基于ITS和matK序列的兰科沼兰族分子系统研究及二新种（英文）

沼兰族是兰科植物的大族之一,约2 000种,除了极地和沙漠地区,全球均有分布。该族植物主要分布在热带地区,尤其在东南亚、热带美洲、非洲以及澳大利亚等地区种类非常丰富。目前,已有关于该族植物形态和分子系统的研究,但有关该族亚族和属间的系统关系尚不清楚,属的界定争议也较大。该文基于核基因片段ITS和叶绿体基因片段matK序列,采用最大简约法、最大似然法贝叶斯推理分析法,对现有沼兰族主要属的123种植物和10个外类群植物进行了分子系统学研究。结果表明:沼兰族主要分为3个亚族分支,包括附生的鸢尾兰亚族(Oberoniinae)、地生的羊耳蒜亚族(Liparidinae)和沼兰亚族分支(Crepidiumclade)。鸢尾兰亚族包括6个属、羊耳蒜亚族分支包括5个属、沼兰亚族分支包括4个属;丫瓣兰亚族(Ypsilorchidinae)应归并为鸢尾兰亚族;Disticholiparis属与Stichorkis属的模式标本相同,应并入Stichorkis属;沼兰属(Crepidium)和无耳沼兰属(Dienia)的唇瓣结构差异较大,但二者均为单系类群。此外,在收集野外实验材料过程中,发现了2种产自中国西南部和越南北部的沼兰族新种,分别命名为麻栗坡羊耳蒜(Platystyliparis malipoensis G.D.Tang,X.Y.ZhuangZ.J.Liu)和秉滔羊耳蒜(Cestichis pingtaoi G.D.Tang,X.Y.ZhuangZ.J.Liu)。     

基于ITS和matK序列的兰科沼兰族分子系统研究及二新种

沼兰族是兰科植物的大族之一,约2000种,除了极地和沙漠地区,全球均有分布.该族植物主要分布在热带地区,尤其在东南亚、热带美洲、非洲以及澳大利亚等地区种类非常丰富.目前,已有关于该族植物形态和分子系统的研究,但有关该族亚族和属间的系统关系尚不清楚,属的界定争议也较大.该文基于核基因片段 ITS 和叶绿体基因片段 mat K 序列,采用最大简约法、最大似然法贝叶斯推理分析法,对现有沼兰族主要属的123种植物和10个外类群植物进行了分子系统学研究.结果表明：沼兰族主要分为3个亚族分支,包括附生的鸢尾兰亚族(Oberoniinae)、地生的羊耳蒜亚族(Liparidinae)和沼兰亚族分支(Crepidium clade).鸢尾兰亚族包括6个属、羊耳蒜亚族分支包括5个属、沼兰亚族分支包括4个属;丫瓣兰亚族(Ypsilorchidinae)应归并为鸢尾兰亚族;Disticholiparis 属与 Stichorkis 属的模式标本相同,应并入 Stichorkis 属;沼兰属(Cre-pidium )和无耳沼兰属(Dienia )的唇瓣结构差异较大,但二者均为单系类群.此外,在收集野外实验材料过程中,发现了2种产自中国西南部和越南北部的沼兰族新种,分别命名为麻栗坡羊耳蒜(Platystyliparis mali-poensis G．D．Tang,X．Y．Zhuang & Z．J．Liu)和秉滔羊耳蒜(Cestichis pingtaoi G．D．Tang,X．Y．Zhuang &Z．J．Liu).     

