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1.
In a survey of the karyology of Nonea, which completes an examination of Spanish Boragineae, the chromosome number for N. echioides (L.) Roemer & Shultes is reported for the first time. Relationships between the genera that are included in the tribe Boragineae are discussed, considering chromosomal and morphological characters and the habit of the plants.  相似文献   

2.
ABSTRACT

A new Anchusa species was discovered in the massif of Mt. Lattias in South-Western Sardinia. This species, here described as A. formosa, shows a sharp phenotypic differentiation from the other Sardinian endemic taxa of Anchusa, especially in habit, leaf shape and size, inflorescence and calyx morphology. Ecological traits are also peculiar, the plant being restricted to siliceous debris that accumulates in small depositional areas of dry stream beds. A. formosa is likely to represent a paleogenic schizoendemism originated through isolation and genetic drift from the same genie pool of the other Corso-Sardinian endemic taxa of Anchusa. SEM analyses provide additional information on the micromorphology of the stigma and its papillar pattern, pollen grains, mericarp coat surface and trichomes. The anatomical structure of stem, root and leaf were also analysed. Due to its extreme localization and ecological specialization, A. formosa needs total protection in its natural habitat and should be added to National and International Red Lists of plants at risk of extinction.  相似文献   

3.
    
Aim The presence of numerous reliable fossils and the occurrence of many endemic island species make the Boraginales particularly suitable for integrative biogeographical studies. In this paper we aim to elucidate the time frame and events associated with the origin of selected borages endemic to the Mediterranean climate zone. More specifically, we describe and examine the alternative palaeo‐ and neoendemic hypotheses for their origin. Location Corsica and Sardinia (continental fragment islands) and the Canary Islands (an oceanic island archipelago). Methods Eighty‐nine accessions, representing 30 genera from five families ascribed to the Boraginales, were examined for six chloroplast DNA regions. We used an integrative approach including phylogenetic analyses (Mr Bayes ), Bayesian molecular dating (T3 package) with four fossil constraints on nodes, and biogeographical reconstructions (diva ) to elucidate the temporal and spatial origins of the Corso‐Sardinian and Canary Island endemics. Results Species of Echium endemic to the Canary Islands diverged from their continental sister clade during the Miocene (15.3 ± 5.4 Ma), probably after the rise of the oldest islands (c. 20 Ma). Corso‐Sardinian endemics of Borago diverged from their primarily North African sister clade during the late Miocene‐Pliocene (c. 6.9 ± 3.6 Ma), well after the initial fragmentation of the islands (c. 30 Ma). Similarly, Corso‐Sardinian endemics of Anchusa diverged from the South African Anchusa capensis during the Pliocene–Pleistocene (c. 2.7 ± 2.1 Ma). Main conclusions The present study reveals an Anatolian origin for Anchusa, Borago and Echium and underlines the importance of the Eastern Mediterranean region as a possible reservoir for plant evolution in the Mediterranean Basin. For Anchusa and Borago, the divergence from their respective sister clades on the two types of islands post‐dated the formation of the islands, thus supporting the neo‐endemic hypothesis, whereas the dating results for the origin of Echium endemics were less conclusive.  相似文献   

4.
    
In the framework of the revision of the genus Orobanche (including Phelipaea) in the Mediterranean area, the original material for 31 names of new taxa described from North Africa by Ball, Battandier, Forsskål, Maire (partly with Emberger and Jahandiez), Persoon, Poiret and Pomel has been analysed. Typification is discussed, and where necessary types are designated. Accepted names and synonyms of the recognized taxa are given. Three species are illustrated, and one new combination (O. inexspectata) is proposed.  相似文献   

5.
6.
孟雷  朱相云 《西北植物学报》2006,26(12):2574-2579
在考证了模式标本和查阅了大量腊叶标本的基础上,结合野外居群生物学调查工作,作者对分布于蒙古和我国境内的Glycyrrhiza alaschanicaGrankina、G.gobicaGrankina和G.soongoricaGrankina 3种甘草做了归并处理。认为它们属于乌拉甘草(G.uralensisFisch.ex DC.)的变异类型,均处理为乌拉甘草的异名。  相似文献   

