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Morphological and plastid rbcL and trnG-R sequence data suggest that the fern currently recognized as Megalastrum lasiernos (Dryopteridaceae) is in fact a tree fern (Cyatheaceae) and a member of the Cyathea clade. Accordingly, a new combination is made: Cyathea myriotricha. Based on morphological and ecological similarities, this species appears most closely related to C. aterrima. Both species are described and illustrated herein.  相似文献   

3.
Judith E. Skog 《Brittonia》2001,53(2):236-269
The paleobiogeography of the extant leptosporangiate fern families present in the Mesozoic is reviewed based mainly on data from megafossils that possess enough characters to be assigned to a family. Times of first appearances are discussed for each family, followed by their distribution throughout the Mesozoic. Paleolatitudes and climatic conditions indicate that first appearances of many fern families occur about or above 30° and in conditions of higher moisture. Much of fern distribution in the past was likely due to long-distance dispersal.  相似文献   

4.
Southern Nigeria represents one of the richest zones of vegetational wealth of Nigeria. The land surface is dominated by plants under 200 m.a.s 1. Folk utilization of pteridophytes by the southern Nigerians was studied. The results of this survey display an interesting diversity and distribution of ferns and fern-allied plants used as medicines, food, cosmetics, and manure in southern Nigeria. The data were compiled from frequent field trips conducted in 40 local government areas (LGAs). A total of 36 plant species belonging to 22 families were identified. Plant specimens and information were collected directly from the local inhabitants in villages and periurban towns. Our literature survey showed little or no documentation of ethnobotanical studies on pteridophytes of this region. Therefore, the present communication serves to bridge the gap. Thus, these pteridophytes could provide a vital source for healthcare and economic revenue after appropriate pharmacological analysis by patents.  相似文献   

5.
通过比较分布于西双版纳热带雨林林下生境中的附生鸟巢蕨(Neottopteris nidus)和地生网脉铁角蕨(Asplenium finlaysonianum)的光合特征和光合诱导特性,来研究不同生态型蕨类植物的光斑利用策略。研究结果表明,2种蕨类植物的最大净光合速率、暗呼吸速率、表观量子效率、光饱和点和光补偿点没有显著差异,但网脉铁角蕨的最大气孔导度远远高于鸟巢蕨,表明后者具有更强的光合水分利用效率。在暗处理3/J',时接着光照(光强为20I~mol-m-2,s。‘)30分钟后,网脉铁角蕨的初始气孔导度显著高于鸟巢蕨。连续照射饱和强光后,网脉铁角蕨达到最大净光合速率50%(T50%)和90%的时间(T90%)比鸟巢蕨短:网脉铁角蕨和鸟巢蕨的T50%分别为0.57和5.31分钟,T90%分别为5.85和26.33分钟。诱导过程中,气孔导度对强光的响应明显滞后于净光合速率。鸟巢蕨达到最大气孔导度的时间明显比网脉铁角蕨慢,但在光合诱导消失过程中2种蕨类植物的光合诱导维持能力却没有显著差异。上述结果表明,与大多数地生林下植物(如网脉铁角蕨)相比,附生鸟巢蕨的水分保护比碳获得更重要,但却限制了附生蕨对光斑的利用。  相似文献   

6.
SHEFFIELD, E., WOLF, P. G., HAUFLER, C. H., RANKER, T. A. & JERMY, A. C, 1989. Are-evaluation of plants referred to as Pteridiutn herediae (Colmeiro) Love & Kjellqvist. Based on perceived differences in morphology, chromosome number and habitat, specimens of Pteridiutn from southern Spain have been segregated by previous authors as a species distinct from Pteridium aquilinum , and called Pteridium herediae. However, type specimens of this taxon cannot be found. New collections of Pteridium from similar habitats in the area were examined and analysed in the present study and the results compared with those from British plants (P. aquilinum). The Spanish plants were not found to differ significantly from P. aquilinum morphologically, and all yielded chromosome counts (sporophytes, 104; gametophytes, 52) considered typical for the genus. Genotype frequency data obtained from isozyme electrophoresis of Spanish and British Pteridium yielded a genetic identity of 0.86; well within intraspecific distances found in other ferns.
These data indicate that there are currently no grounds for accepting that a form of Pteridium , distinguishable from P. aquilinum on the basis of differences in morphology, chromosome number, habitat or biochemistry, exists on the limestone soils of the Sierra de Cazorla region of southern Spain.  相似文献   

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报道浙江蕨类植物2种新记录,即假耳羽短肠蕨Diplazium okudairai Makino、大盖铁角蕨Asplenium bullatum Wall.ex Mett.。凭证标本存于景宁畲族自治县自然资源和规划局(林业局)标本室。  相似文献   

