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1.
Eleven native Taraxacum species from Norden are described as new: T. acutilimbatum, T. frondatum, T. latulum, T. thorvaldii, T. wendtii and T. wessbergii (all in T. sect. Erythrosperma), T. danicum (sect. Palustria), T. conspersum and T. lentiginosum (sect. Naevosa), T. pietii‐oosterveldii (sect. Celtica) and T. ovillum (sect. Spectabilia). They are compared with morphologically similar species, and their ecological preferences are outlined. Known distribution areas and lists of paratypes are given. Taraxacum polyschistum Dahlst. forma oelandicum G. E. Haglund (sect. Erythrosperma) is given status of species.  相似文献   

2.
Among Swedish Hieracium sect. Oreadea (Fr.) Arv.‐Touv., more than 100 taxa have been recognized by various experts but, except for a regional monograph from 1894 there are no thorough published revisions of the group and many of the names have never been validly published. At the same time, some of the oldest names have been variously applied to morphologically clearly different species. In the present study, 5000 specimens in Swedish herbaria have been revised using both traditional and statistical morphometric methods and the complicated nomenclature has been disentangled. Twenty‐eight species are recognized and described with diagnostic keys and illustrations aiding identification and their known distributions are mapped. Six species are described as new to science (viz. H. marinum T. Tyler, H. eulasium Dahlst. ex T. Tyler, H. victoriae T. Tyler, H. falcifolium Johanss. ex T. Tyler, H. guldbergense Folin ex T. Tyler and H. hispidosum Dahlst. ex T. Tyler) and 3 additional names are raised to the specific rank (viz. H. gigantocybe (Dahlst.) T. Tyler, H. hilare (Dahlst. ex Omang) T. Tyler and H. tanyphyllum (Dahlst. ex Zahn) T. Tyler). Lectotypes are designated for 50 names based on material from Sweden, Norway or Finland and one name is neotypified. Except for a few infraspecific names for which all original material appears to be lost, all names based on material from Sweden are typified. However, it is concluded that albeit the number of taxa is relatively low, the species of H. sect. Oreadea are morphologically less distinct and clear‐cut than those of other widespread Scandinavian sections of the genus. Many of the characters that are most important in other sections of the genus are either invariable or unreliable in H. sect. Oreadea. Thus, the taxonomy has to rely on characters more subjected to environmentally‐induced modification. Furthermore, members of this section exhibit great morphological plasticity, possibly connected to their preference for exposed rocky habitats where the environmental conditions may be both severe and unpredictable.In addition, due to their ecological demands, they are confined to habitats that have always been both strongly fragmented and restricted in size giving rise to multiple small and locally adapted local populations. The section is here circumscribed in agreement with previous Scandinavian authors, i.e. including both the H. schmidtii‐group sometimes referred to H. sect. Stelligera and the H. norvegicum group approaching H. sect. Tridentata, but it is concluded that the section is relatively heterogeneous and that further studies aiming at the identification of more natural supraspecific taxa are much needed.  相似文献   

3.
Six taxa of the genus Taraxacum sect. Erythrosperma were analyzed morphometrically using multivariate methods. A total of 391 specimens from Slovakia, Hungary, Czech Republic and Austria were studied. This study aimed to explore if leaf shape can be used to differentiate diploids and triploids, to verify if triploid microspecies deserve separate taxonomic status, and if the diploid plants can be divided into phenotype groups. The analysis of leaf-shape variability revealed no notable difference between diploid and triploid plants. The analysis of the triploid microspecies T. cristatum, T. danubium, T. parnassicum, T. princeps and T. proximum s.l. resulted in their differentiation into separate groups. For differentiation, the characters with a higher determination value were employed, especially the shape of a terminal leaf lobe, the position of outer bracts, the number of lateral lobes and their termination. Analyzing a very variable diploid species T. erythrospermum enabled the definition of four basic phenotypes based on leaf shape. The phenotypes differed in leaf size and shape in relation to environmental factors such as intensity of light, nutrients, moisture, or disturbance. In conclusion, to evaluate the taxonomic status of particular taxa within Taraxacum sect. Erythrosperma it is inevitable to understand the complex leaf-shape variability, being a result of both genetic variability and phenotypic plasticity.  相似文献   

