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1.
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Numerical classification of the tribe Klebsielleae   总被引:13,自引:0,他引:13  
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3.
Koste  W.  Shiel  R. J. 《Hydrobiologia》1989,(1):279-284
Classical rotifer taxonomy and recent approaches are reviewed. -taxonomy (morphology) remains the most widely-used technique, and most prone to subjective errors. Computer technology, and genetic or biochemical methods are not widely available in areas of most need — those with developing limnology programs. Strict adherence to the International Code of Zoological Nomenclature, uniform treatment of ecotypic variation and polymorphism, communication with and between systematists, and establishment of a centralized data base are among the points discussed. A standardized nomenclature is proposed.  相似文献   

4.
A modern system of Fusarium taxonomy   总被引:1,自引:1,他引:0  
A. Z. Joffe 《Mycopathologia》1974,53(1-4):201-228
A modern system of Fusarium taxonomy is proposed, based on the study over 30 years, of the morphology and growth characteristics of fungi of this genus, and their variability under a wide range of conditions. The system proposed here comprises 13 sections, 33 species and 14 varieties. It differs from systems published by other authors mainly in the sections Eupionnotes, Sporotrichiella, Arthrosporiella, Gibbosum, Discolor, Macroconia and Martiella.  相似文献   

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Background  

Rodents are recognized as hosts for at least 60 zoonotic diseases and may represent a serious threat for human health. In the context of global environmental changes and increasing mobility of humans and animals, contacts between pathogens and potential animal hosts and vectors are modified, amplifying the risk of disease emergence. An accurate identification of each rodent at a specific level is needed in order to understand their implications in the transmission of diseases. Among the Muridae, the Rattini tribe encompasses 167 species inhabiting South East Asia, a hotspot of both biodiversity and emerging and re-emerging diseases. The region faces growing economical development that affects habitats, biodiversity and health. Rat species have been demonstrated as significant hosts of pathogens but are still difficult to recognize at a specific level using morphological criteria. DNA-barcoding methods appear as accurate tools for rat species identification but their use is hampered by the need of reliable identification of reference specimens. In this study, we explore and highlight the limits of the current taxonomy of the Rattini tribe.  相似文献   

7.
The results of a comparative survey on pollen morphology in theBoragineae by means of light, scanning and transmission electron microscopy are presented and discussed in relation to the taxonomy of the tribe. Multivariate analyses lead to the recognition of 15 pollen morphotypes for which a discriminant key is proposed. The discriminatory characters concern mainly the stereostructural and ultrastructural features of the grains, such as tectum sculpture and aperture morphology, while the number of apertures appears variable within genera and even single species. Seven out of the 12 investigated genera, as currently circumscribed, are matched by palynological data:Anchusella, Borago, Brunnera, Elizaldia, Lithodora, Symphytum andTrachystemon. On account of aperture shape,Lithodora is however closer to theLithospermeae than to theBoragineae. Other genera, and in particularNonea, show a wide variation in tectum ornamentation, shape of grains and number of apertures. Palynological data do not support a broad concept of the genusAnchusa, and point to the autonomy of the satellite generaHormuzakia, Gastrocotyle, Phyllocara, Pentaglottis andCynoglottis.  相似文献   

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9.
Three South African species of digger wasps of the tribe Oxybelini, initially described in the genus Belomicrus A. Costa, B. (Nototis) bicornutus Arnold, B. (Nototis) crassus Arnold, and B. ferrieri Kohl, are considered to be members of the separate genera Nototis Arnold, 1927, Belarnoldus gen. n., and Belokohlus gen. n., respectively. The new species Nototis falcidens and the previously unknown male of N. bicornutus and female of B. crassus are described. The lectotype of B. ferrieri is designated.  相似文献   

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This study is an attempt to understand the physical growth and nutritional status of Bharia, a primitive tribe of Central India. A cross sectional study was conducted on 551 children (283 boys and 268 girls) aged 4 to 18 years. Body weight, height, sitting height, head circumference, upper arm circumference, chest circumference, biceps, triceps, sub scapular and calf skin fold thickness were measured. Body Mass Index was calculated as weight/height2 to calculate chronic energy deficiency. All anthropometric measurements except skin fold measurement exhibit uniform increase with age in both the sexes. Age-specific Body Mass Index (BMI) indicated substantial changes and falls during pre-school age and rise in adolescence. The BMI according to the Indian standard was normal, but when the data was compared with the International standard malnutrition in both sexes was noticed in childhood. Boys remained undernourished after adolescence, while girls reached the normal growth patterns.  相似文献   

