首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
A new species, Jurinea tortumensis A. Duran & B. Dogan (Asteraceae), is described and illustrated from Anatolia, Turkey. The species grows on serpentine stony places in the Tortum district (Erzurum Province) in northeast Anatolia. It is morphologically similar to J. consanguinea DC. The pollen characteristics and achene surface morphology of J. tortumensis and J. consanguinea are examined by SEM. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology, conservation status and biogeography of the species are also presented. In addition, the geographical distributions of the new species and other related species are mapped.  相似文献   

4.
《Journal of bryology》2013,35(1):56-68
Abstract

A new species of Pseudocrossidium R.S.Williams, P. exiguum M.J.Cano &; J.A.Jiménez, is described from South America (Argentina, Brazil and Peru). The species is distinguished morphologically by its lingulate to oblong-ovate leaves, leaf marginal cells not or scarcely differentiated from inner, costa ending below apex or percurrent, and semicircular to elliptical in cross-section with two guide cells, scarcely differentiated perichaetial leaves and peristome of short and straight teeth. Drawings and light microscope photographs of the new species are provided. The principal distinctive characters that separate it from the nearest species of Pseudocrossidium and related genera are discussed.  相似文献   

5.
Juncus articulatus, a species introduced to Australia, is codominant over large areas of Mother of Ducks Lagoon but is rare in other lagoons. It occurs widely within the lagoon but is concentrated in lower, wetter areas that are more disturbed by birds and cattle. This suggests that J. articulatus may be separated over elevation (and therefore water regime) and disturbance gradients from the native grass Glyceria australis, the dominant species in the lagoon. This paper compares the growth and interaction of G. australis and J. articulatus under different water regimes. The species responded differently to water regime both in monoculture and in mixture. Above ground production of J. articulatus was greatest under fluctuating water levels, least under a damp water regime and intermediate under flooded conditions. G. australis production was greatest under the damp, least under the flooded and intermediate under the fluctuating water regime. The outcome of interaction is dependent on water regime and time. After one year J. articulatus was the superior competitor under all water regimes. At the end of two years J. articulatus was still the superior competitor under fluctuating and flooded water regimes but not under the damp regime. The change in outcome after two years was due to the competitive superiority of G. australis during the second year under all water regimes. The relative importance and the management implications for the invasive potential of J. articulatus are assessed in shallow Australian wetlands with fluctuating water regimes.  相似文献   

6.
Haplodontium zangii X.R.Wang &; J.C.Zhao, a new moss species from Xizang, China, is described and illustrated. Previously, specimens of H. zangii have been identified as Mielichhoferia himalayana Mitt. However, H. zangii is distinctly different from M. himalayana in having excurrent costae with short awns (vs long denticulate awns), short-pyriform capsules, 0.8–1?mm (vs long-pyriform capsules, 2.5–3?mm), and densely papillose exostome teeth (vs smooth or vertically striped exostome teeth). Haplodontium zangii is similar to H. macrocarpum (Hook.) J.R.Spence, which was traditionally placed in Mielichhoferia Nees &; Hornsch. as M. macrocarpa (Hook.) Bruch &; Schimp. The main differences between H. zangii and H. macrocarpum are in the morphology of the leaves, capsules, guide cells, and stomata. Mielichhoferia himalayana and another Chinese species of Mielichhoferia, M. sinensis Dix., are also transferred to Haplodontium Hampe, a new genus in the bryoflora of China, as H. himalayanum (Mitt.) X.R.Wang &; J.C.Zhao and H. sinensis (Dix.) X.R.Wang &; J.C.Zhao. A morphological comparison and a key to the three species of Haplodontium in China as well as to H. macrocarpum, a species that is likely to be found in China, are provided.  相似文献   