7.
从叶绿体DNA trnL-F序列论双参属的归属问题   总被引:13,自引:0,他引:13  
双参属Triplostegia Wall.ex DC.由分布于东南亚地区的2个种组成,为多年生草本植物。它的归属一直存在争议,有时置于川续断科Dipsacaceae或败酱科Valerianaceae,有时单立一科,即双参科Triplostegiaceae。本研究对广义川续断目Dipsacales s.l.的21种植物(分别来自于败酱科、川续断科、双参属、刺参属Morina、广义忍冬科Caprifoliaceae s. l.、五福花科 Adoxaceae)和外类群人参Panax schin-seng Nees.的叶绿体 DNA trnL-F区进行了测序,并建立系统发育树状图。结果显示,败酱科、川续断科、双参属、刺参属和广义忍冬科的4个属(双盾木属Dipelta、虫胃实属Kolkwitzia、六道木属Abelia和北极花属Linnaea)形成了一个单系群并得到了很强的支持(100% bootstrap);双参属与川续断科有更近的关系,建议作为一个亚科置于川续断科;广义忍冬科为一多系类群;而刺参属与其他广义川续断目类群之间的关系尚不能确定。  相似文献   

8.
    
An annotated synonymic inventory of Italian Selaginella taxa, a practical key for their identification and their dot distribution maps are presented, as a result of our work on the Selaginellaceae account for the Flora Critica d'Italia. The names Lycopodium helveticum L. and Selaginella denticulata var. platystachya Hieron. are typified.  相似文献   

9.
    
I. Camarda 《Plant biosystems》2013,147(3):849-856
Rubus is poorly represented in Sardinia, mainly by the widespread R. ulmifolius and further by two narrow endemic species. Two new species, R. laconensis and R. pignatti, here described and illustrated, grow in two neighbouring small areas of the Sarcidano country. Both are characterized, in particular, by fruits with a low number of large drupelets. R. laconensis is for the time being attributed to the R. caesius aggregate, and R. pignatti to R. subg. Rubus.  相似文献   

10.
在扫描电子显微镜下,对豆科土儿属(Ap ios)和旋花豆属(Coch lianthus)7个种植物的花粉进行了观察.结果表明,2个属的花粉均为三孔沟,形状为三角球形或球形.土儿属的花粉可划分为2种类型:肉色土儿(A.carnea)的花粉外壁为典型的网状纹饰,其它种的花粉外壁较光滑,具颗粒状或短条纹状纹饰,研究结果不支持土儿属下亚属的划分;肉色土儿花粉外壁的网状纹饰式样可能反映了其在土儿属中处在较进化的位置.土儿属东亚分布种的花粉类型较为多样,原始和进化2种类型并存,表明东亚可能是土儿属的起源地和演化中心.旋花豆属的花粉特征和肉色土儿相似,说明两者之间的亲缘关系可能较近.  相似文献   

11.
广义飞蛾藤属(旋花科)花粉形态   总被引:3,自引:0,他引:3  
对广义飞蛾藤属Porana s.l.18个分类群的花粉进行了光学显微镜和扫描电镜观察。除前人报道过的7种1变种外,其余均为首次报道。根据花粉粒的大小、形状、外壁纹饰、沟膜特征,该属花粉可细分为4个类型。研究结果不支持Staples(1993)把该属分为4个独立属的观点,而认为在属内划分为4个亚属较为合理。除毛果飞蛾藤外,花粉形态支持Staples对其它种、变种的归并。从花粉萌发孔类型上看,广义飞蛾藤属在旋花科内应处于较为原始的位置。  相似文献   

