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1.
Kuehn  Harold H.  Orr  G. F.  Ghosh  G. R. 《Mycopathologia》1964,23(1):29-35
Summary A new species ofPetalosporus, P. anodosus, is described and illustrated. Two isolates representing this species were isolated from dung in California. The new species differs from the only other species of the genus,P. nodulosus, by the lack of thick-walled peridial hyphae with enlargements at the septa and by the absence of disarticulation of peridial elements. Peridial hyphae inP. anodosus have walls which are somewhat thickened and the cells are often variable in diameter. Conglomerate ascospores usually assume the petaloid arrangement characteristic of the genus.  相似文献   

2.
A comparison of methods for mapping species ranges and species richness   总被引:5,自引:0,他引:5  
Aim  Maps of species richness are the basis for applied research and conservation planning as well as for theoretical research investigating patterns of richness and the processes shaping these patterns. The method used to create a richness map could influence the results of such studies, but differences between these methods have been insufficiently evaluated. We investigate how different methods of mapping species ranges can influence patterns of richness, at three spatial resolutions.
Location  California, USA.
Methods  We created richness maps by overlaying individual species range maps for terrestrial amphibians and reptiles. The methods we used to create ranges included: point-to-grid maps, obtained by overlaying point observations of species occurrences with a grid and determining presence or absence for each cell; expert-drawn maps; and maps obtained through species distribution modelling. We also used a hybrid method that incorporated data from all three methods. We assessed the correlation and similarity of the spatial patterns of richness maps created with each of these four methods at three different resolutions.
Results  Richness maps created with different methods were more correlated at lower spatial resolutions than at higher resolutions. At all resolutions, point-to-grid richness maps estimated the lowest species richness and those derived from species distribution models the highest. Expert-drawn maps and hybrid maps showed intermediate levels of richness but had different spatial patterns of species richness from those derived with the other methods.
Main conclusions  Even in relatively well-studied areas such as California, different data sources can lead to rather dissimilar maps of species richness. Evaluating the strengths and weaknesses of different methods for creating a richness map can provide guidance for selecting the approach that is most appropriate for a given application and region.  相似文献   

3.
During surveys of the protostelids of the Hawaiian Islands and the South Island of New Zealand, an undescribed species of Protostelium was discovered fruiting on collections of substrates found in several sites on the southern and western parts of the island of Hawaii and from one site near Port Elizabeth, New Zealand. The new species, P. okumukumu, has a sporocarp with a bipartite stalk that supports a single, spherical spore. The basal portion of the stalk is straight and rigid. The upper part of the stalk is a nearly spherical apophysis. The junction between the stalk base and the apophysis is flexible such that the spore and apophysis swing back and forth as a unit. Spores are forcibly discharged from the stalk, and only the straight base of the stalk is left behind. Amoebae typical of the taxon Protostelium germinate from the spores, and when an amoeba differentiates into a prespore cell, it becomes lozenge shaped (nearly ellipsoid) in top view, as is typical for species of Protostelium. This represents the seventh species of protostelids described to have forcible spore discharge, and the possibility of forcible discharge needs to be examined in several other species.  相似文献   

4.
Summary A new species of Volvulina, V. pringsheimii, was isolated from Texas. This species differs from the well-known species of Volvulina, V. steinii, in having pyrenoids in the vegetative cells, a common gelatinous envelope surrounding the colony, a protoplasmic protrusion on the anterior end of each gamete, and spines on the secondary wall of the zygospore.This paper is dedicated to Professor Dr. E. G. Pringsheim on the occasion of his 80th birthday.  相似文献   

