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1.
《Journal of bryology》2013,35(2):122-132
Abstract

Taxonomy of some European species of Ephemerum is reviewed. As in several other recent studies, E. minutissimum Lindb. is regarded as a distinct species from E. serratum (Hedw.) Hampe; it is recorded from N. America (by the newly designated lectotype and other specimens) and Turkey, in addition to Europe. E. serratum var. angustifolium Bruch & Schimp. may be a synonym of E. minutissimum; the costate forms E. serratum var. praecox A.W.H.Walther & Molendo and E. intermedium Mitt. in Braithw. are treated as synonyms of E. serratum s.str. Type specimens of E. stellatum H.Philib. are described, a lectotype is designated and it is placed as a synonym of E. serratum s.str. E. hibernicum Holyoak & V.S.Bryan is regarded as a synonym of E. rutheanum Schimp. in Ruthe. The latter is shown to be a rare, European endemic taxon with modern records from Ireland, S. Wales, Germany and The Netherlands, and old records from France and W. Poland; a lectotype is designated. Forms intermediate between E. sessile (Bruch.) Müll.Hal. and the N. American E. crassinervium (Schwägr.) Hampe occur in several countries in W. Europe, some of them indistinguishable from some of the American plants; forms intermediate between E. sessile and E. rutheanum are recorded from S. Portugal and (rarely) Ireland. Differences between E. crassinervium, E. sessile and E. rutheanum in characters of leaves, tubers and capsules are shown to be slight, with considerable overlap. Hence all three taxa are treated as subspecies of E. crassinervium. A revised key to European Ephemerum and Micromitrium is presented.  相似文献   

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The spores of Syntrichia ruralis (Hedw.) F. Weber and D. Mohr., S. princeps (De Not.) Mitt., S. subulata (Hedw.) F.Weber and D.Mohr var. subulata, S. subulata (Hedw.) F.Weber and D.Mohr var. angustata (Schimp.) J.J. Amann and S. subulata (Hedw.) F.Weber and D.Mohr var. graeffii Warnst. were studied by light and scanning electron microscopy for the first time. The apertural region consists of a leptoma in all spores. All taxa of the family are uniform in their spore morphology. The spores of the five taxa are of granuloid type. The spore wall of the Pottiaceae family includes sclerine (the distinction between exine and perine may be difficult to define) and intine. The taxonomy of the genus Syntrichia is discussed on the basis of its spore morphology.  相似文献   

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《Journal of bryology》2013,35(3):216-219
Abstract

Indopottia zanderi, a new genus and species of the Pottiaceae, is described from the Silent Valley National Park in the Western Ghats in Peninsular India. The distinctive features of Indopottia are the leaf cells being weakly convex on both surfaces, costal stereid-band semicircular in cross-section, guide cells rounded-ovate or semicircular, seta short and operculum very long. The affinities of the allied genera, Ganguleea, Tortula and Weisiopsis, are discussed. The new genus Indopottia may be placed in the tribe Hyophileae.  相似文献   

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国产赖草属(禾本科)两个类群的修订   总被引:1,自引:0,他引:1  
根据标本研究、野外考察和实验观察,对国产赖草属Leymus两个类群进行了分类修订,将阿尔金山赖草Leymus arjinshanicus D.F.Cui和L.aerginshanicus D.F.Cui ssp.ruoqiangensis(S.L.Lu&Y.H.Wu)D.F.Cui处理为若羌赖草L.ruoqiangensis S.L.Lu&YH.Wu的新异名,将纤细赖草L.secalinus(Georgi)Tzvel.var.tenuis L.B.Cai提升为一个独立的种L.tenuis(L.B.Cai)L.B.Cai.  相似文献   

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《Journal of bryology》2013,35(2):89-95
Abstract

Ephemerum hibernicum sp. nov. is described from inundation zones of two lakes and a river in north-central Ireland and a river in western Ireland. It is most similar to E. crassinervium and E. sessile, but differs from both of these in several characters of the leaves. In particular, papillae on the upper lamina are much lower than in most E. crassinervium, while the leaves are longer and wider than in E. sessile, with a wider lamina towards the leaf apex, less well-defined costa and sometimes with large spinose marginal teeth. Ephemerum hibernicum is a rare species and its specialized habitat merits conservation.  相似文献   

