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1.
Callinera monensis sp. n., from Derbyhaven Harbour in the Islc of Man, is described and illustrated. The anatomy of the species is compared and contrasted with that of the other known members of the genus, Callinera buergeri Bcrgcndal and C. buergeri f. grandis Bergendal, from Scandinavian waters; f. grandis is afforded separate specific status as C. grandis Bcrgcndal.  相似文献   

2.
ABSTRACT The morphology of the hypotrichous ciliate, Holosticha corlissi n. sp., found in the moss Calliergonella cuspidata taken from the beech wood of Montejo de la Sierra (Madrid, Spain) is described. Some characteristics (organization of the mid-ventral, frontal and fronto-terminal cirri, presence of a buccal cirrus and the number of transverse cirri) are sufficiently different from the closely related species H. intermedia, H. sigmoidea and H. xanthichroma to suggest that it is a separate species, although its body shape, nucleus and buccal apparatus are very similar.  相似文献   

3.
Abstract:Two new species of lichens are described from the Iberian Peninsula. Halecania giraltiae is the first sorediate saxicolous species known in the genus and has been collected growing on lichens and sometimes directly on rock in localities from northern Portugal to central Spain. Catillaria fungoides, a sorediate, corticolous representative of the C. nigroclavata group, is known from southern Portugal and northern Spain.  相似文献   

4.
The breeding ecology of White and Japanese Wagtails, Motacilla alba and M. grandis , was studied along a river in central Japan. The home ranges of the two species greatly overlapped along the river, but no interbreeding occurred. M. grandis spent more time on the river than M. alba and defended territories there. M. alba used the river as part of the entire home range, and did not defend the river areas as territories. Singing activity and breeding started earlier in M. grandis than in M. alba. The early breeding of M. grandis was related to the lack of moulting in spring, less necessity for pair formation due to the existence of pairs in the winter, and the greater dependency on larval than on adult insects. Songs were very different between the two species. The bowing display that preceded the pre-copulation display was found only in M. alba. During the pre-copulation display, male M. grandis lifted both wings above the horizontal while male M. alba drooped both wings. The pre-copulation display of M. grandis was similar to that of Large Pied Wagtails M. maderaspatensis in India, suggesting a closer relationship of the two species than to M. alba.  相似文献   

5.
Hamill RM  Doyle D  Duke EJ 《Heredity》2006,97(5):355-365
Fossil evidence shows that populations of species that currently inhabit arctic and boreal regions were not isolated in refugia during glacial periods, but instead maintained populations across large areas of central Europe. These species commonly display little reduction in genetic diversity in northern areas of their range, in contrast to many temperate species. The mountain hare currently inhabits both temperate and arctic-boreal regions. We used nuclear microsatellite and mtDNA sequence data to examine population structure and alternate phylogeographic hypotheses for the mountain hare, that is, temperate type (lower genetic diversity in northern areas) and arctic-boreal type (high northern genetic diversity). Both data sets revealed concordant patterns. Highest allelic richness, expected heterozygosity and mtDNA haplotype diversity were identified in the most northerly subspecies, indicating that this species more closely maps to phylogeographic patterns observed in arctic-boreal rather than temperate species. With regard to population structure, the Alpine and Fennoscandian subspecies were most genetically similar (F(ST) approximately 0.1). These subspecies also clustered together on the mtDNA tree and were assigned with highest likelihood to a common Bayesian cluster. This is consistent with fossil evidence for intermediate populations in the central European plain, persisting well into the postglacial period. In contrast, the geographically close Scottish and Irish populations occupied separate Bayesian clusters, distinct clades on the mtDNA maximum likelihood tree and were genetically divergent from each other (F(ST) > 0.4) indicating the influence of genetic drift, long isolation (possibly dating from the late glacial era) and/or separate postglacial colonisation routes.  相似文献   