9.
Using cheilanthoid ferns, we provide an example of how DNA barcoding approaches can be useful to the horticultural community for keeping plants in the trade accurately identified. We use plastid rbcL, atpA, and trnG-R sequence data to demonstrate that a fern marketed as Cheilanthes wrightii (endemic to the southwestern USA and northern Mexico) in the horticultural trade is, in fact, Cheilanthes distans (endemic to Australia and adjacent islands). Public and private (accessible with permission) databases contain a wealth of DNA sequence data that are linked to vouchered plant material. These data have uses beyond those for which they were originally generated, and they provide an important resource for fostering collaborations between the academic and horticultural communities. We strongly advocate the barcoding approach as a valuable new technology available to the horticulture industry to help correct plant identification errors in the international trade.  相似文献   

10.
To elucidate the life cycle time schedule of semi-evergreen ferns at natural sites in Sapporo, the chronological age for sporophyte maturation was estimated from the increase in the number of veins (NV, number of midrib branches) from overwintered to newly expanded leaves. The measurements were conducted on populations ofPolystichum braunii, Polystichum tripteron andDryopteris crassirhizoma at altitudes of 50–650 m on Mt. Teine to compare the interspecific maturation age of sporophytes. The mean age for sporophyte maturation was estimated to be 7.6 yr forP. braunii, 16.5 yr forP. tripteron and 12.6 yr forD. crassirhizoma. The minimum ages (1% fertility rate) for sporophyte maturation ofP. braunii, P. tripteron andD. crassirhizoma were 5.8, 11.0 and 7.9 yr, respectively. The maturation age was shortest forP. braunii and longest forP. tripteron. The maturation age of a species thus seems to differ according to altitude and habitat, and that of the present three species seems to be influenced by the geographical location of the species distribution. Contribution No. 3315 from the Institute of Low Temperature Science, Hokkaido University.  相似文献   

11.
This paper re-examines the species of Triplophyllum in the neotropics. The indument of the laminae (hairs and glands) provides many characteristics for distinguishing the species. Nine species are recognized, including three new ones: T. boliviense, T. chocoense, and T. glabrum. New combinations are made for T. hirsutum and T. perpilosum . A key is provided to distinguish the species, and all species are described and illustrated. The spores of the neotropical species are like those from African and Madagascan species. As such, they offer no evidence to determine whether the neotropical species form a monophyletic clade within the genus.  相似文献   

12.
中国蕨类植物区系的初步研究   总被引:64,自引:8,他引:56  
对中国蕨菜植物区系组成和科属的地理成分进行了统计分析,结果表明:中国蕨类植物区系具有区系成分丰富、起源古老、区系联系广泛、热带性质显著以及特有现象不明显的特点。  相似文献   

13.
该文报道了广西蕨类植物新记录7种,即蕨萁(Botrychium virginianum)、澜沧凤了蕨(Coniogramme serrulata)、筱英凤尾蕨(Pteris xiaoyingae)、卵果双盖蕨(Diplazium ovatum)、厚叶实蕨(Bolbitis hainanensis)、河口实蕨(B.hekouensis)和粗齿鳞毛蕨(Dryopteris juxtaposita),并列出了这些种的标本引证和地理分布。  相似文献   

14.
湖南蕨类植物新记录   总被引:2,自引:0,他引:2  
报道了湖南省蕨类植物新记录14种(含1变种),属于10科11属,它们是皱边石杉(Huperzia crispata),倒叶瘤足蕨(Plagiogyria dunnii),华南鳞盖蕨(Microlepia hancie),三轴凤尾蕨(Pteris longipe),蚀盖金粉蕨(Onychium tenuifrons),长羽凤丫蕨(Coniogramme longissima),圆基凤丫蕨(C. emeiensis var. lancipinna),云贵紫柄蕨(Pseudophegopteris yunkweiensis),齿果铁角蕨(Asplenium cheilosorum),狭翅铁角蕨(A. wrightii),腺齿铁角蕨(A. glanduli-serrulatum),翅轴蹄盖蕨(Athyrium delavayi),骨牌蕨(Lepidogrammitis rostrata),显脉星蕨(Microsorium zippelii)。  相似文献   