5.
Question: The prominent role of wind dispersal in alpine habitats has been recognized early but has rarely been quantified. The aim of this study is to compare wind dispersal under alpine and lowland conditions and to analyse whether differences are caused by species traits, e.g. terminal velocity of seeds (Vterm) or weather conditions. Location and Methods: We characterized wind dispersal potential of > 1100 Central European species using measured Vterm To quantify the habitat effect on wind dispersal, we measured meteorological key‐parameters and simulated dispersal distance spectra of nine selected species under typical alpine conditions (foreland of the Scaletta‐glacier, Switzerland) and typical lowland conditions (grassland in Bad Lippspringe, Germany). Results: Lowland species had higher Vterm compared to alpine species. However, this difference is absent when only species of species of open habitats are concerned. The meteorological measurements showed that the alpine habitat was mainly characterized by higher frequency and strength of updrafts. The simulations showed that under alpine conditions long distance dispersal occurred much more frequent. Conclusions: More than 50 % of the alpine species have a fair chance to be dispersed by wind over long distances, while this proportion is less than 25 % for species from open habitats in the lowland. The more prominent role of wind dispersal in alpine habitats is mainly a result of differences in environmental conditions, namely more intense vertical turbulence in the alpine habitat, and does not result from prominent differences in plant traits, namely Vterm, between alpine and lowland species.  相似文献   

6.
Somrithipol S 《Mycologia》2007,99(5):792-796
Genus Dictyoarthrinium is reviewed. Dictyoarthrinium synnematicum, collected on decaying banana leaves in Thailand, is illustrated, described as a new species and compared with related taxa. The fungus differs from other Dictyoarthrinium species in having a synnematous structure. This species is the first synnematous record of an anamorphic fungus with basauxic conidiophores. A key to species of Dictyoarthrinium is provided.  相似文献   

7.
Abstract. A new species of Aphis, A, comari spm., is described from shoots and leaves of Potentilla (Comarum) palustris (L.) Scop. in England and Wales. Its biology and relationship to previously described species of Aphis L. from Potentilla species and Sanguisorba minor Scop. are discussed.  相似文献   

8.
Lasiobolidium gracile isolated from a soil sample collected from California, USA is described as a new species. This species is characterized by yellowish brown to reddish brown, nonostiolate ascomata with numerous, long straight appendages and a translucent peridium, subglobose to broadly clavate asci, hyaline to pale yellowish brown, ellipsoidal ascospores. It differs from the other species ofLasiobolidium in the straight and narrow appendages and the large ascospores. A key is presented separating the seven known species.  相似文献   

9.
10.
An investigation has been made of the relation between species diversity and the lognormal distribution of individuals among species, using phytoplankton samples from the Indian Ocean. The area under the truncated lognormal curve representing a sample gives the total number of species, S, while the logarithmic standard deviation, σ, gives a measure of the scatter of distribution of individuals among species, the other factor affecting diversity. Using a method described by Hald, truncated lognormal curves were fitted to the phytoplankton data and estimates obtained for the mean, ξ, the logarithmic standard deviation, σ, the number of species in the modal octave, No, and the number of species in the population universe, N. Since one is interested in a sample only in so far as it reflects the properties of the population from whence it came, estimated population parameters were used to define measures of diversity by which means it was hoped to obtain a diversity index independent of sample size, i.e., a diversity value related more to the population than to the sample.  相似文献   

11.
A new yeast species,Bullera piricola, is described. The three strains studied were all isolated from the pear phylloplane. This species differs from allBullera species known at present by forming symmetrical as well as asymmetrical ballistospores. The problem of its integration into the genusBullera Derx is discussed. An amended diagnosis of the genusBullera is given. A preliminary publication based on a doctoral thesis, being preparared under the direction of Prof. Dr. F. J. Schwinn.  相似文献   

12.
《Journal of bryology》2013,35(3):343-351
Abstract

A new species (Brachydontium intermedium) is described. It is the first record of the genus for Australia and a comparison is made with the other two species, both from the Northern hemisphere.  相似文献   

13.
Psychrolutes occidentalis, a new species of psychrolutid fish, is described from mud bottoms at depths of 350–740 m on the continental slopes around Rowley Shoals, northwestern Australia. The new species is illustrated and compared with other species of the genusPsychrolutes. It differs from other species in the following characters: 14–15 dorsal soft rays, 21–23 pectoral rays, 30–31 vertebrae, no cirri on head and body, lateral line not emerging through tubes, and reddish brown head and body color with darker brown marblings. Aspects of the zoogeography of this new species from the tropical region and of the other species ofPsychrolutes are discussed.  相似文献   