6.
A new species of Deinsdorfia is defined using new material coming from the karstic fissure infilling of Almenara-Casablanca 4 (Castelló, Spain), which shows important differences with the rest of the previously known species of the genus. The definition of a new species is supported by the characters found in extra material coming from the localities of Valdeganga, in the Albacete Province (Spain). The stratigraphical occurrence of this genus of pigmented-toothed shrews reinforces the idea of the Iberian Peninsula as a sink area during the Pliocene, where some Central-European soricids expanded their distribution. Most of those migrations or distributional expansions coincide with moments of climatic changes in the northern hemisphere.  相似文献   

7.
A preliminary study to characterize filamentous bacteria, whose presence is related to high mortality of Litopenaeus vannamei larvae cultured in Santa Catarina State, Brazil, is reported. The extract of infected larvae was diluted in different concentrations, cultured in marine agar (Difco, Marine Agar 2216) and incubated at 30 degrees C for 48 hours. The biochemical characterization included hydrolytic reactions of starch, gelatin and tyrosine, growth in TCBS agar, growth in 0 and 37 per thousand salinity, pigment production in tyrosine agar, production of H2S, nitrate reduction, congo red reaction, oxidase and catalase. The isolated bacteria belong to the species Flexibacter maritimus, Gram-negative bacilli of 0.4-0.5 microm width and 15 microm length. Experiments were carried out on pathogenicity of F. maritimus in post-larvae of L. vannamei. Survival and symptoms in L. vannamei post-larvae 24 hours after inoculation with F. maritimus and its growth in marine agar were evaluated. Mortality was detected around 92,5% as well as symptoms like melanized lesions in several parts of body, discolouration of gills, bad formation of appendages and of the last abdominal segment, low motility and feeding reduction. The experimental infection results suggested that isolated bacteria of the genus Flexibacter are pathogenic to the shrimp Litopenaeus vannamei post-larvae.  相似文献   

8.
Aim To locate glacial refugia of thermophilous plant species in Spain. Location Two south‐eastern Spanish Neanderthal man sites in Murcia; namely, the inland Cueva Negra del Estrecho del Río Quípar and the coastal Sima de las Palomas del Cabezo Gordo. Methods We use pollen found in cave sediments as a source of palaeobotanical and palaeoecological information. The findings are discussed with regard both to animal remains from both sites, and also to other refugia in south‐eastern Spain and elsewhere in the Iberian Peninsula. Results Both sequences show persistence of abundant mesothermophilous trees during the last glacial stage, suggesting both localities were reservoirs of phytodiversity and woodland species. At both sites, deciduous and evergreen oaks are the most abundant components, followed by a wide variety of deciduous trees and sclerophyllous shrubs, including Ibero‐North African xerothermic scrub near the coast. Conclusions Incomplete information underlies a common misapprehension that Iberian glacial refugia were confined to southernmost parts of the peninsula. A rather different picture of Quaternary refugia emerges from consideration of pollen sequences from caves (and other inputs such as macroscopic charcoal, spatial genetic structure of present‐day populations, faunal remains, and present‐day distribution of thermophilous species). This picture offers a view of numerous viable areas for woodland species in southern Spain, in addition to others in the mountain ranges, both in continental central Spain and those of northern Spain: these stretch from the Mediterranean coast of Catalonia to the westernmost extent of the Bay of Biscay.  相似文献   