4.
Sargassum C. Agardh (1820) is a taxonomically difficult genus distributed worldwide and reported as the most species‐rich genus of the Fucales. It is especially abundant in the Pacific where decreasing species richness is reported to occur from west to east. New Caledonia has been recognized as one of the hotspots of Sargassum diversity; however, species lists available for this region are old and incomplete and have not yet been updated with regard to the latest taxonomic revisions published. This study aimed at revising Sargassum diversity in New Caledonia and to assess its geographic affinities with neighboring Pacific regions. We used combined morphological and DNA analyses on new collections and examined numerous type specimens. Although 45 taxa have been listed in the literature, most of them have been either transferred to synonymy since or misidentified, and in this study, only 12 taxa were recognized as occurring in New Caledonia. They belong to the subgenus Sargassum sect. Binderianae (Grunow) Mattio et Payri (2), sect. Ilicifoliae (J. Agardh) Mattio et Payri (2), sect. Polycystae Mattio et Payri. (1), sect. Sargassum (4), sect. Zygocarpicae (J. Agardh) Setch. (2), and subgenus Phyllotrichia (Aresh.) J. Agardh (1). New Caledonian Sargassum flora appeared as the second richest in the region after the Pacific coast of Australia, with which it has shown high similarity, and shared species with all neighboring regions. One species, S. turbinarioides Grunow, is considered as endemic to New Caledonia. The low genetic diversity detected among several polymorphic species belonging to sect. Sargassum is also discussed.  相似文献   

5.
Lathyrus sect. Lathyrostylis includes 20 Eurasian species that are more or less xerophytic. They are mainly distributed in South Europe and Southwest Asia, especially in Turkey. The majority of the species inhabits dry meadows, scrubs, Pinus forests, macchies, rocky slopes and screes. The following diagnostic characters are valuable: All species are perennial. The pinnate leaves consist of (1–)2–3(–8) pairs of parallelveined, amphistomatic leaflets and the rachis ending in a simple tip. The style is linear to broadly spathulate but not twisted. Within the section neither subsections nor series can be distinguished. The study is mainly based on herbarium specimens. Only few species had been cultivated. A key to species and subspecies and new maps, mainly based on revised herbarium specimens, are given. Species and infraspecific taxa are described, and their variability, relationships, phytogeography and ecology are discussed. At last some supplements and corrections to the revision of Lathyrus sect. Orobus (Bässler 1973) are added.  相似文献   

6.
The sixty new taxa described in Musci Indici are reviewed. As a result of validation of 54 of these by plates alone, authorities, original specimens and provenance of many have been widely misinterpreted. Evidence from published material, unpublished correspondence and herbarium material demonstrates that W. H. Harvey (1836) is the sole validating author of most of the names; three were validated by J. D. Hooker in 1837, and two names jointly by J. D. Hooker and Harvey in 1840. None was validated by W. J. Hooker, in the past often considered to be the author of some of the names. It is shown that Musci Indici names should be typified by lectotypes; recent typifications of four of the names by ‘holotypes’ and six out of eight published ‘lectotypes’ are untenable as the specimens selected were not original material studied by Harvey, and should be superseded by new lectotypes. Five specimens are selected as new lectotypes. Original material, mostly in Harvey's herbarium in TCD, is identified as most suitable for future lectotypification of the other names. Types for the three names based solely on Royle material are located in LIV and BM. Original Harvey material is also preserved in GL, but most of the Wallich collections in BM, E and elsewhere are not part of the original material. For Neckera blanda no suitable type specimen was located; the original published plate is selected as lectotype with a specimen in BM as a supporting ‘epitype’. Many of the original localities published in 1840 as ‘Nepal’ are shown to be erroneous. As far as possible these are corrected but for some taxa provenance remains doubtful. Twenty-two of the new names are shown not to have been based on material from Nepal; as a result ten species (Acanthorrhynchium papillatum, Brachythecium kamounense, Chaetomitriopsis glaucocarpa, Meiothecium microcarpum, Mitthyridium repens, Rozea fulva, Splachnobryum flaccidum, Sterophyllum radiculosum, Trichosteleum boschii and Trismegistia lancifolia) and Trismegistia lancifolia) are deleted from the Nepal checklist. Twenty-eight of the new species are considered to be reliably based on material from Nepal, and a further five doubtfully so. Rozea microcarpa Broth. is shown to be an synonym of R. fulva (Harv.) M. Fleisch. Past taxonomic confusion between Hypnum cordatum Harv. and Neckera cordata [Hook. ex] Harv. is untangled; the first is shown to be a synonym of Eurhynchium hians (Hedw.) Sande Lac. and the second is the basionym of Penzigiella cordata (Harv.) M. Fleisch.  相似文献   

7.
Phylogenies based on ITS and LSU sequences show that the Sparassis crispa complex comprises several monophyletic clades, in some cases co\rresponding to named taxa (i.e. S. crispa, S. radicata), but others lacking names (i.e. eastern and southwestern North American S. “crispa”). In our study, morphological examination of numerous collections also distinguished subtle differences correlated with geographic distribution. Underlying these problems, several taxa lacked type specimens for taxonomic analysis. In this paper, appropriate epitypes are designated and names assigned. Extensive sexual compatibility experiments, described within, indicate that monokaryon, haploid isolates of collections from North America and Europe are consistently sexually compatible to some degree. Inherent in the study, different “species concepts” were tested, with the “biological species concept,” based on sexual compatibility, being the least restrictive. We propose two new taxa, S. americana and S. americana f. arizonica.  相似文献   