7.
The genus Jacaranda shows notable karyotype stability and a prevailing self‐sterile breeding system with evidence of late‐acting self‐incompatibility in several species. However, some studies have indicated self‐compatibility in J. mimosifolia, a species cultivated worldwide in tropical and subtropical areas. Jacaranda cuspidifolia is a closely related species with natural distribution broadly overlapping with that of J. mimosifolia, and manual heterospecific pollination studies have indicated that these species are interfertile, but there is no report on the breeding system of the former. In this study, we used hand‐pollination experiments, pistil longevity, epi‐fluorescence and histological analysis of post‐pollination events to determine the breeding system of J. cuspidifolia. We also employed intra and interspecific crosses and seed germination tests to reevaluate the breeding system of J. mimosifolia and the inter‐fertility between the two species. Some fruits were initiated from self‐pollinated pistils in J. mimosifolia, but none of them reached maturity. On the other hand, complete absence of fruit development by self‐pollination was verified in J. cuspidifolia, while in situ pollen tube growth and histological analysis of post‐pollination events in selfed pistils revealed the characteristic ovule penetration, fertilization and endosperm initiation also observed in other bignoniaceous species with late‐acting self‐incompatibility. Low outbreeding barriers seem to operate between these species because reciprocal interspecific crosses and hybrid seed germination tests indicated they are bilaterally interfertile. However, fruit/seed production and seed germinability were significantly lower when pistils of J. cuspidifolia were pollinated with pollen of J. mimosifolia, compared with crosses in the opposite direction, which indicates a partial unilateral incompatibility. This result is discussed in the context of the possible occurrence of self‐compatibility in J. mimosifolia. The low level of incongruity operating between the two species also points to their recent evolutionary divergence.  相似文献   

8.
《Journal of bryology》2013,35(4):589-593
Abstract

Calymperes schmidtii Broth. in J. Schmidt and C. subintegrum Broth. in J. Schmidt, hitherto regarded as conspecific, are shown to represent distinct species.  相似文献   

9.
In this paper, we propose that Rhododendron clementinae Forrest ex W. W. Sm. subsp. aureodorsale W. P. Fang ex J. Q. Fu should be recognized at species rank as Rhododendron aureodorsale (W. P. Fang ex J. Q. Fu) Y. P. Ma & J. Nielsen. This species is similar to R. clementinae, but has an isolated distribution range, and differs by having tawny indumentum without pellicle on the abaxial leaf surface, sparse hairs on both pedicel and sepals, and always 7 corolla lobes.  相似文献   

10.
Justicia brevipedunculata, a new species ofJ. sect.Ansellia endemic to Tanzania, is described and illustrated. Detailed palynological information is given, and relationships to other species of the section are discussed.  相似文献   

11.
Artabotrys manoranjanii M. V. Ramana, J. Swamy & K. C. Mohan (Annonaceae), a new species from the foot hills of Saddle Peak National Park, north Andaman Islands, is described and illustrated. Its fleshy petals and prominent stigmas, distinguish it from all previously known species. Its affinity with A. parkinsonii Chatterjee, a Myanmar species, and A. grandiflorus King, a species from Malayan peninsula, is deliberated.  相似文献   

12.
Primulina suichuanensis X. L. Yu & J. J. Zhou, a new species of Gesneriaceae from Jiangxi, China, is described and illustrated. Morphologically, the new species is most similar to P. roseoalba, but differs by entire leaf blade margin, narrowly ovate bracts, reddish–purple or bluish–purple corolla, 3.0–3.4 cm long corolla tube, white filaments, and 3.6 cm long pistil. It flowers from September to November.  相似文献   

13.
In the context of an ongoing revision of the orchid genus Oberonia in Thailand, we describe and illustrate a new species under the name O. pygmaea Bunpha, H. A. Pedersen & Sridith. Vegetatively, the tiny new species is particularly similar to O. rufilabris Lindl. (widespread in mainland southeast Asia, including Thailand), whereas its floral morphology comes closest to the much larger O. costeriana J. J. Sm. from Sumatra, Java and Sulawesi. So far, O. pygmaea is only known from Pang Ung in the northern Thai province of Mae Hong Son, but we suggest that it should also be searched for in hill evergreen forest in adjoining parts of the Dawna Range, both in Thailand and Myanmar.  相似文献   

14.
Jurinea pinnata (Lag.) DC. is one of the three species of the genus that grows in the Iberian Peninsula. This species grows on gypsum and dolomite, substrates rich in endemic taxa. Actually, the genus Jurinea Cass. is particularly rich in endemic taxa associated with special substrates. The island-like distribution of J. pinnata makes it an interesting case for the study of genetic differentiation processes. The geographical proximity of J. pinnata and J. humilis makes this evolutionary puzzle even more difficult to solve. These facts could affect the genetic attributes of the species as far as diversity and differentiation are concerned. Our field research involved the sampling of individuals from eight populations of J. pinnata. Of them, six were located in the Guadix-Baza Basin. We used sequences of ribosomal and plastid DNA to perform the genetic analyses. Results revealed no differences between individuals occurring on the two kinds of substrates and evidences of hybridization between J. pinnata and J. humilis. Furthermore, the phylogenetic analysis revealed a possible polyphyletic origin for the adaptation to special substrates within the Jurinea genus, while monophyly was observed in species from the Iberian Peninsula. This could indicate a more general adaptation to arid or saline environments.  相似文献   