9.
The present paper is an attempt to propose a preliminary taxomomic treatment of the genus Hippolytia Poljak. and to analyse the geographical distribution of its composite elements. This small genus with 17 species is divided into 2 sections, namely, section Anthodesma Shih and section Hippolytia. Anthodesma is a small section with 3 species and is characterized by fascicled corymbs, campanulate and nitid involucres, rigidly herbaceous phyllaries, and undershrubs, while Hippolytia consisting of 14 species is characterized by corymbose inflorescence or glomerules or compund heads, cuneate and unpolished involucres, herbaceous phyllaries with pitch black margines. There are 12 species of Hippolytia in China, of which 3 are proposed as new in the present paper. Regarding the distribution pattern of Hippolytia, it is noteworthy to note that its range of distribution forms a more or less U-shape as shown in map 2. It may be seen that Hippolytia distributes in Central Asia-Sino-Himalaya-Median Asia. Section Anthodesma Shih occurs in central Asia, while section Hippolytia in the whole Himalayan region and northern Meridional Ranges and Median Asia. There seems to be no center of species concentration within the total range of Hippolytia, whose species are localized in distribution, for example, H. desmantha Shih is known only from Qinghai provence (Yu-Shu-Hsien), H. alashanensis (Ling) Shih is restricted to Ninghsia and central part of Kansu provence. It is interesting to note that H. yunnanensis (J. F. Jeffrey) Shih and H. longifolia (Wall.) Shih are referred to as vicarious species. The localization of the species distribution and the obvious discontinuity of morphological characters between species indicate a remarkable geographical influence on the species formation of Hippolytia. Hippolytia is an alpine genus of temperate zone of Asia, in which 64 per cent of species occurs at high elevations of above 3300m. altitude, 30 per cent of species are distributed in middle elevations of above 2200m. altitude. The life forms are microundershrubs, erect perennial herbs, glomerule stemless herbs or stemless herbs. It is very possible that its geographical origin and development may be linked up with occurance of desert steppe, especially of alpine meadow vegetations in the northern temperate zone of Asia. With regard to the geographical elements to which each species of Hippolytia belongs, it seems to indicate that H. trifida (Turcz.) Poljak., H. alashanensis (Ling) Shih and H. desmantha Shih belong to the geographical elements of central Asia, while H. yunnanensis (J. F. Jeffrey) Shih, H. glomerata Shih, H. tomentosa (DC.) Tzvel., H. senecionis (Bess.) Poljak. H. longifolia (Wall.) Shih, H. kennedayi (Dunn) Ling, H. syncalathiformis Shih, H. gossypina (Hook. f. et Thoms.) Shih and H. nana (C. B. Clarke) Shih to Himalayan elements, and H. darvasica (C. Winkl.) Poljak., H. megacephala (Rupr.) Poljak,, H. herderi (Rgl. et Schmalh.) Poljak. to Median Asia, H. delavayi (W. W. Smith) Shih to North-West-Yunna.  相似文献   

10.
Selected,little known taxa of northern and central Vietnamese freshwater fish species are reviewed.Nomenclatural acts are taken:Hemibarbus lehoai is placed in synonymy of H.maculatus,Paracobitis hagiangensis in synonymy of Schistura caudofurca.A neotype of Micronemacheilus bacmeensis is assigned.The name Channa hanamensis is treated as a nomen nudum.Two labeonine species described from China are nomenclaturally affected:Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition;the specific epithet of Sinigarra napoense is corrected to napoensis.  相似文献   

11.
Aims Osmolytes, used for maintaining osmotic balance and as 'osmoprotectants', are synthesized in plants as a general, conserved response to abiotic stress, although their contribution to stress-tolerance mechanisms remains unclear. Proline, the most common osmolyte, accumulates in many plant species in parallel with increased external salinity and is considered a reliable biochemical marker of salt stress. We have measured proline levels in two halophytic, closely related Juncus species under laboratory and field conditions to assess the possible relevance of proline biosynthesis for salt tolerance and therefore for the ecology of these two taxa.Methods Proline was quantified in plants treated with increasing NaCl concentrations and in plants sampled in two salt marshes located in the provinces of Valencia and Alicante, respectively, in southeast Spain. Electrical conductivity, pH, Na + and Cl ? concentrations were measured in soil samples collected in parallel with the plant material.Important findings Treatment with NaCl inhibited growth of J. acutus plants in a concentration-dependent manner, but only under high salt conditions for J. maritimus. Salt treatments led to proline accumulation in both species, especially in the more salt-tolerant J. maritimus. The results, obtained under laboratory conditions, were confirmed in plants sampled in the field. In all the samplings, proline contents were significantly lower in J. acutus than in the more tolerant J. maritimus growing in the same area. No direct correlation between soil salinity and proline levels could be established, but seasonal variations were detected, with increased proline contents under accentuated water deficit conditions. Our results suggest that proline biosynthesis is not only an induced, general response to salt stress but also an important contributing factor in the physiological mechanisms of salt tolerance in Juncus, and that it therefore correlates with the ecology of both species.  相似文献   