14.
In conservation planning, species richness and species endemism are the most often used metrics for describing the biodiversity importance of areas. However, when it comes to prioritizing regions for conservation actions these measures alone are insufficient because they do not reveal how similar or different the actual composition of species may be from one area to another. For comparative analysis an additional useful metric would be one that indicates the degree to which the species assemblage in one area is also represented in—or is distinct from—species assemblages of other areas. Here we describe a method for quantifying the compositional representativeness of species assemblages among geographic regions. The method generates asymmetric pairwise similarity coefficients that are then used to calculate separate measures for the representativeness and the distinctiveness of species assemblages in the regions being compared. We demonstrate the method by comparing fish communities among freshwater ecoregions of the Mississippi Basin, and then among smaller hydrological units within two individual freshwater ecoregions. At both scales of analysis, our measures of representativeness and distinctiveness reveal patterns of fish species composition that differ from patterns of species richness. This information can enhance conservation planning processes by ensuring that priority-setting explicitly consider the most representative and distinctive species assemblages.  相似文献   

15.
Questions: Is it possible to render the species pool concept operational for cultural landscape management and restoration? Location: Hordaland and Sogn & Fjordane counties, western Norway. Methods: An initial regional species list, based on information on the distribution of species and habitats in the Norwegian flora, was filtered using information on target communities and species lists from 95 sites in the region. Owing to the importance of both mowing and grazing Ellenberg indicator values were not used in the identification process. Results: The final regional species pool consisted of 227 species, of which 194 were extracted from the flora, while 33 agricultural landscape species were added from the actual pool or from a list of species in additional hay meadows. Some of the 33 species were regular inhabitants of hay meadows, others were rare in the region. The regional species pool list includes information on each species on demands when hydrology, nutrients and base saturation in the soil is concerned, and whether or not they are characteristic for either of the boreal or boreo‐nemoral vegetation zones. Conclusions: Specialist knowledge was an advantage when adding cultural landscape species other than meadow species of the flora; 77 species were documented only by the flora, interesting from the point of view of restoration as this part of the pool would not have been found by just adding species lists. The diversity of the now isolated hay meadow sites in the region may be kept up by replacing the lost natural invasion by an artificial one, using local seed mixtures and transplants.  相似文献   

16.
One hundred and thirty-six years since On the Origin of Species 3., biologists might be expected to have an accepted theory of speciation. Instead, there is, if anything, more disagreement about speciation than ever before. Even more surprisingly, 60 years after the biological species concept, in which species were considered to be reproductive communities isolated from other such communities, we still do not all accept a common definition of what a species is. And yet, if speciation is to be any different from ordinary evolution, we must have a clear definition of species. The emerging solution to the species problem is an updated, genetic version of Darwin's own definition. This definition is useful and is already being used in taxonomy, in biodiversity studies and in evolution.  相似文献   

17.
Anthopsis catenata sp. nov., isolated from roots of Abies alba is described. The species is characterised by inverted phialides producing pale brown, ellipsoidal to subglobose conidia in chains.  相似文献   

18.
Narendra  D. V.  Rao  V. G. 《Mycopathologia》1974,54(1):135-140
Mycopathologia - A new entomogenous species ofPhoma, P. aspidioticola, has been described on a scale insect (Aspidiotus destructor Sign.) from India on the basis of morphological characters and...  相似文献   

19.
A new species of Lens from south-east Turkey   总被引:1,自引:0,他引:1  
A new species of Lens (Leguminosae), L. tomentosus , is described. It resembles L. culinaris except in its tomentose pods. Karyotypically it differs from other Lens species by the satellited chromosome which is much smaller, extremely asymmetrical and bears a minute satellite. Lens tomentosus is reproductively isolated from all other Lens species. Hybrids cannot be obtained because of embryo abortion, and irregular meiosis in hybrids raised via embryo culture. Currently, three populations of L. tomentosus are known in the Mardin area, south-east Turkey.  相似文献   

20.
A new species of Phylloscopus warbler from central China   总被引:7,自引:0,他引:7  
A new species of leaf warbler (Sylviidae: Phylloscopus) is described from the mountains of central China. Morphologically it is slightly, yet significantly, different from the partly sympatric P. (proregulus) chloronotus. However, both song and calls are very different, and playback tests elicited no response from either species to the other's song. There are also differences in habitat preference and breeding biology of the two species.  相似文献   

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