12.
广义的紫菀属(Asters.l.)曾是个大包大揽的类群,产于北美和欧亚大陆.Nesom主要根据瘦果的形态和细胞学性状对Asters.l.进行了评价,将北美紫菀类植物从Aster中独立出去,使Aster成为欧亚特有类群.但是,在欧亚各国对Aster有定为一属和分为十多个属等不同的分类学处理,分歧较大.狭义紫菀属(Asters.s.)与从Asters.l.中分出的各属之间的系统学关系,以及后者中某些属与北美紫菀类和紫菀族其他亚族间的系统学关系,都存在很大疑问.过去一直认为北美是Aster的发源地,现在欧亚Asters.l.的起源与演化需要重新研究,而青藏高原是探讨Asters.l.物种多样性形成的关键地区.DNA尤其是DNA序列资料在研究Asters.l.的系统发育和分类上将发挥关键作用.  相似文献   

13.
对栎属青冈亚属17个种及炭栎花粉形态进行扫描电镜观察。结果表明:青冈亚属和炭栎花粉均为三拟孔沟,球形至长球形,(15~28.0)μm×(15.0~25.6)μm。花粉外壁纹饰可划分为3种:(1)蠕虫状(包括皱波状)、(2)聚合颗粒状、(3)棒状或小刺状。各纹饰在组间镶嵌分布。棒状及小刺状纹饰为栎属花粉较为原始式样,并为青冈亚属与高山栎组及部分巴东组(sect.Cerris)共有,推测其间具有较其它栎类更为接近的亲缘关系,可能为广义栎属中较为基础的类群,而与栎亚属sect.Quercuss.s.,Lobatae和Protobalanus关系较远。花粉形态对广义栎属系统分类价值仅适用于较高分类阶元。  相似文献   

14.
    
The geographical distribution of Liliaceae (s. str. ) is analysed on the basis of thefloristic regions proposed by Takhtajan. Some conclusions may be proposed as follows: 1.Liliaceae (s. str. ) consists of nine genera and about 513 species, distributed primarily in the north temperate zone. Statistics shows clearly that the Irano-Turanian Region is most abundant in number of species, The Eastern Asian Region with total nine genera of the family is the diversity centre of Liliaceae (s. str. ). 2. The distribution patterns of the genera may be divided into: 1 ) North temperate distribution pattern: Lloydia, Erythronium, Fritillaria and Lilium; 2) Old world temperate distribution pattern: Gagea and Tulipa; 3) West Asia to Himalayas and Southwest China distribution pattern: Notholirion; 4) East Asia distribution pattern: Cardiocrinum and Nomocharis. 3. The Sino-Himalayas is one of the key regions instudying the evolution of Liliaceae (s. str. ) All nine genera occur in the Eastern Asian Region with most species distributed in Southwest and Northwest China. Chorologically, five genera (Fritillaria, Lilium, Cardiocrinum, Nomocharis and Notholirion) of the Lilieae are overlapped each other in the Sino-Himalayas, showing its diversity centre in this region. The Lilieae is a main stock in the Liliaceae (s. str. ), The genus Nomocharis in this tribe may have been newly differentiated from Lilium in the course of the uplift of Qinghai-Xizang Plateau, a view also supported by Xie Xiao-yang et al.. The place of its origin was considered to be in the southern part of the Hengduan Mountains. 4. The distributions of some species in Liliaceae (s. str. ) seem to be significant for dividing some floristic regions: 1 )Some species of Fritillaria (F. unibracteata Hsiao et K. C. Hsia, F. przewalski Maxim. ex Batal. , F. crassicaulis S. C. Chen, F. cirrhosa D. Don. , F. delavayi Franch. , F. dajinensis S. C. Chen, F. davidii Franch. , F. sinica S. C. Chen and F. sichuanica S. C.Chen) are only distributed in Sino-Himalayan forest subkingdom, while others (F. taiparensis P. Y. Li, F. yuzhongensis S. C. Chen, F. monantha Migo, F. anhuiensis S. C. Chen et S. F. Yin, F. thunbergii Miq. , F. maximowizii Freyn and F. ussuriensis Maxim. ) are restricted to Sino-Japan forest subkingdom. They show a clearly demarcation line between the two subkingdoms, which is identical with what proposed by Wu Cheng-yih. 2) The Eastern Asian Region can be divided into two subkingdoms on the basis of the distribution pattern of the genus Cardiocrinum; C. giganteum (Wall.) Makino and C. gigateum var. yunnanense Leichtlin ex Elwes are restricted to Sino-Himalayan forest subkingdom. C. cathayanum (Wilson) Stearn and C. cordatum (Thunb.) Makino are only found in Sino-Japan forest subkingdom. 3) The distributions of Gagea pauciflora Turcz. , G. triflora(Ledeb.) Roem. et Schult. G. hiensis Pasch, Lloydia tibetica Baker ex Oliver, L. oxycarpa Franch. and L. flavonutans Hara are indicative of a demarcation line between Irano-Turanica Region and Eastern Asian Region. 5. The genus Notholirion occurs in the Eastern Asian Region and Irano-Turanian Region, showing the relationships between the two regions and also between the Chinese flora and Ancient Mediterraneam flora.  相似文献   