12.
13.
Thesium hispanicum is a newly described species, stenoendemic for the area of the mountains Picos de Europa in north Spain. It is the westernmost representative of the seriesMicrantha, distributed in several species from beyond Transcaucasian and Turkish Kurdistan over the whole northern portion of the Mediterranean.  相似文献   

14.
An epidemiological survey was undertaken of anisakids in 139 specimens (length: 13.2-24.5 cm) of pouting or bib (Trisopterus luscus) captured off the coast of northern Spain in the Cantabrian Sea. Third-stage larvae of two species of nematodes, Anisakis larvae type I and Hysterothylacium aduncum, were isolated. One adult female H. aduncum was also detected in the intestine of one pouting. Total prevalence of anisakids was 88.5%. Hysterothylacium aduncum and Anisakis showed, respectively, prevalence of 87.8% and 22.3%, mean intensity of 19.7 and 3.5, and mean abundance of 17.3 and 0.8. Analysis of infection parameters as a function of host length revealed a much higher prevalence in pouting specimens with length < 20 cm (94.4% for H. aduncum; 28.0% for Anisakis) than in those with length > or = 20 cm (65.6% for H. aduncum; 3.1% for Anisakis). The high mean intensity of Anisakis in muscle of parasitized pouting (5.9) may pose human health risks, although these are minimized by eating only thoroughly cooked pouting, as is the custom in Spain.  相似文献   

15.
土小平盘菌复合群原产澳大利亚,其中两个土生种在西班牙报道,很可能是在18世纪中叶引入西班牙。根据形态学特征和序列分析的结果,建立一个新组合和一个新种,分别定名为Phaeohelotium undulatum comb.nov.和Phaeoh.succineoguttulatum sp.nov.。对其宏观和微观形态特征进行了详尽的描述和图示,ITS rDNA序列分析的结果显示,它们以100%的支持率与Phaeohelotium monticola聚类在同一个分支。文中提供了该复合群Phaeohelotium属5个土生种的分种检索表,并对它们的生态习性与世界分布进行了深入讨论。  相似文献   

16.
Aim, location Tomicus (Coleoptera, Scolytidae) species are some of the principal pests of Eurasian forest and are represented by three coexisting species in Spain, Tomicus piniperda (Linnaeus, 1758), Tomicus destruens (Wollaston, 1865) and Tomicus minor (Harting, 1834). The distribution of two taxa are unknown as they have until recently been considered separate species. Therefore, we model the potential distribution centres and establish the potential distribution limits of Tomicus species in Iberia. We also assess the effectiveness of different models by comparing predicted results with observed data. These results will have application in forest pest management. Methods Molecular and morphological techniques were used to identify species from 254 specimens of 81 plots. For each plot, a Geographical Information System was used to extract a set of 14 environmental (one topographic, six climatic) and biotic variables (seven host tree distributions). General Additive Models and Ecological Niche Factor Analysis models are applied for modelling and predicting the potential distribution of the three especies of Tomicus. Results The results of both modelling methodologies are in agreement. Tomicus destruens is the predominant species in Spain, living in low and hot areas. Tomicus piniperda occurs in lower frequency and prefers wet and cold areas of north‐central Spain. We detected sympatric populations of T. destruens and T. piniperda in Northern coast of Spain, infesting mainly P. pinaster. Tomicus minor is the rarest species, and it occupies a fragmented distribution located in high and wet areas. The remarkable biotic variable is the distribution of P. sylvestris, incorporated into the models of T. destruens and T. piniperda. Main conclusions These results indicate that in wet areas of north‐central Spain where T. piniperda occurs (and possibly the high altitudes of the southern mountains), T. destruens has a climatic distribution limit. In the northern border of this area, both species overlap their distributions and some co‐occurrences were detected. Tomicus minor potentially occurs in high and wet fragmented areas.  相似文献   

