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A distinctive new species of dwarf monocaulous Coffea (Rubiaceae) from Cameroon is described and illustrated. Coffea mapiana is the second dwarf monocaulous known from Cameroon. Its diagnostic characters are elucidated and its taxonomic affinities are discussed; a conservation assessment is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 425–430.  相似文献   

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Mantalania longipedunculata De Block & A.P. Davis, a new species of Rubiaceae (Gardenieae) from Île Sainte Marie, Madagascar, is described, illustrated, and compared with the three other species in the genus. An extinction risk assessment is given, using the categories and criteria of the World Conservation Union (IUCN).  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 421–424.  相似文献   

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解焱 《生物多样性》2022,30(10):22445-3254
IUCN受威胁物种红色名录已经成为世界上最全面的关于全球动物、真菌和植物物种灭绝风险状况的信息来源, 是生物多样性健康的关键指标, 是促进生物多样性保护和决策的有力工具。本文全面介绍IUCN受威胁物种红色名录(简称IUCN红色名录)的发展以及应用状况, 积极推动其在中国的物种评估和广泛应用。总结了IUCN红色名录从依赖于评估专家的主观意志决定物种濒危等级的濒危物种红皮书(Red Data Book)到IUCN受威胁物种等级和标准(3.1版)的客观量化和所有门类使用统一标准的过程。该等级体系可囊括全球所有物种, 其中“受威胁”的3个等级——极危(CR)、濒危(EN)或易危(VU)需使用5个标准进行量化评估, 对评估规范有非常严格的要求。该等级和标准体系不仅适用于全球层面, 同样也适用于地区层面物种评估, 只是在具体物种种群如果和周边其他地区(国家)存在种群交流情况时, 评估结果要进行调整。迄今为止, 全球层面使用该等级体系和标准评估了14万多种(其中在中国有分布的物种10,846种), 100多个国家和地方制定了地区/国家层面的红色名录, 中国红色名录评估了5.5万多种。IUCN红色名录已广泛应用于评估生物多样性变化速度; 为保护规划提供决策信息; 支持履行国际公约、修订国家/地区重点保护物种名录和自然保护地管理等; 指导资源有效合理分配和宣传教育等。广泛应用过程中, 讨论主要集中在获取数据的方法改进上; 另外, 一方面有专家认为标准存在缺陷需要完善, 另一方面有呼吁维持标准的长期相对稳定, 以便进行跨时间、跨区域、跨物种门类的比较。本文提出来了中国红色名录的持续机制和应用建议, 包括建立中国红色名录委员会、建立中国红色名录专业网站、发展评估专家队伍、建立中国红色名录评估更新机制, 以及加强国际协作、促进全球和中国红色名录的应用和发展。  相似文献   

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The taxonomy of the desert shrub genus Fagonia is revised in detail. In total 167 names are accounted for, lectotypes are selected for 33 names, and two names are neotypified. A key to the 34 species is presented, as well as distribution maps for each species. Three new species are described and illustrated, F. densispina and F. latistipulata from Somalia, and F. hadramautica from Yemen. Of the accepted species, 24 are restricted to the Old World and eight to the New World. Most of the Old World species are confined to the Saharo‐Sindian region, with two extending to parts of Macaronesia. Eight species are endemic to the Somali‐Masai region, and two are restricted to southern Africa. In the New World four species are endemic to Baja California, two to northern Baja California and adjacent parts of southwestern USA, one to the province of Coahuila in northeastern Mexico, and one to Chile and Peru. The names of all four species of Fagonia currently on the IUCN Red List of Threatened Plants are put into synonymy.  相似文献   

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中国实蕨属的分类修订   总被引:2,自引:0,他引:2  
对实蕨属Bolbitis的17种植物的孢子进行了扫描电镜观察。根据孢子周壁特征,中国产实蕨属的孢子明显可分为3种类型:A型孢子具网状周壁,B型孢子具鸡冠状-波状周壁,C型孢子具平滑的波状周壁。孢子周壁特征、叶脉式样和叶片顶部的形态是实蕨属中最有价值的分类学性状。根据标本检查,结合野外调查和孢子形态观察,对中国产实蕨属的分类进行了修订,确定中国有实蕨属植物20种和3杂交种,其中包括2个新组合B. fengiana (Ching) S. Y. Dong和B. medogensis (Ching &; S. K. Wu) S. Y. Dong,以及2个中国新分布B. costata Ching ex C. Chr.和B. hookeriana K. Iwats.。将B. latipinna Ching、B. media Ching &; Chu H. Wang、B. yunnanensis Ching、Egenolfia crassifolia Ching、E. crenata Ching &; P. S. Chiu、E. fengiana Ching、E. medogensis Ching &; S. K. Wu和E. ×yunnanensis Ching &; P. S. Chiu等8个名称处理为新异名。文中给出了分种检索表、每个种的生境和分布资料、大多数种的特征集要和孢子扫描电镜照片。  相似文献   

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De Silva et al . (2007) present an overview of the distribution and conservation status of the endemic freshwater fish of Asia. Within that review they use data from the IUCN Red List of Threatened Species™ (2006) to conduct an analysis of the conservation status of those endemic fish species. Their analysis is incorrect and provides a very misleading impression of the level of threat to Asian freshwater fish and to freshwater fish at the global scale. The errors stem from a misinterpretation of the data presented on the IUCN Red List. The sources of errors are discussed below and the opportunity is taken to clarify what the information on the IUCN Red List represents.  相似文献   

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Conservation status, identification, distribution, abundance, habitat and ecology, threats, conservation actions and recommendations of an endemic catfish, King’s bullhead, Silurus mento were introduced.  相似文献   