15.
    
Abstract

The Italian populations of Koeleria splendens C. Presl, critical group of the Mediterranean flora, are examined from the taxonomic and nomenclatural viewpoints. On the basis of literature data, herbarium investigations and field surveys, many morphologically well-differentiated taxa have been recognized. This group is widespread in the Italian peninsula and Sicily, where it is represented by the following units: K. splendens C. Presl, with four subspecies [subsp. splendens, subsp. grandiflora (Bertol. ex Schultes) Domin, subsp. brutia Brullo, Gangale & Uzunov, and subsp. ophiolitica subsp. nova], K. lucana sp. nova, K. subcaudata (Ascherson & Graebner) Ujhelyi, K. australis Kerner, K. callieri (Domin) Ujhelyi, and K. insubrica sp. nova. As concerns their distribution, both K. splendens and K. lucana are endemic to the Italian territory, while the other species occur also in some eastern Mediterranean countries. The taxonomic position of K. lobata, recently treated by some authors as a synonym of K. splendens, is also examined. A phylogenetic analysis was performed using morphological characters. Finally, a detailed iconography of the main morphological features and an analytical key of the Italian taxa (K. lobata included) are given.  相似文献   

16.
百合科(狭义)植物的分布区对中国植物区系研究的意义   总被引:27,自引:1,他引:27  
本文对百合科(狭义)各属的地理分布作了分析,该科植物集中分布于泛北极域,属于北温带的科。该科所有的9个属,只在东亚区全部有分布,而且该区具有百合科(狭义)植物各系统演化阶段的类群,因此,东亚区是该科的多样化中心。其中百合族所包括的5个属(贝母属、百合属、大百合属、豹子花属和假百合属)集中分布于中国西南至喜马拉雅地区,其分布区均在中国-喜马拉雅地区重叠,表明中国-喜马拉雅地区是百合族的多样化中心。百合族是百合科(狭义)的核心部分。因而认为中国-喜马拉雅地区是研究百合科(狭义)植物演化的关键地区之一。从种类的统计分析表明,伊朗-土兰区分布的种类最多,说明伊朗-土兰区是该科的多度中心.文中还从一些属(贝母属、大百合属、顶冰花属和洼瓣花属)内种的分布,提出可作为划分某些植物区的依据。而且,还从假百合属的分布,阐明中国植物区系与古地中海植物区系的亲缘。  相似文献   

17.
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Leaf epidermis characters in 40 of ca. 250 species of Zanthoxylum (Rutaceae) were investigated using light microscopy (LM) and scanning electron microscopy (SEM). The stomata are anomocytic and exist only on the abaxial epidermis except in Z. nitidum, which also has stomata on the adaxial surface. The epidermal cells are usually polygonal or irregular in shape, with anticlinal walls straight, arched, repand, or sinuous. Under the SEM, the inner margin of the outer stomatal rim is nearly smooth, sinuolate or erose, and the cuticular membrane of the leaf epidermis is smooth, striate, or sometimes striate to wrinkled. These data of leaf epidermis of Zanthoxylum demonstrated that there exist many common characters between subgen. Fagara and subgen. Zanthoxylum, sug-gesting a close relationship between the two subgenera. The utility of some characters in identifying some species of Zanthoxylum was also discussed.  相似文献   

18.
    