17.
基于空间信息技术的香榧适生环境因子分析   总被引:3,自引:0,他引:3  
香榧系第三纪孑遗植物,为我国特有的珍贵经济树种,是我国近年来发展较快、经济效益最好的经济林树种之一.研究香榧特有的适生环境特征将为香榧的引种、扩种和区划提供理论依据,对其产业化发展和可持续利用具有重要意义.基于空间信息技术的强大功能,利用香榧核心产区——浙江省诸暨市7个村的高分辨率IKONOS遥感影像、数字高程模型(DEM)以及土壤、地质、气象和实地调查等资料,采用主成分分析方法对研究区的生境因子进行了综合分析.结果表明:研究区香榧对海拔、坡度和坡向等因子具有高度选择性;96.22%的香榧分布在海拔300~600 m的高度带上,97.52%的香榧分布在坡度<30°的坡地上,74.43%的香榧分布于阳坡和半阳坡.主成分分析结果显示,影响香榧生境的生态因子依次为水分、热量和土壤养分.香榧独特的生物生态学特性表明,水分可能是影响香榧生境形成的最重要的生态因子之一.  相似文献   

18.
Oniscvs ancarenisis from the Sierra de Ancares in northern Spain is described as new. The genus Oniscus now contains four species: ancarensis sp. nov. , asellus Linnaeus, lusitanus Verhoeff and simoni Budde-Lund. The distribution of these species is figured and discussed, and a key is given for their determination.  相似文献   

19.
A psychrotrophic Flexibacter sp., Flexibacter ovolyticus sp. nov., was isolated from the adherent bacterial epiflora of Atlantic halibut (Hippoglossus hippoglossus L.) eggs and was shown to be an opportunistic pathogen for halibut eggs and larvae. The strains which we isolated had the enzymatic capacity to dissolve both the chorion and the zona radiata of the egg shells. A total of 35 isolates were characterized by using morphological and biochemical tests. These strains were rod shaped, gram negative, Kovacs oxidase positive, and pale yellow and exhibited gliding motility. They did not produce acid from any of the wide range of carbohydrates tested. Our isolates had the ability to degrade gelatin, tyrosine, DNA, and Tween 80. Starch, cellulose, and chitin were not degraded. The strains were catalase and nitrate reductase positive, did not produce H2S, and did not grow under anaerobic conditions. F. ovolyticus resembles Flexibacter maritimus, but differs from the latter species in several biochemical and physiological characteristics. DNAs from F. ovolyticus strains had guanine-plus-cytosine contents which ranged from 30.3 to 32.0 mol% (strains EKC001, EKD002T [T = type strain], and VKB004), and DNA-DNA hybridization studies revealed levels of relatedness between F. ovolyticus EKD002T and F. maritimus NCMB 2154T and NCMB 2153 of 42.7 and 30.0%, respectively. Compared with previously described Cytophaga and Flexibacter spp. with low guanine-plus-cytosine contents, F. ovolyticus constitutes a new species. Strain EKD002 (= NCIMB 13127) is the type strain of the new species.  相似文献   

20.
Chloroplast DNA phylogeography of Alnus glutinosa (L.) Gaertn.   总被引:8,自引:0,他引:8  
Traditionally, information on the postglacial history of plant species has been gained from the analysis of fossil pollen data. More recently, surveys of present patterns of genetic variation have given valuable insights into species phylogeography. The genus Alnus , based on fossil data, is known to have had at least four glacial refugia. A survey of chloroplast DNA (cpDNA) diversity in populations of black alder ( A. glutinosa ) was undertaken in order to gain more insight into its postglacial history. This revealed a high degree of structuring of 13 cpDNA haplotypes on a European scale which indicated that most of northern and central Europe was colonized from a refuge in the Carpathian Mountains. Based on the distribution of two common cpDNA haplotypes, colonization routes from this refuge can be determined. The locations of other previously identified refugia are confirmed and two formerly unconfirmed refugial areas for alder (southern Spain and Turkey) are proposed.  相似文献   

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