菜粉蝶对两种迁地保护的兰科植物传粉和繁殖成功的作用

迁地保护是防止物种灭绝的有效措施。为了解在新栖息地兰科植物与昆虫之间的关系, 从而为兰科植物的保护提供借鉴, 作者对迁地栽培于深圳市全国兰科植物种质资源保护中心的本地种血叶兰(Ludisia discolor)和外来种银带虾脊兰(Calanthe argenteo-striata)的传粉系统和繁殖策略进行了观察和研究。血叶兰和银带虾脊兰都具有白色小花组成的花序, 且花有距。在开放栽培条件下, 菜粉蝶(Pieris rapae)是这两种兰科植物唯一有效的传粉者。菜粉蝶携带血叶兰和银带虾脊兰花粉块的部位分别是降落时平衡身体的左侧足部和取食花蜜的喙。两种兰科植物传粉效率较高, 花粉移走与沉降的比值分别为1.14 : 1和0.74 : 1。血叶兰的结实率在2007和2008两年间无显著差异, 且均高于银带虾脊兰。究其原因, 一方面是由于它为传粉者提供报酬; 另一方面是因为血叶兰的花期与菜粉蝶的盛发期相吻合, 有利于充分利用传粉者; 而银带虾脊兰的花期滞后于菜粉蝶的盛发期, 传粉者缺失使得部分花未能授粉。血叶兰和银带虾脊兰都是高度自交亲和的物种, 但不存在无融合生殖和自动自花授粉的现象; 自交和异交的繁殖成功率无显著差异。这两种兰科植物可能存在由传粉者导致的自交现象。血叶兰和银带虾脊兰在迁地栽培到兰科中心后生长良好, 每年花期都有自然结果的现象, 植株周围有新生幼苗的建立, 种群有逐渐扩大的趋势, 显示出迁地保护的可行性。可以预测若干年后, 这两个种在兰科中心具有建立稳定种群的可能性。     

兰科雄蕊发育多样性研究进展

兰科是被子植物中多样性最丰富的家族,其雄蕊形态和功能分化在亚科间变化明显,是该物种多样性形成及适应性传粉生物学的研究重点。基于现有研究资料,该文初步归纳了兰科雄蕊发育多样性的主要研究内容及现状,为野生兰花资源的保护与利用提供科学依据。结果如下:(1)可育雄蕊数目的减少和花粉愈合程度的增加在兰科分子系统树上呈明显的平行演化趋势。(2)兰科雄蕊数目的减少和功能分化与早期花器官发生中存在大量的滞后和缺失、次生融合与分裂现象等密切相关。(3)花药开裂时的4类散粉单元的花粉超微形态特征在亚科、族、亚族、属和种间差异明显。(4)兰科花药散粉单元可以为单花粉粒,也可以通过花药发育过程中源自绒毡层的三类黏性物质而聚合成不同的散粉单元,包括花粉鞘、弹性黏素和其他黏性物质。(5)花药发育揭示了兰亚科的花粉小块结构主要有三类(红门兰型、树兰型和过渡型),树兰亚科的不同数目(2、4、8)和形态(全缘、浅裂、深裂、孔裂)的花粉团是由于花药原基分化出的不育隔膜组织的数目、朝向和位置而形成的。(6)兰科花药发育中,花药室数目、花药壁发育类型、绒毡层细胞核数目、不育隔膜组织分化、胞质分裂类型、小孢子四分体排列形式、花粉细胞核数目等在亚科和属间差异明显。然而,由于种类繁多,现有研究资料难以为理解兰科雄蕊发育提供清晰的线索,包括雄蕊的发育模式、散粉单元的形成机制、花药发育的胚胎学特征等。因此,有必要重视兰科雄蕊发育研究,包括扩大取样范围和利用多学科技术方法和修订兰科花形态常用术语等。     

广西雅长自然保护区兰科植物多样性研究

对广西雅长兰科植物自然保护区的兰科植物多样性进行调查研究。该保护区兰科植物多样性具有如下特点:(1)物种多样性丰富,居群数量大,共有兰科植物44属113种(含5变种);(2)分布广泛,生境复杂多样;(3)地理成分兼备热带和亚热带性质,生活类型齐全;(4)垂直分布格局呈现一定规律性。文章最后提出了该保护区兰科植物多样性保护及利用的初步建议。     

兰科植物欺骗性传粉

植物与传粉动物的互利关系在生态系统中非常普遍。然而,有许多植物不为传粉者提供任何报酬,而是利用各种欺骗方式诱骗昆虫拜访,从而实现传粉,即欺骗性传粉。兰科是被子植物大科之一,其高度特化的繁殖器官和适应于昆虫传粉的精巧结构令人称奇。进化论创始人达尔文描述了许多兰花与昆虫精巧的传粉系统,但他忽视了欺骗性传粉的存在。事实上,近1/3的兰科植物都依赖于欺骗性传粉。欺骗性传粉可能是导致兰科植物多样性的重要原因之一。兰花利用或操作昆虫觅食、交配、产卵和栖息等行为,演化出各种各样的欺骗性传粉机制,常见的类型包括泛化的食源性欺骗、Batesian拟态、性欺骗、产卵地拟态和栖息地拟态。花的颜色、形态和气味在欺骗性传粉的成功实现中起到了重要作用。欺骗性兰花与传粉昆虫之间的演化可能是不同步的,兰花追踪昆虫的行为信号而发生分化,然而欺骗性传粉可能对昆虫造成一定的伤害,从而对昆虫也施加选择压力。由于昆虫的学习行为,欺骗性的兰花一般具有低的昆虫拜访率和结实率,其繁殖成功率受各种因素的影响。欺骗性加剧了兰花对传粉昆虫的依赖,使其具有更高的灭绝风险,传粉生物学的研究能为兰科植物的有效保护提供指导。在欺骗性传粉系统中,有报酬的伴生植物、拟态模型和其他拟态信号提供者对传粉成功有重要影响。因此,研究欺骗性传粉兰花、传粉昆虫和相关的生物和生态因子的网状进化关系具有重要理论和实践意义。     