An analysis of Italian herbarium specimens belonging to the genus Azolla was carried out using optical microscope and SEM techniques. According to recent international reviews, three micro-morphological characters have been considered for the specimen analysis: (i) number of leaf trichome cells, (ii) septation of glochidia and (iii) features of the macrospore perine. The analysis of the patterns concerning both vegetative and reproductive characters was complicated by the relatively low number of sporulated specimens stored in the Italian Herbaria. The analysis of the selected specimens showed the presence of two well distinct systematic groups. One group was characterized by bicellular leaf trichomes, pluriseptate glochidia and not-warty perine, traits that permitted to taxonomically attribute it to A. cristata. The second group was characterized by monocellular leaf trichomes, non-septate or uniseptate glochidia and warty perine, so that it could be taxonomically attributed to A. filiculoides Lam. This study confirmed the large use in the past of the name ‘A. caroliniana’ to indicate the species actually named A. cristata. In Italy, this species was found to be collected only in the past, while A. filiculoides was found to be present with both ancient and recent herbarium specimens.  相似文献   

19.
The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species ofSolms-laubachia Muschl. (Brassicaceae), have been little studied. Previous molecular studies on the phylogeny of Solms-laubachia showed it to be paraphyletic, leading to considerable expansion not only of its taxonomic limits, but also its geographic range, with the inclusion of taxa from outside the Hengduan region. However, these studies provided little resolution of interspecific relationships, preventing inferences about historical biogeography within the clade. In the present study, new sequence data from two nuclear genes (LEAFY and G3pdh) and two chloroplast intergenic spacers (petN-psbM and psbM-trnD) were combined with existing markers to increase phylogenetic signals. Phaeonychium villosum (Maxim.) Al-Shehbaz was found to be nested within Solms-laubachia s.l. In general, phylogenetic relationships appear to be a good predictor of geography, with the Hengduan Mountain endemics embedded in a paraphyletic grade of species from the western Himalayas and central Asia, but they also imply morphological homoplasy, lncongruence was detected between the nuclear and chloroplast gene trees, perhaps resulting from incomplete lineage sorting of ancestral polymorphisms. The crown age ofSolms-laubachia s.l. was estimated to be approximately 1.42-3.68 mya, using Bayesian relaxed molecular clock analysis. Historical biogeographic analysis using a parametric dispersalextinction-cladogenesis model inferred central Asia and the western Himalayas as most probable ancestral range of Solms-laubachia s.l., and estimated higher rates of eastward expansion than westward during the diversification of descendant lineages. In summary, our results suggest that Solms-laubachia s.l. originated during the Pliocene in central Asia, and subsequently migrated eastward into the Hengduan Mountains, colonizing sky-island, alpine scre  相似文献   

20.
Populations of Phlebotomus major were examined in two endemic and nonendemic foci of visceral leishmaniasis in Iran. Based on the shape of the aedeagus and ventrally located hairs of coxite and pharyngeal armatures, two morphotypes were found sympatrically in the endemic area of Borazjan. Significant differences in morphometric survey were observed in at least 11 measured characters. The aedeagus of the non‐endemic Miyandoab morphotype, and also of a few specimens from Borazjan, is completely parallel throughout its length with a slightly expanded end. Ventrally located hairs of the middle coxite were longer and more compact. It is close morphologically to P. major neglectus (P. neglectus), which was recently recorded from Iran. It is also morphologically similar to P. notus, which has not yet been reported from Iran and needs further investigation. The aedeagus of the morphotype occurring only in Borazjan is narrower in the middle and the hairs are closer to the base of the coxite and are shorter and more outspread, which makes it similar to P. major krimensis or P. neglectus. The two morphotypes occurring sympatrically in Borazjan do not appear to be subspecies and it may be premature to propose them as separate species. Further investigation is needed to clarify the actual status of P. major s. l. in Iran.  相似文献   

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