15.
There has been an interest in using hyperaccumulating plants for the removal of heavy metals and metalloids. High selenium (Se) concentrations in the environment are detrimental to animals, humans, and sustainable agriculture, yet selenium is also an essential nutrient for humans. This experiment was conducted to screen fern plants for their potential to accumulate selenium. Eleven fern species, Pteris vittata, P. quadriaurita, P. dentata, P. ensiformis, P. cretica, Dryopteris erythrosora, Didymochlaena truncatula, Adiantum hispidulum, Actiniopteris radiata, Davallia griffithiana, and Cyrtomium fulcatum, were grown under hydroponic conditions for one week at 20 mg L(-1) selenate or selenite. Root Se concentrations reached 245-731 and 516-1082 mg kg(-1) when treated with selenate and selenite, respectively. The corresponding numbers in the fronds were 153-745 and 74-1,028 mg kg(-1) with no visible toxicity symptoms. Only three fern species were able to accumulate more Se in the fronds than the roots, which were D. griffithiana when treated with selenate, P. vittata when treated with selenite, and A. radiata regardless of the forms of Se. A. radiata was the best species overall for Se accumulation. More research is needed to further determine the potential of the fern species identified in this study for phytoremediation of the Se contaminated soils and water.  相似文献   

16.
To test our hypothesis of hybrid formation involving the ‘independent gametophyte’ phenomenon in ferns, we identified the genomic formulae and ploidy level of gametophytes of the Vandenboschia radicans complex at the periphery of a sporophyte population. We identified haploid gametophytes of V. kalamocarpa (one of the two putative parents of V.×stenosiphon) in a hybrid sporophyte population in Japan that lacks fertile non‐hybrid individuals. Furthermore, diploid sporophytes of the species were not found within a 50‐km radius. This finding supports a hypothesis of hybridization involving the ‘independent gametophyte’ phenomenon and provides a new perspective on the geographical distribution of fern hybrids.  相似文献   

17.
武陵山区是中国植物多样性研究的热点地区之一。1988年,中国科学院植物研究所等单位完成了对该地区的第一次生物多样性普查[1],由于行政区域重新划定和交通条件限制等原因,诸多区域未涉及。近期,中南民族大学在国家科学技术部科技基础性工作专项的支持下,再次对该区域(湖北部分)进行了野外调查并采集了大量标本,以相关书籍[2-6]和近期发表的相关调查结果[7-13]为依据,鉴定出一批在湖北省区域内未曾记录的蕨类植物并将陆续予以报道。本文报道了其中的11种1变种,分别隶属于5科10属,凭证标本均存于中南民族大学植物标本馆( HSN),各种类形态特征见图1。  相似文献   

18.
The epiphytic fern genus Serpocaulon (Polypodiaceae) comprises 42 species nested within the neotropical clade of the family together with genera such as Campyloneurum, Grammitis, Microgramma, Niphidium, Pleopeltis, Pecluma, Polypodium and Terpsichore. Although Serpocaulon is a well-supported genus, its intra-specific relationships are still not completely resolved. The morphological dataset for Serpocaulon and related genera is therefore expanded here with information on spore morphology to provide additional information for phylogenetic consideration. Spores have been collected from herbarium vouchers and acetolysed for light and scanning electron microscopy. All members of the neotropical clade have monolete spores, except for Grammitis and Terpsichore, which have trilete spores. Both verrucate and papillate ornamentation types are recognised. The palynological analysis shows close similarity between spores of Serpocaulon, Campyloneurum, Pleopeltis and Polypodium and supports close phylogenetic relationships between these taxa. Species of the grammitid clade, although nested within the Polypodiaceae, have spore morphology that supports a separate position.  相似文献   

19.
通过对九连山的蕨类植物多样性调查,报道江西省蕨类植物新记录两种,即百越凤尾蕨(Pteris fauriei Hieron.var.chinensis Ching et S.H.Wu)和百山祖双盖蕨[Diplazium baishanzuense(Ching&P.S.Chiu)Z.R.He]。凭证标本保存于江西省九连山国家级自然保护区管理局植物标本室(JNR)。  相似文献   

20.
Peter Raven, in 1963, included two fern taxa of the genus Botrychium in his list of plant species exhibiting American amphitropical bipolar disjunctions. He attributed the southern hemisphere occurrences to post‐Pleistocene long‐distance dispersal from counterparts in the northern hemisphere, probably assisted by annual bird migrations between the disjunct areas. Using genetic evidence gathered through worldwide analyses of phylogenetic relationship in Botrychium, we now review and reconsider Raven's conclusions. Genetic similarities indicate that South American Botrychium dusenii is an allotetraploid taxon closely related to B. spathulatum, a North American endemic, and that B. lunaria in New Zealand possesses a genotype identical to that of a taxon in North America derived through introgressive hybridization between B. lunaria and an endemic North American species, B. neolunaria. Both North American counterparts exhibit Raven's characteristics of bipolar disjuncts in their occurrence in mountain and coastal meadows, copious production of small propagules (spores in Botrychium), occurrence in habitats frequented by transpolar bird migrants, and ability to found new colonies through inbreeding. We discuss these characteristics in Botrychium and relative to other ferns and suggest further studies on Botrychium and related taxa to address questions of time, number, and mode of bipolar dispersals.  相似文献   

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