中国曲唇后兰属的订正

曲唇兰属(Panisea)为兰科贝母兰亚族(Coelogyninac)的一个小属,全世界只有9种,主要分布于自喜马拉雅地区至印度支那。我国长期只记载1个种,即产于贵州的曲唇兰(P.cavaleriei Schltr.)。但在中国高等植物图鉴中,首次报告云南产另一个种P.bia(Kerr)Tang et Wang。作者在整理该属并结合在英国邱皇家植物园标本馆看到     

湖北兰科植物多样性及其区系地理特征

湖北植被尤其是鄂西地区,在近代以来备受植物学家的关注。该研究基于植物标本、文献资料与野外调查成果,整理出湖北兰科植物名录,结合湖北的地形与气候特征分析了湖北兰科植物的分布格局、区系及多样性特征。结果表明:湖北兰科植物主要分布在西南、西北、东北及东南部山区,以鄂西山地最为丰富,中南部江汉平原最少,900~1 200 m中海拔地段丰富度最高;物种多样性由南至北、由西至东呈递减趋势,鄂西南与鄂西北之间具有最大相似性;除拟兰亚科(subfam.Apostasioideae)外的5个亚科湖北均有分布,计有15族54属141种,单种属和寡种属分别占总属数的50.00%和33.33%;湖北兰科植物东亚分布成分占40.43%,中国特有种占总种数的41.84%,东亚区系主体突出,中国特有成分所占比例较大,其中中国—日本成分占优势;温带属性较强,亚热带向温带过渡特征明显,有25个热带分布属及27个温带分布属,热温比为0.93,种级水平的热带分布类型占8.51%,温带分布类型占91.49%;一些稀缺种在台湾与湖北的间断分布,表明两者植物区系有较强的关联性;湖北兰科植物区系与西南及横断山区联系密切,是与东部地区植物区系交流的中转站。     

怒江河谷低海拔地区残存原生植被中兰科植物多样性

为了解怒江河谷低海拔地区的生物多样性,我们以兰科植物为例,对怒江河谷贡山和福贡段海拔1,600m以下的4片残留原生植被中的兰科植物多样性和受威胁状况进行了调查.通过4次野外路线法考察和相关的室内标本研究,发现这些残存的森林中兰科植物多样性非常丰富,目前已记录33个属60种兰科植物,其中附生兰为42种,地生兰为18种.在己鉴定的物种中,一种毛兰属植物(Eria sp.)为中国新记录种或新种,疣花三角兰(Trias verrucosa)为怒江河谷特有,洛氏羊耳蒜(Liparis rockii)为怒江河谷和独龙江河谷所特有,杓兰属一种(Cypripedium sp.)、盆距兰(Gastrochilus calceolaris)、羽唇兰(Ornitochilus difformis)、带叶兰(TaeniophyHum glandulosum)、匙萼卷瓣兰(Bulbophyllum spathulatum),短穗竹茎兰(Tropidia curculigoides),卵叶火烧兰(Epipactisroyleana)等为本区域新记录种.这些兰科植物面临的主要威胁为生境破碎化、生境质量下降和生境丧失.我们建议尽快开展该地区生物多样性调查和濒危状况评估,并制定和实施有效的保护措施.     