12.
梭菌属分类研究进展:现状和展望   总被引:2,自引:0,他引:2  
目前构成梭菌属的微生物在系统发育和表型特征上不一致。多相分类数据表明,梭菌属物种之间差异大。大量基于16S rRNA 基因的系统发育研究表明,梭菌属应被限定为梭菌属类群I,作为狭义梭菌属(Clostridium sensu stricto)。尽管有这方面认识,梭菌属新物种仍持续增加,这些新物种并不能与梭菌属类群I 和标准种丁酸梭菌(C. butryicum)形成一致分支,引发梭菌属分类上的混乱。本文明确了梭菌属物种的范围,即只包括模式种和梭菌属类群I。此外,4 个物种念珠状真杆菌(Eubacterium moniliforme)、旋舞真杆菌(Eubacterium tarantellae)、最大八叠球菌(Sarcina maxima)和胃八叠球菌(Sarcina ventriculi)应被调至梭菌属,分别命名为念珠状梭菌(Clostridium moniliforme)、旋舞梭菌(Clostridium tarantellae)、最大梭菌(Clostridium maximum)和胃梭菌(Clostridium ventriculi)。一个新属哈撒韦氏菌属(Hathewaya)被提议成立,3 个梭菌属物种溶组织梭菌(Clostridium histolyticum)、泥渣梭菌(Clostridium limosum)和解朊梭菌(Clostridiumproteolyticum)重新归为溶组织哈撒韦氏菌(Hathewaya histolytica)、泥渣哈撒韦氏菌(Hathewaya limosa)和解朊哈撒韦氏菌(Hathewaya proteolytica),其中Hathewaya histolytica 为模式种。  相似文献   

13.
The modern Sirenia have been little studied because of their present rarity and the difficulty of observing fully aquatic animals even though so large. These mammals are the only large aquatic herbivores. One of the three modern forms, Steller's seacow, is recently extinct; the dugong of the tropical Indo-Pacific region is now rare almost everywhere apart from some of the northern waters of Australia, while the manatee of the two sides of the tropical Atlantic is both marine and riverine but has become very scarce.
The two authors have, over 12 years, endeavoured by means of personal visits to the Guianas, Australia, Torres Strait, Ceylon and elsewhere, and by copious correspondence, to gather material so as to summarize the present distribution and status of the Sirenia. This information is presented in a setting of conservation and eventual rational use as meat animals and in other ways. There is also reference to the history and manner of exploitation which has brought the Sirenia to their present lowly state. The main residual stock is that in northernmost Australian waters, and there numbers may now indeed begin again to increase.  相似文献   

14.
The pest termites of South America: taxonomy, distribution and status   总被引:3,自引:0,他引:3  
Abstract: A total of 77 species of termites have been reported as structural or agricultural pests in South America. These records are reviewed, with indication of the damage they cause, their pest status, distribution and sources of information. Among these, 40 species are reported as structural pests, 53 species as agricultural pests and 15 species as both. However, only 18 species are considered major pests and the status of most of the others is uncertain. Uncertainty about status is much higher among agricultural pests. Specific taxonomic problems are discussed and distribution maps of the main pest genera and species are presented. The most important structural pests are the introduced Coptotermes havilandi and Cryptotermes brevis and the native Nasutitermes corniger. Reticulitermes was introduced into Uruguay and Chile, where it is the only serious pest. The main agricultural pests are Heterotermes spp., Nasutitermes spp., Cornitermes spp., Procornitermes spp. and Syntermes spp., and the most affected crops are sugarcane, upland rice and eucalyptus.  相似文献   

