-classes today than it was for older trees at the same age. The population structure of K. evelyniana in each forest type exhibited a multimodal age-class distribution. However, three forest types lacked established saplings younger than 10 years old, a situation attributed to the dense coverage of the invasive alien Ageratina adenophora. This invasive species resulted in a reduction of understory species diversity. Additionally, our analysis uncovered a significant negative correlation in phylogenetic relatedness (net relatedness index) between native and invasive alien plant species in eastern Yunnan. This suggests closely related invasive species face heightened competition, hindering successful invasion. Taken together, our findings indicate that successful establishment and habitat restoration of K. evelyniana seedling/saplings require effective measures to control invasive plants.

6.
PhytoKeys ; 225: 99-113, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37252324

RESUMO

Sileneophioglossa Huan C. Wang & Feng Yang, a new species of Caryophyllaceae, is here described and illustrated based on morphological and molecular evidence. The new species was found in Sichuan and Yunnan provinces, southwest China. Phylogenetic analysis based on ITS sequences showed this new species belongs to section Cucubaloides. Morphologically, it resembles S.phoenicodonta and S.viscidula, which were also found in the southwest China, but clearly differs from the latter two species by having 5-7 mm long calyces with sparsely hirtellous and short glandular hairs, white petals, linear limbs and lobes, and absent or oblong-linear coronal scales. A distribution map and a table with morphological diagnostic characters of new species and its closest relatives are provided, as well as a preliminary conservation assessment of S.ophioglossa under the IUCN criteria.

7.
Am J Bot ; 99(8): 1408-14, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22847538

RESUMO

PREMISE OF THE STUDY: The possible persistence of wild Ginkgo biloba populations in China has long been debated but never scientifically confirmed. We test our hypothesis that the extant Ginkgo populations in the Dalou Mountains (SW China) represent fragments of the original natural Ginkgo range and offer a range of pertinent perspectives on the living fossil Ginkgo's history, prehistory, ecology, and place in human culture-all important aspects of this highly valued species. METHODS: We analyzed the vegetation of the study area, determined the population age structure of Ginkgo, and compared it to existing fossil records. For supporting material, we also examined records of the lack of human presence before the mid-17th century in the area, the local people's beliefs regarding preservation of the forests and existing genetic studies. KEY RESULTS: Current species composition of Ginkgo forests in the Dalou Mountains agrees closely with floristic assemblages from fossil records bearing G. biloba. Current populations are found in habitats similar to those of fossil Ginkgo, which, as today, favored rock crevices. Female to male ratios are 3:2. Estimated ages for many of the trees show that Ginkgo was present in this area prior to human settlement and indigenous peoples of this area are unlikely to have planted Ginkgo because of traditional beliefs. Our results agree with existing genetic studies that show that these mountains were glacial refugia for G. biloba. CONCLUSIONS: The corroborative evidence confirms the finding that these populations represent fragments of the original natural Ginkgo in the valley and lower mountain slopes of the Dalou Mountains.


Assuntos
Ginkgo biloba/genética , Evolução Biológica , China , Ecossistema , Estruturas Genéticas , Genética Populacional , Geografia , Ginkgo biloba/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento , Fatores de Tempo , Árvores
8.
PhytoKeys ; 206: 49-59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761272

RESUMO

Campanulaluzhijiangensis (Campanulaceae: Campanuleae) is described and illustrated as a new species from Yunnan, southwest China. The new species is mainly characterized by its relatively gracile stems polyphyllous, small and oblanceolate leaves, and flowers and fruits with small size within Chinese Campanula. It is only known from a single locality in the valley of the Luzhijiang River, usually occurring in the rock crevices, xerophilous scrubs or grasslands. A table of morphological characters comparing the new species with its closest relatives is provided along with a key to the species of Campanula from Yunnan Province, as well as a preliminary conservation assessment of C.luzhijiangensis under the IUCN criteria.

9.
PhytoKeys ; 199: 9-16, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761874

RESUMO

Indigoferavallicola (Fabaceae), a new species is described and illustrated. This plant is only found from two localities in the central Yunnan Province, southwest China. It is characterized by having the prostrate habit, usually 13-17-foliolate leaves and the relatively small (3-5 mm long) flowers. Morphological comparisons with its closest relatives, I.rigioclada, I.franchetii, I.chaetodonta, and I.henryi are also presented.

10.
PhytoKeys ; 189: 155-162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35210913

RESUMO

Silenevanchingshanensis (Caryophyllaceae), a new species from Fanjingshan Mountain in Guizhou (southwest China) is described and illustrated. It is morphologically similar to S.morrisonmontana and S.hupehensis, from which it can be easily distinguished by having pubescent stems usually 10-15 cm long, linear-oblanceolate leaves 3-6 cm × 3-6 mm, often 2-5-flowered cymes, pink or violet petals and narrowly ovoid capsules.

11.
PhytoKeys ; 206: 75-86, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761271

RESUMO

Breyniahiemalis Huan C. Wang & Feng Yang (Phyllanthaceae), of sect. Cryptogynium (Müll.Arg.) Welzen & Pruesapan in subg. Breynia, is described from Yunnan, south-west China. It is known from only a single locality in the valley of the Yuanjiang River, and usually occurs in the understory of the savanna vegetation. It is characterized by its broadly elliptic to orbicular leaf blades, shallowly plate-like calyces of the staminate flowers, ovaries with clearly erose rim and urceolate capsules. Morphological comparisons with similar species are also presented.

12.
PhytoKeys ; 193: 141-150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586121

RESUMO

Rubusdianchuanensis, a new name for the species previously named as R.vicarius by W. O. Focke in 1911, is proposed. A detailed description, illustrations, and remarks on its phenology, ecology, and geographic distribution are provided. This raspberry (subg. Idaeobatus) is endemic to China and was only found in Sichuan and Yunnan, southwest China. Morphologically, it is most similar to R.ovatisepalus but clearly differs from the latter by having leaf densely white or grey tomentose abaxially, usually leaf-like bracts at the base of inflorescence, 1-6 cm long pedicels, and triangular-ovate sepals with acute to caudate apex.

13.
PhytoKeys ; 194: 95-103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586325

RESUMO

Hemilophiacardiocarpa (Brassicaceae), the sixth species of the Chinese endemic genus Hemilophia, is described and illustrated. This plant is found in the Jiaozishan Mountains in Dongchuan District, northern Yunnan, southwest China. Morphologically, it shows close relationships with H.rockii and H.pulchella, but differs from it in the leaf shape and size, inflorescence, flower size, shape of fruit and length of its pedicel. An updated key to the taxa of Hemilophia is provided.

14.
Plant Divers ; 41(4): 237-249, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31528783

RESUMO

The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained unknown up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are relatively healthier than those in Vietnam.

16.
Nat Commun ; 9(1): 4488, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367062

RESUMO

Today East Asia harbors many "relict" plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions. We further use Ecological Niche Modeling to show that these patterns align with maps of climate refugia, and we predict species' chances of persistence given the future climatic changes expected for East Asia. By 2070, potentially suitable areas with high richness of relict species will decrease, although the areas as a whole will probably expand. We identify areas in southwestern China and northern Vietnam as long-term climatically stable refugia likely to preserve ancient lineages, highlighting areas that could be prioritized for conservation of such species.

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