花舞者——扇脉杓兰

<正>杓兰属植物是兰科(Orchidaceae)杓兰亚科(Cypripedioideae)的一个保育研究的热点类群,全属植物约50种(含变种),中国是该属植物的分布中心,我国产32种、1变种,其中24种为特有种[1]。扇脉杓兰(Cypripedium japonicum)是一种珍稀的多年生地生兰,隶属于兰科(Orchidaceae)杓兰亚科(Cypripedioideae)杓兰属(Cypripedium),具极高观赏价值。扇脉杓兰中药名为扇子七,全株可入药,《陕西中草药志》记有:扇     

高黎贡山兰花的多样性

对高黎贡山兰科植物的生物地理学和多样性进行了研究。1.兰科是高黎贡山种子植物中最大的科,包括75属265种。2.高黎贡山兰花起源于新、旧世界的热带和温带, 热带属占60%(45属),温带属占38.67%(29属),包括2个云南特有属。但是,高黎贡山兰科植物与地中海地区和中亚地区的联系十分微弱。3.高黎贡山的兰花以地生兰为主。这里,57.33%(43属)为地生兰,而附生兰和腐生兰仅分别为31属和3属。4.兰花物种的分布区式样表明高黎贡山兰花以温带兰为主 温带兰占总种数的69.43%(184种),包括东亚成分即滇西高黎贡山-东喜马拉雅分布的种和中国西南部特有种,它们是高黎贡山兰花区系的核心。5.高黎贡山兰科的特有现象在于1)具有云南二个特有属蜂腰兰Bulleyia和反唇兰Smithorchis;2)有高黎贡山特有种21个,如泸水兜兰Paphiopedilum markianum,贡山风兰Cymbidium gongshanense,贡山贝母兰Coelogyne gongshanense,热带附生兰——万带兰亚科在高黎贡山没有形成特有种;3)高黎贡山北段的特有种比南段丰富贡山有14种,腾冲仅有4种; 海拔1800～2100 m的梯度带特有种最多(13种);4)高黎贡山有云南特有种10种,其中小花槽舌兰Holcoglossum junceum是一个热带种,因为板块位移而来到了亚热带地域;5)高黎贡山的兰科植物中有19.25%(51种)是中国特有种,它们出现在高黎贡山,分布在云南其他地区和西南的一些省区。高黎贡山特有种,分布到高黎贡山的云南特有种和分布到高黎贡山的中国特有种一共为82种,占高黎贡山兰科总种数的30.91%, 兰科在高黎贡山是一个特有化程度很高的类群。     

An examination of nectar production in 34 species of Dendrobium indicates that deceptive pollination in the orchids is not popular

Nectar, the most common floral reward, is generally used to determine whether an orchid species involves deceptive pollination. Estimates of the deceptive pollination systems with nectarless flowers have ranged from one quarter to one third of the nearly 30 000 species of orchids. These estimates, however, are biased towards temperate-zone, usually terrestrial, orchids. Here we investigated nectar production and property in 34 epiphytic orchid species of the Southeast Asian genus Dendrobium. Twenty-one species were observed producing nectar. The amount and sugar concentration (in bagged flowers) of 12 species varied from 0.45 to 2.78 μL and from 8.1% to 31.1%. The nectar was sucrose-dominant, typical of bee-pollinated flowers. Reconstruction of phylogenetic relationship indicated that transition of nectar secretion occurred in the genus. Spur length was positively correlated with flower size but species with relatively long spurs tended to produce small volume of nectar. Nectar production was strikingly variable among and within individuals in some species, suggesting that a vital measurement of bagged and fresh flowers is needed. Given that the quantitative measurement of nectar or floral reward in orchid species remains scarce, an estimate of deceptive pollination systems awaits further survey in diverse genera.     