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Trinidad and Tobago are home to three endemic species in the anuran genus Pristimantis, of which two (Pristimantis charlottevillensis and Pristimantis turpinorum) occur in Tobago alone and the third (Pristimantis urichi) is present on both islands. Earlier, the IUCN assessed the conservation status of these species as: P. urichi, Endangered (EN); P. charlottevillensis, Least Concern (LC); P. turpinorum, Vulnerable (VU). However, these assessments were based on very little field-based evidence. Here, we present survey results which contributed to reassessments as LC, VU and Data Deficient for these three species, respectively. Despite the close proximity of Trinidad to northern Venezuela, the islands do not share any Pristimantis species with the mainland, which holds a rich endemicity of Pristimantis regionally. In this study, we used genetic sequencing from several island populations and compared them to northern Venezuelan endemics to assess genetic divergence for the first time. The time tree analyses found that only the northern Tobago species P. turpinorum is closely related to mainland Pristimantis, with a genetic split dating to the Late Miocene, suggesting a vicariant event of mainland and island species. Pristimantis urichi, although identical between the two islands, remains highly divergent from the mainland species. Similar results were found for P. charlottevillensis. In addition, there was a high level of divergence between P. urichi and P. charlottevillensis. These findings indicate different island colonization events by different lineages. Sequencing other Venezuelan species remains pivotal to unravel the complexity of the colonization episodes in the region, likely influenced by the changing topography and multiple connection and isolation episodes of the islands by eustatic sea-level changes.  相似文献   

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The Sungazer (Smaug giganteus) is a threatened lizard species endemic to the Highveld grasslands of South Africa. The species faces risks from habitat loss and fragmentation, and illegal harvesting for traditional medicine and the pet trade. Despite these threats, the current conservation status of the species was poorly validated. We visited 79 Sungazer populations recorded in 1978 to assess population change since the initial surveys, and surveyed an additional 164 sites to better define the distribution and estimate the current population size. We interrogated all known historical trade data of the species. One-third of Sungazer populations have been extirpated over the past 37 years. The distribution includes two allopatric populations, with the smaller Mpumalanga population experiencing a significantly higher decline. The species has an extent of occurrence (EOO) of 34 500 km2, and an area of occupancy (AOO) of 1149 km2. The interpreted distribution is 17 978 km2, and just under 60% remains untransformed grassland. We estimate a population size of 677 000 mature individuals, down 48% from the estimated historical population, prior to commercial agricultural development. A total of 1194 live Sungazers were exported under permit from South Africa between 1985 and 2014, with a significant increase in numbers exported over the last decade. Without any evidence of captive breeding, we believe that these animals are all wild-caught. Based on the AOO, level of decline, fragmentation within the distribution and suspected level of exploitation, we recommend classification of the species as Vulnerable under IUCN Red List Criteria A2acd and B2ab(ii–v). The establishment of a protected area network, genetic research and further investigations into the pet and traditional medicine trades are urgently needed.  相似文献   

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The four related genera: Ainsworthia Boiss., Tordylium L., Synelcosciadium Boiss. and Mandenovia Alava are revised. Data are presented from detailed gross morphology, mericarp surface features and anatomy, and palynology.
The results show: (1) Ainsmorthia and Synelcosciadium are congeneric with the genus Tordylium, and that Mandenovia is a good monotypic genus; (2) Tordylium persicum is synonymous with 7. cappadocicum and 7. aegaeum with 7. pestalozzae; (3) the genus Tordylium is best divided into subgenus Tordylium (including Synelcosciadium) and subgenus Ainsworthia (Boiss.) Drude. The latter is divided into section Condylocarpus (Hoffm.) DC, section Hasselquistia (L.) Boiss. and section Univittata Drude.
A new species of Tordylium is described, and two new combinations made. A taxonomic treatment of the genus 'Tordylium', together with a key to the species, is given.  相似文献   

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Tetsuo Koyama 《Brittonia》1984,36(2):184-205
Heterosmilax, a small southeastern Asiatic genus in the Smilacaceae, comprises 11 species in two sections, includingH. micrandra, which is described as new from Hainan, China. These taxa are taxonomically discussed, described, illustrated, and a key is provided to differentiate them.  相似文献   

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On oceanic islands, the evolution of plants and animals with particular characteristics is favoured due to their isolation, populations normally comprising a large number of unique, endemic species. The Madeira and Selvagens archipelagos are considered biodiversity hotspots, containing an especially rich bryoflora. Due to its characteristically small size, this taxonomic group does not get much attention in conservation programmes. However, these plants are an important component of terrestrial ecosystems, representing a major part of biodiversity and playing a vital role in the ecosystem's functioning. As such, the development of the first Red List for Madeira and Selvagens Archipelagos has the potential to guide conservation efforts focused on taxa and habitats where threatened species and endemics are better represented. By applying the International Union for Conservation of Nature and Natural Resources (IUCN) criteria, recently revised to apply to small islands, it was possible to obtain the percentage of threatened taxa present in the archipelagos (23.6%), and for each habitat type. It was verified that high mountain habitats and the Laurel forest represent areas that host higher percentages of threatened taxa (29.5% and 22.2%). An important result of the present Red List is the identification of hotspots for bryophyte diversity, supporting the definition of reserves/microreserves. The information obtained can also be linked up with the Red Lists of other taxonomic groups to work towards the definition of a more holistic conservation strategy.  相似文献   

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In connection with a revision of Gerbera L. nom. cons. in Africa the genus Perdicium L. is revised. The genus includes two species, P. capense L. and P. leiocarpum DC. in the Western Cape Region of South Africa.  相似文献   

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