8.
9.
A morphological study of specimens collected by the author and a critical revision of the key herbarium collections revealed a new rather peculiar taxon of Alchemilla occurring in almost every region of the Middle Volga basin, Russia. This novelity is here described as A. schmakovii and images of the principal morphological features of this species are provided. The new species is compared with related species in A. sect. Alchemilla (e.g. A. micans) and sect. Plicatae (e.g. A. breviloba) based on morphological characteristics.  相似文献   

10.
This note is to call attention to a number of marine algal taxa from the Antilles that were described by Placide Duchassaing in his 1850 work Animaux radiaires des Antilles. The mid‐19th century was a period when the distinction between marine invertebrates and some calcified benthic marine algae was still not always clear. The names of these algal taxa were validated, although no figures or details on their specific provenance were provided, other than they were from Duchassaing's collections from the Antilles. Duchassaing assigned his new algal species to the following genera: Galaxaura, Amphiroa, Jania, Melobesia and Nullipora. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

11.
Cross‐sections of roots, stems, petioles and peduncles were investigated in 12 species of Viola distributed mainly in northern Iran: V. kitaibeliana, V. arvensis, V. occulta, V. tricolor (sect. Melanium), V. somchetica (sect. Plagiostigma), V. spathulata (sect. Spathulidium ined.), V. alba, V. odorata, V. sintenisii (sect. Viola subsect. Viola), V. caspia, V. reichenbachiana and V. rupestris (sect. Viola subsect. Rostratae). General anatomical features of Viola species are discussed. The following characters were found to be taxonomically informative: cross‐section shapes of the aerial stem, petiole and peduncle as well as the number of vascular bundles in the aerial stem. In taxa of sect. Melanium, stem cross‐sections are elliptic with two wings, but they are semi‐circular with two wings in taxa of sect. Viola subsect. Rostratae. Within the latter subsection, the number of vascular bundles in the stem can be used to delimit the species V. caspia, V. reichenbachiana and V. rupestris. Calcium oxalate crystals were observed in all vegetative organs of taxa belonging to sect. Viola. All examined taxa had a secondary structure with the exception of V. somchetica. Our results show that anatomical characters are useful for delimiting species, subsections, and sections within Viola.  相似文献   

12.
Five new Conocybe species are described from Russia based on collections made in different parts of the country. One species (C. olivaceopileata) belongs to sect. Conocybe, two species (C. praticola and C. coniferarum) to sect. Mixtae. The ornamented basidiospores of C. confundens and C. incerta is characteristic for sect. Ochromarasmius. All new species are described based on morphology and, in some cases, on DNA sequencing (ITS rDNA). Photos of basidiocarps, illustrations of microstructures and a comparison with similar taxa are given.  相似文献   

13.
A new species, namely Pyrus cordifolia (P. sect. Pashia) is described as new to science, and two new records including P. tamamschianiae (P. sect. Pyrus) and P. theodorovii var. latifolia (P. sect. Argyromalon) are reported for the flora of Iran. These taxa are compared with their closest relatives. Photographs and a distribution map of these taxa as well as an illustration of the new species are presented. An identification key to members of P. sect. Pashia in Iran is provided.  相似文献   

14.
Summary  Seven new names at species rank are proposed in Memecylon sect. Afzeliana Jacq.-Fél., a group of forest shrubs and small trees confined to Guineo-Congolian Africa. The group is centred in Cameroon, where 17 of the 20 species occur. A new flower type, the “star-flower” in Memecylon is revealed, and its taxonomic and ecological importance discussed. Three new, locally endemic species from the South West Province of Cameroon are described, mapped and illustrated: M. kupeanum R. D. Stone, Ghogue & Cheek, M. bakossiense R. D. Stone, Ghogue & Cheek, and M. rheophyticum R. D. Stone, Ghogue & Cheek. Two new names, M. accedens R. D. Stone, Ghogue & Cheek and M. hyleastrum R. D. Stone & Ghogue and one new combination, M. mamfeanum (Jacq.-Fél.) R. D. Stone, Ghogue & Cheek are provided at species level for three taxa originally proposed as varieties of M. afzelii G. Don. The taxon M. arcuatomarginatum var. simulans Jacq.-Fél. is also elevated to species status, as M. simulans (Jacq.-Fél.) R. D. Stone & Ghogue. Conservation assessments are provided for all the newly named taxa. A key is provided to the species of Memecylon sect. Afzeliana.  相似文献   