15.
A new orchid species, Gastrodia sui C. S. Leou, T. C. Hsu & C. L. Yeh is described and illustrated from Taiwan. The new species is closely related to G. callosa J. J. Sm. but distinguishable by the number and position of calli inside the perianth tube, the fused ratio of perianth lobes, and the structure of the lip and column. It is so far only found in the area of Mt Lilung in southern Taiwan.  相似文献   

16.
 The mode of reproduction, pollen production, chromosome numbers, genetic variation (RAPD, allozymes) and overall similarity were studied in 6 species of Hieracium sect. Alpina in the Tatry Mts. (the Western Carpathians, Slovakia). All species were confirmed to be agamospermous and, except of H. krivanense and H. slovacum, lacking pollen grains. For the first time, a chromosome number is reported for H. krivanense (2n=4x=36). Considerable genetic variation was revealed in H. alpinum and a correlation between geographic and genetic distances was found in this species. Between-population variation in RAPD and allozyme phenotypes was found in H. pinetophilum and H. crassipedipilum. In all other species, allozyme and RAPD variation was low or absent. With few exceptions, the species differ in their allozyme as well as RAPD patterns. The relatedness of one population of endemic H. slovacum and H. halleri was confirmed. It is shown, that Carpathian species of the H. fritzei group are derived from at least two ancestors. Received July 3, 2000; accepted June 24, 2002 Published online: November 20, 2002 Addresses of the authors: H. Štorchová, (e-mail: storchova@ueb.cas.cz) Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 135, CZ-165 00 Praha 6, Czech Republic. I. V. Bartish, J. Chrtek Jr., J. Kirschner, M. Tetera, J. Štěpánek, Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 Pruhonice, Czech Republic.  相似文献   

17.
Tropaeolum austropurpureum (J.M. Watson & A.R. Flores) J.M. Watson & A.R. Flores, stat. nov., based on Tropaeolum hookerianum Barnéoud subsp. austropurpureum J.M. Watson & A.R. Flores, is described, and the new rank is published. Details of the discovery, ecology, and possible evolution of this species are discussed. Instructions for its cultivation are given.  相似文献   

18.
Based on personal collections ofGlobba unifolia Ridl. andG. unifolia var.sessiliflora Holtt., the latter is recognized as a distinct species. As the nameG. sessiliflora is already occupied, the nomen novumG. corneri is proposed in honour of Prof. DrE. J. H. Corner, who was the first collector of the plant.Dedicated to Prof. DrE. J. H. Corner (Cambridge) on the occasion of his 85th birthday on January 12th, 1991.  相似文献   

19.
The taxonomic position of an actinomycete isolated from soil was evaluated using a polyphasic approach. The organism, strain J72, was found to have chemical and morphological properties consistent with its assignment to the genus Gordonia. A nearly complete 16S rDNA sequence of the strain was determined by direct sequencing of the amplified gene. The tested strain formed a distinct phylogenetic line within the evolutionary radiation occupied by the genus Gordonia and was most closely related to G. polyisoprenivorans DSM 44302T. The phenotypic profile of strain 372 readily distinguishes it from representatives of the validly described species of Gordonia. The combined genotypic and phenotypic data show that strain J72 merits recognition as a new species of Gordonia. The name proposed for the new species is Gordonia sinesedis; the type strain is J72T (= DSM 44455T = NCIMB 13802T). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.
7. GENERAL NOTES     
Hockey, P. A. R., Brooke, R. K., Cooper, J., Sinclair, J. C. &; Tree, A. J. 1986. Rare and vagrant scolopacid waders in southern Africa. Ostrich 57: 37–55.

Records of rare scolopacid waders in southern Africa are reviewed. 374 records of 15 species are accepted: seven of four Nearctic species. 51 of four Holarctic species and 316 of seven Palaearctic species. Their spatial and temporal (year and season) occurrence is analysed and their habitat requirements in southern Africa are described.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号