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James L. Reveal 《Brittonia》1981,33(3):441-448
Three unnamed buckwheats listed by the United States Fish and Wildlife Service in December 1980 as potentially endangered or threatened plants are formally proposed:E. crosbyae from Lake Co., Oregon;E. grande var.dunklei from San Miguel Island, Santa Barbara Co., California; andE. ovalifolium var.williamsiae from Washoe Co., Nevada. Several other species proposed by the Fish and Wildlife Service as potentially endangered or threatened (E. allenii, E. correllii, E. eremicum, E. floridanum, E. lemmonii, E. sp./sp. nov. ined. [=E.libertini], E. tumulosum, E. umbellatum var./var. nov. ined.,E. umbellatum var.minus, E. vestitum, andE. zionis var.coccineum) are discussed and evidence is given why they cannot be considered endangered or threatened under the present Endangered Species Act of 1973, as amended.  相似文献   

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Melanism is a common phenomenon in the animal kingdom. While the occurrence of melanism in lagomorphs has been less studied, this phenomenon has led to systematic confusion among different forms of pikas (Ochotona) and hares (Lepus). Within Ochotona, the Pianma black pika (O. nigritia) was established primarily based on its pelage phenotype variation compared with the sympatric Forrest's pika (O. forresti). The Gaoligong pika (O. gaoligongensis) was also described based on pelage color differences with O. forresti. However, the specific status of these two taxa has been questioned for several years. We conducted a detailed examination of the cranial characters used for the initial diagnosis of each of these forms (O. forresti, O. gaoligongensis and O. nigritia). Insignificant differences were displayed among these species, thus contradicting the classification of O. gaoligongensis and O. nigritia as separate species. Within Lepus, the Manchurian black hare (Lepus melainus) was also initially described based on the melanistic pelage possessed by this form. We conducted a detailed examination of the cranial characteristics of L. melainus and the sympatric Manchurian hare (L. mandshuricus) and confirmed the synonomy of these forms; L. melainus represents melanistic individuals of L. mandshuricus. These taxonomic mistakes probably resulted from underestimating the prevalence of melanism and the potential for adaptative variation of pelage coloration in nature. A more detailed study on the genetic background leading to the occurrence of melanistic lagomorphs is needed.  相似文献   

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Enrique Forero 《Brittonia》1972,24(2):143-147
Stryphnodendron campestre Forero andS. guianense (Aubl.) Benth. ssp.glandulosum Forero are described and illustrated, and notes on the nomenclature ofS. adstringens and on the exclusion ofS. colombianum from the genus are included.  相似文献   

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The spores of Bruchia uleana, B. uruguensis, Eobruchia bruchioides, Trematodon ambiguus, T. aureus, T. brevifolius, T. longlcollis, T. reflexus and T. vaginatus were studied by light and scanning electron microscopy. The spore wall of the family Bruchiaceae includes sclerine (the distinction between exine and perine may be difficult to define) and intine. The aperture may be surrounded or not by one or more rings of ornamentation elements. Two basic types of spore were recognized: one characterized by a gemmoid surface and the other with elongated processes and two types of ornamentation in the apertural region. The spores of the taxa studied support the separation of the Bruchiaceae from the Dicranaceae.  相似文献   

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The genus Reynoutria is represented by four taxa in the Czech Republic – R. japonica var. japonica and compacta, R. sachalinensis and R. × bohemica. Using isoenzyme analysis, we determined the degree of genotype variability in all taxa and compared clones of R. japonica var. japonica from the Czech Republic with those from Great Britain. While the rarely occurring tetraploid variety R. japonica var. compacta possesses low variability, the octoploid female clone of R. japonica var. japonica is genetically uniform in the 93 clones sampled and belongs to the same genotype that is present in the whole Europe. R. japonica var. japonica can be fertilized by the pollen of tetraploid R. sachalinensis and a hexaploid hybrid R. × bohemica is produced. In R. sachalinensis, 16 genotypes were found in the 50 clones sampled. R. × bohemica is genetically the most diverse taxon in the study area, with 33 genotypes recorded among 88 clones sampled.  相似文献   

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A new genus and speciesMonogereion carajensis and a new species ofAgeratum, A. glomemtum, are described from Para, Brazil. The relationships of the new genus and species are discussed.  相似文献   

20.
发酵甜高粱汁耐高浓度酒精酵母菌的选育   总被引:3,自引:0,他引:3  
采用负染色计数法从非自然诱变菌株中成功地选育了一株以C4植物甜高粱汁做基质发酵生产液体生物燃料(酒精)的酵母菌株,产酒率最高达12.80%(V/V).  相似文献   

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