15.
Dendrobium sect. Dendrocoryne is a difficult taxonomic group of allied species and species complexes, occurring on the eastern Australian coastline, Lord Howe Island and New Caledonia. Significant morphological characters were assessed from all key areas of the distribution range. Patterns of variation between species, varieties and hybrids were investigated by principal coordinate analysis. The analyses affirm 12 species in the sect. Dendrocoryne described by Schlechter (1912, 1982) and Dockrill (1969, 1992), including a cluster of small statured D. gracilicaule, D. adae, D. fleckeri, and D. finniganense, and three variable species complexes – D. speciosum, D. kingianum and D. tetragonum. Recently described D. finniganense and D. callitrophilum are interpreted as members of the section. Phylogenetic relationships are presented based on parsimony analysis of 31 morphological characters. Analyses do not support proposals to recognize new genera for D. tetragonum, D. callitrophilum and D. aemulum, or to create new species within D. tetragonum, D. jonesii, D. speciosum and D. kingianum. The phylogeny indicates that rainforest taxa are earlier lineages and xerophytic taxa are more derived.  相似文献   

16.
Allium purpureoviride M. Koyuncu & ?. Genç (sect. Melanocrommyum) is described as a new species from east Anatolia, Turkey. The new species is closely related to A. rothii Zucc. from Israel and some characters of the new taxon show similarity with A. cyrilli Ten. and A. asclepiadeum Bornm. The morphological characters of the related taxa are discussed and the distribution of the taxa is mapped. The diploid chromosome number is 2n = 16.  相似文献   

17.
Advances in DNA extraction and next‐generation sequencing have made a vast number of historical herbarium specimens available for genomic investigation. These specimens contain not only genomic information from the individual plants themselves, but also from associated microorganisms such as bacteria and fungi. These microorganisms may have colonized the living plant (e.g., pathogens or host‐associated commensal taxa) or may result from postmortem colonization that may include decomposition processes or contamination during sample handling. Here we characterize the metagenomic profile from shotgun sequencing data from herbarium specimens of two widespread plant species (Ambrosia artemisiifolia and Arabidopsis thaliana) collected up to 180 years ago. We used blast searching in combination with megan and were able to infer the metagenomic community even from the oldest herbarium sample. Through comparison with contemporary plant collections, we identify three microbial species that are nearly exclusive to herbarium specimens, including the fungus Alternaria alternata, which can comprise up to 7% of the total sequencing reads. This species probably colonizes the herbarium specimens during preparation for mounting or during storage. By removing the probable contaminating taxa, we observe a temporal shift in the metagenomic composition of the invasive weed Am. artemisiifolia. Our findings demonstrate that it is generally possible to use herbarium specimens for metagenomic analyses, but that the results should be treated with caution, as some of the identified species may be herbarium contaminants rather than representing the natural metagenomic community of the host plant.  相似文献   

18.
Ariid monophyly and intrafamilial relationships are investigated based on cladistic analysis of 230 morphological characters. Terminal taxa examined include whenever possible type‐species, or the most morphologically similar species to the type‐species of the nominal genera, and the largest possible number of species, including cleared and stained specimens, available in zoological collections. Previous hypotheses about monophyly of the Ariidae are strongly corroborated by new synapomorphies discovered in the present study. The subfamily Galeichthyinae and the remaining ariids are strongly supported by new morphological characters. The monotypic subfamily Bagreinae is recognized as the sister group to all nongaleichthyin ariids, supported by a large series of exclusive synapomorphies. A new concept of Ariinae is presented: the subfamily is found to be unequivocally monophyletic and includes all ariid genera, except Galeichthys and Bagre. New data supporting the monophyly of the genera included in the Ariinae are introduced and previous hypotheses of monophyly, species composition, morphological definition, and relationships are reviewed and discussed.  相似文献   

19.
Names of 20 presumed taxa in Draba sect. Aizopsis, all based on material from Italy, are considered. Full synonymies are provided, and types are designated (for 14 names) or indicated. Most of the taxa are currently considered unworthy of recognition, of which 16 belong to D. aspera sensu lato. However, the question of whether the Sicilian populations might be distinct from the peninsular populations is still unsettled.  相似文献   

20.
There have been few studies on the taxonomy and biodiversity of the genus Lentinus in Thailand, which is a genus of edible mushrooms. Recently, collections from 17 sites in northern Thailand yielded 47 specimens of Lentinus sensu lato. Three were shown to be new species of Lentinus sensu stricto and Lentinus roseus, L. concentricus and L. megacystidiatus are introduced in this paper. The new species are described and illustrated with line drawings and are justified and compared with similar taxa. Furthermore, ITS sequence data do not match closely with any species presently lodged in GenBank.  相似文献   

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