15.
Previous studies from this laboratory have documented the presence of coliform bacteria emanating from wooden reservoirs containing finished drinking water. Coliforms were identified as Klebsiella pneumoniae and Enterobacter spp. In the present report, evidence is presented which suggests that the origin of these coliforms is from the wood used to construct the reservoirs. In liquid expressed from freshly cut redwood, total bacterial counts in the range of 10(5) to 10(6)/ml were commonly observed. When present, coliform counts were over 10(3)/ml of expressed liquid. E. agglomerans was the most prevalent coliform present, but Klebsiella was isolated from freshly cut logs. Citrobacter freundii was also occasionally isolated. No fecal coliform-positive Klebsiella were obtained from any of the samples. Highest total bacteria and coliform counts were observed in sapwood specimens. Coliforms were present throughout sapwood as evidenced by contact plating serial sections of freshly cut wood. Scanning electron micrographs illustrate the presence of bacterial colonies within sapwood tracheids. Other wood species also contained coliform bacteria but in numbers lower than found in redwood.  相似文献   

16.
Summary A discussion covering the problems ofFrankia taxonomy was held at the Frankia Workshop in Wageningen, September 4–6, 1983. It was agreed that the genusFrankia can be satisfactorily defined, but that solid criteria for species determination are not now available and that use of specific names should be avoided for the present.  相似文献   

17.
Bacteria of the tribe Klebsielleae are capable of metabolizing the cyclitols myoinositol, sequoyitol, and pinitol, which are present in aqueous extracts of redwood. Of the combined Klebsiella isolates from clinical and environmental origins, 100% (138/138), 97% (34/35), and 86% (119/138) fermented inositol, sequoyitol, and pinitol, respectively. These compounds were also used as a sole source of carbon and energy by Klebsiella. Similar results were obtained with Enterobacter isolates, but most other enteric bacteria tested could not metabolize cyclitols. Strains of Klebsiella multiplied to levels exceeding 10(5)/ml in aqueous extracts of nonsterile redwood within 6 days. Most other enteric bacteria did not grow in these extracts. Cyclitol metabolism was found to correlate well with the ability to multiply in redwood extract in the presence of cyclitol-negative indigenous bacteria. The capacity to use cyclitols, which are present in a variety of plant material, might afford Klebsielleae of both environmental and clinical origins an advantage in competing for nutrients and colonizing botanical environments.  相似文献   

18.
19.
Isolation of Klebsielleae from within living wood.   总被引:1,自引:5,他引:1       下载免费PDF全文
Previous studies from this laboratory have documented the presence of coliform bacteria emanating from wooden reservoirs containing finished drinking water. Coliforms were identified as Klebsiella pneumoniae and Enterobacter spp. In the present report, evidence is presented which suggests that the origin of these coliforms is from the wood used to construct the reservoirs. In liquid expressed from freshly cut redwood, total bacterial counts in the range of 10(5) to 10(6)/ml were commonly observed. When present, coliform counts were over 10(3)/ml of expressed liquid. E. agglomerans was the most prevalent coliform present, but Klebsiella was isolated from freshly cut logs. Citrobacter freundii was also occasionally isolated. No fecal coliform-positive Klebsiella were obtained from any of the samples. Highest total bacteria and coliform counts were observed in sapwood specimens. Coliforms were present throughout sapwood as evidenced by contact plating serial sections of freshly cut wood. Scanning electron micrographs illustrate the presence of bacterial colonies within sapwood tracheids. Other wood species also contained coliform bacteria but in numbers lower than found in redwood.  相似文献   

20.
《Fungal biology》2020,124(10):835-844
This paper presents the reinterpretation of the taxonomic position of fossil epiphyllous callimothalloid fungi belonging to the fossil-genera Callimothallus (hitherto classified to the family Microthyriaceae) and Cribrites (?Microthyriales). These fungi thrived from the Late Cretaceous up to the Holocene. Investigation are based on collected material from the Oligocene of Hungary and the Miocene of Poland and on published data. For the common callimothalloid fungus Callimothallus pertusus, a new combination Neomycoleptodiscus pertusus is proposed. Callimothallus quilonensis is assigned to a new fossil-genus Muyocopromyces as a new combination Muyocopromyces quilonensis. We reconsider the fossil-species Ratnagiriathyrites hexagonalis as a younger synonym of the fossil-genus Cribrites. The geographical range of fossil callimothalloid fungi and their recent counterparts are discussed. Fossil Neomycoleptodiscus, Muyocopromyces, and Cribrites are proposed as reliable climate proxy of warm climate conditions in the past.  相似文献   

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