Orchid pollination by sexual deception: pollinator perspectives

The extraordinary taxonomic and morphological diversity of orchids is accompanied by a remarkable range of pollinators and pollination systems. Sexually deceptive orchids are adapted to attract specific male insects that are fooled into attempting to mate with orchid flowers and inadvertently acting as pollinators. This review summarises current knowledge, explores new hypotheses in the literature, and introduces some new approaches to understanding sexual deception from the perspective of the duped pollinator. Four main topics are addressed: (1) global patterns in sexual deception, (2) pollinator identities, mating systems and behaviours, (3) pollinator perception of orchid deceptive signals, and (4) the evolutionary implications of pollinator responses to orchid deception, including potential costs imposed on pollinators by orchids. A global list of known and putative sexually deceptive orchids and their pollinators is provided and methods for incorporating pollinator perspectives into sexual deception research are provided and reviewed. At present, almost all known sexually deceptive orchid taxa are from Australia or Europe. A few sexually deceptive species and genera are reported for New Zealand and South Africa. In Central and Southern America, Asia, and the Pacific many more species are likely to be identified in the future. Despite the great diversity of sexually deceptive orchid genera in Australia, pollination rates reported in the literature are similar between Australian and European species. The typical pollinator of a sexually deceptive orchid is a male insect of a species that is polygynous, monandrous, haplodiploid, and solitary rather than social. Insect behaviours involved in the pollination of sexually deceptive orchids include pre‐copulatory gripping of flowers, brief entrapment, mating, and very rarely, ejaculation. Pollinator behaviour varies within and among pollinator species. Deception involving orchid mimicry of insect scent signals is becoming well understood for some species, but visual and tactile signals such as colour, shape, and texture remain neglected. Experimental manipulations that test for function, multi‐signal interactions, and pollinator perception of these signals are required. Furthermore, other forms of deception such as exploitation of pollinator sensory biases or mating preferences merit more comprehensive investigation. Application of molecular techniques adapted from model plants and animals is likely to deliver new insights into orchid signalling, and pollinator perception and behaviour. There is little current evidence that sexual deception drives any species‐level selection on pollinators. Pollinators do learn to avoid deceptive orchids and their locations, but this is not necessarily a response specific to orchids. Even in systems where evidence suggests that orchids do interfere with pollinator mating opportunities, considerable further research is required to determine whether this is sufficient to impose selection on pollinators or generate antagonistic coevolution or an arms race between orchids and their pollinators. Botanists, taxonomists and chemical ecologists have made remarkable progress in the study of deceptive orchid pollination. Further complementary investigations from entomology and behavioural ecology perspectives should prove fascinating and engender a more complete understanding of the evolution and maintenance of such enigmatic plant‐animal interactions.     

A narrow group of monophyletic Tulasnella (Tulasnellaceae) symbiont lineages are associated with multiple species of Chiloglottis (Orchidaceae): Implications for orchid diversity

? Premise of the study: The Orchidaceae is characterized by exceptional species diversity. Obligate orchid mycorrhizae are predicted to determine orchid distributions, and highly specific relationships between orchids and fungi may drive orchid diversification. In this study, mycorrhizal diversity was examined in the terrestrial, photosynthetic orchid genus Chiloglottis to test the hypothesis of mycorrhizal-mediated diversification in the genus Chiloglottis. This orchid genus secures pollination by sexual deception, an obligate and highly specific pollination strategy. Here we asked whether the obligate orchid-fungal interactions are also specific. ? Methods: Two sequenced loci, the internal transcribed spacer region (ITS) and mitochondrial large subunit (mtLSU), were used to identify fungal isolates and assess fungal species diversity. Symbiotic germination of two species Chiloglottis aff. jeanesii and C. valida were used to assess germination potential of isolates and confirm mycorrhizal association. ? Key results: Phylogenetic analyses revealed that six representative Chiloglottis species spanning a broad survey of the genus were all associated with a narrow group of monophyletic Tulasnella fungal lineages. ? Conclusions: The Chiloglottis-Tulasnella interaction appears to be the first known case of such a narrow symbiont association across a broadly surveyed orchid genus. It appears that the specific pollination system of Chiloglottis, rather than specific orchid-fungal interactions has been the key driving force in the diversification of the genus. These findings also indicate that plant groups with highly specific mycorrhizal partners can have a widespread distribution.     

Genome size variation in Orchidaceae subfamily Apostasioideae: filling the phylogenetic gap

With more than 160‐fold variation, Orchidaceae are currently the most diverse angiosperm family with respect to the amount of nuclear DNA. This study provides first genome size estimates for approximately 50% of species currently recognized in subfamily Apostasioideae, which is sister to the other four orchid subfamilies. The estimated 1C‐values range from 0.38 pg in Apostasia nuda to 5.96 pg in Neuwiedia zollingeri var. javanica, a nearly 16‐fold range. The two genera show non‐overlapping genome sizes, with those in Apostasia being distinctly smaller than those in Neuwiedia. In fact, most Apostasia spp. are at the lower end of the range of orchid C‐values. Observed discontinuities in DNA amounts in genera most probably reflect interspecific variation in ploidy. In addition to ploidy heterogeneity in N. zollingeri var. javanica, intraspecific variation in genome size (up to 17.7%) was also detected in some species; this can be plausibly related to the incidence of different geographical variants or unrecognized taxonomic heterogeneity. The AT content varied from 62.6 to 66.0%, which is in the upper range recorded for angiosperms. The genome size data obtained in this study fill a major phylogenetic gap in Orchidaceae and show that (very) small genomes prevail in subfamily Apostasioideae. © 2013 The Linnean Society of London     

Speciation in the Orchidaceae: confronting the challenges

The Orchidaceae is renowned for its large number of species (19,500) and its many diverse, even bizarre, specialized pollination systems. One unusual feature of orchids is the high frequency of food deception whereby animal pollination is achieved without providing nectar, pollen or other food rewards. Food-deceptive pollination is estimated to occur in approximately one-third of all orchids. Equally intriguing is pollination by sexual deception whereby pollination is achieved by the sexual attraction of male insects to the orchid flower. Sexual deception is found in several hundred species representing multiple lineages. Given their rich species diversity and extraordinary plant-animal interactions, orchids clearly offer exciting research opportunities in pollination biology, reproductive isolation and speciation, yet surprisingly they remain under-represented in scientific investigations both in these fields and more generally. In this special issue of Molecular Ecology, Moccia et al. provide an exemplar study that combine multiple lines of evidence to illuminate the mechanism of reproductive isolation between two closely related food-deceptive orchids. Their study demonstrates that many of the challenges that confront orchid researchers and impede progress in our understanding of speciation in the Orchidaceae can be overcome by the creative application and integration of both old and new tools in ecology and genetics.     

Epiphytism and pollinator specialization: drivers for orchid diversity?

Epiphytes are a characteristic component of tropical rainforests. Out of the 25,000 orchid species currently known to science, more than 70% live in tree canopies. Understanding when and how these orchids diversified is vital to understanding the history of epiphytic biomes. We investigated whether orchids managed to radiate so explosively owing to their predominantly epiphytic habit and/or their specialized pollinator systems by testing these hypotheses from a statistical and phylogenetic standpoint. For the first approach, species numbers of 100 randomly chosen epiphytic and terrestrial genera were compared. Furthermore, the mean number of pollinators per orchid species within the five subfamilies was calculated and correlated with their time of diversification and species richness. In the second approach, molecular epiphytic orchid phylogenies were screened for clades with specific suites of epiphytic adaptations. Epiphytic genera were found to be significantly richer in species than terrestrial genera both for orchids and non-orchids. No evidence was found for a positive association between pollinator specialization and orchid species richness. Repeated associations between a small body size, short life cycle and specialized clinging roots of twig epiphytes in Bulbophyllinae and Oncidiinae were discovered. The development of twig epiphytism in the first group seems repeatedly correlated with speciation bursts.     

Orchid conservation in China from 2000 to 2020: Achievements and perspectives

We review achievements in the conservation of orchid diversity in China over the last 21 years. We provide updated information on orchid biodiversity and suggestions for orchid conservation in China. We outline national policies of biodiversity conservation, especially of orchid conservation, which provide general guidelines for orchid conservation in China. There are now approximately 1708 known species of Orchidaceae in 181 genera in China, including five new genera and 365 new species described over the last 21 years. The assessment of risk of extinction of all 1502 known native orchid species in China in 2013 indicated that 653 species were identified as threatened, 132 species were treated as data-deficient, and four species endemic to China were classified as extinct. Approximately 1100 species (ca. 65%) are protected in national nature reserves, and another ~66 species in provincial nature reserves. About 800 native orchid species have living collections in major botanical gardens. The pollination biology of 74 native orchid species and the genetic diversity and spatial genetic structure of 29 orchid species have been investigated at a local scale and/or across species distributions. The mycorrhizal fungal community composition has been investigated in many genera, such as Bletilla, Coelogyne, Cymbidium, Cypripedium, and Dendrobium. Approximately 292 species will be included in the list of national key protected wild plants this year. Two major tasks for near future include in situ conservation and monitoring population dynamics of endangered species.     

Orchid diversity: an evolutionary consequence of deception?

The Orchidaceae are one of the most species-rich plant families and their floral diversity and pollination biology have long intrigued evolutionary biologists. About one-third of the estimated 18,500 species are thought to be pollinated by deceit. To date, the focus has been on how such pollination evolved, how the different types of deception work, and how it is maintained, but little progress has been made in understanding its evolutionary consequences. To address this issue, we discuss here how deception affects orchid mating systems, the evolution of reproductive isolation, speciation processes and neutral genetic divergence among species. We argue that pollination by deceit is one of the keys to orchid floral and species diversity. A better understanding of its evolutionary consequences could help evolutionary biologists to unravel the reasons for the evolutionary success of orchids.