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1.
Zi-Wei Yin  Li-Zhen Li 《ZooKeys》2013,(346):23-27
Tangius indicus sp. n. (Batrisitae: Batrisini) is described and illustrated from the Indian States of Meghalaya (Khasi Hills, type locality) and West Bengal (Darjeeling). Specimens of the new species are similar to those of the recently described T. glabellus Yin & Li from Tibet, Southwest China, and can be separated only by minor differences of the male features.  相似文献   

2.
Twig beetles in the genus Pityophthorus Eichhoff, 1864 include more than 300 species worldwide, with maximum diversity in tropical and subtropical regions. To date, approximately 50 species of Pityophthorus have been recorded in Canada, and these species are associated mainly with coniferous trees. Since 1981, no comprehensive study on this difficult taxonomic group has been conducted in Quebec, Canada, most likely due to their limited significance as forest pests. Based on data gathered from five years of field sampling in conifer seed orchards and compiled from various entomological collections, the distribution of Pityophthorus species in Quebec is presented. Approximately 291 new localities were recorded for the Pityophthorus species. Five species-group taxa, namely Pityophthorus puberulus (LeConte, 1868), Pityophthorus pulchellus pulchellus Eichhoff, 1869, Pityophthorus pulicarius (Zimmermann, 1868), Pityophthorus nitidus Swaine, 1917,and Pityophthorus cariniceps LeConte&Horn, 1876 were the most widespread. In contrast, Pityophthorus consimilis LeConte, 1878, Pityophthorus intextus Swaine, 1917, Pityophthorus dentifrons Blackman, 1922, Pityophthorus ramiperda Swaine, 1917, and Pityophthorus concavus Blackman, 1928 display a notably limited distribution. In addition, the first distribution records of Pityophthorus intextus and Pityophthorus biovalis Blackman, 1922 are furnished, and the subspecies Pityophthorus murrayanae murrayanae Blackman, 1922is reported from Quebec for the second time. Moreover, distribution maps are provided for all Pityophthorus species recorded in the province of Quebec.  相似文献   

3.
Rapid growth of ground vegetation following clear-cutting is important to site productivity because vegetation retains nutrients in the ecosystem and can decrease nutrient leaching prior to stand re-establishment. Aboveground biomass, nutrient contents (N, P, K and Ca) and species composition of ground vegetation were determined 1 year before and for 7 years after clear-cutting of a mixed forest dominated by Norway spruce [Picea abies (L.) H. Karst.] in eastern Finland. The biomass of the feather mosses [Pleurozium schreberi Brid. and Hylocomium splendens (Hedw.) B. S.& G.] and the dwarf shrubs (Vaccinium myrtillus L. and V. vitis-idaea L.), which had dominated the ground vegetation in the mature forest, significantly decreased after clear-cutting. However, with the exception of H. splendens, these species had recovered within 3–5 years. The biomass of Deschampsia flexuosa (L.) Trin. considerably increased soon after clear-cutting, and Epilobium angustifolium L. appeared 3–5 years after cutting. These species contributed to the retention of nutrients not simply because of their biomass but also because of higher nutrient concentrations in their tissues. Total biomass and nutrient contents of the ground vegetation exceeded those of the pre-cutting levels. The proportion of ground vegetation biomass and nutrient contents represented by mosses decreased after cutting, while V. myrtillus, although reduced after cutting, remained a marked nutrient sink. The results suggest that H. splendens is the most sensitive species to cutting, but the biomass of P. schreberi, V. myrtillus and V. vitis-idaea return to initial levels soon after clear-cutting as do the nutrient contents of ground vegetation.  相似文献   

4.
Daily stem radial growth of balsam fir [ Abies balsamea (L.) Mill.] was studied between 1998 and 2001 using automated point dendrometers to investigate meteorological influence. By dividing the dendrometer day-night variation, the diurnal growth pattern was resolved into the three phases of (1) contraction, (2) expansion and (3) stem radius increment (SRI). The entire circadian cycle (4) defined by the three previous phases was considered as a fourth phase. The mean weather conditions of each phase were compared with the SRI using simple correlation and response function analysis. It was found that the weather conditions prevailing from 1600/1700 hours to 0800/0900 hours corresponding with the expansion-SRI phases had greater impact on SRI. Response function results confirmed most of the correlation analyses and explained up to 95% of the variance of the SRI series. Total rainfall in phases 2, 3 and 4 was correlated positively with SRI, and hence verifies the importance of daily water balance. The importance of water was also demonstrated by the negative effect of high vapour pressure deficit of phase 2, decreasing the possibility of cell radial expansion. The maximum temperature of phase 3 was the only temperature variable having a positive impact on SRI suggesting that night temperature was more important than day temperature in controlling radial growth. These results may influence the process of cell enlargement and reflect only the mechanical aspect of growth.  相似文献   

5.
Pollen records suggest that Abies alba played a dominating role in both the montane and lowland forests at the border of the Southern Alps between ca. 8500 and 5700 years ago. Two major declines in fir, at about 7300–7000 cal b.p. and at ca. 6000 cal b.p., followed by the local extinction of the species are characteristic of the area below ca. 1000 m a.s.l. In order to test the impact of fire on the population dynamics of silver fir, a dynamic model (DisCForm) with a fire module was applied to simulate the early- and mid-Holocene forest development. Simulation outputs based on different fire scenarios were compared with the pollen record from Lago di Annone (226 m a.s.l.). The marked Abies decreases shown in the pollen record can be simulated with very intensive fire scenarios, but they do not result in an extinction of silver fir in the model. Low charcoal influx values related to the Abies declines in the palaeobotanical record suggest that fire was not the only reason for the extinction of silver fir. Human impact, as well as Holocene climatic changes leading to temporary moisture deficits and reduced adaptability due to low genetic variation may have had a significant impact on the Abies forests.  相似文献   

6.
New records of four species (Lema lacertosa Lacordaire, 1845, Lema diversipes Pic, 1921, Lema cyanella (Linnaeus, 1758), Lema trivittata trivittata Say, 1824 and additional information on one recently recorded species (Lema solani Fabricius, 1798) are reported for Taiwan. Lema diversipes Pic, 1921 is removed from synonymy with Lema lacertosa Lacordaire, 1845; both species are redescribed. A lectotype is designated for Lema phungi Pic, 1924. The synonymies of Lema phungi Pic, 1924 and Lema jeanvoinei Pic, 1932 with Lema lacertosa Lacordaire, 1845 are supported. A revised key to the known species in Taiwan is provided.  相似文献   

7.
Fariba Mozaffarian 《ZooKeys》2013,(319):231-248
Iran is known as the most complex and varied country in southwest Asia, in terms of geography, vegetation, climate and consequently biological diversity. The rather high number of recorded endemic species of Fulgoromorpha in Iran indicates a high potential for speciation in some areas.In this study, in order to identify the endemic zones for Fulgoromorpha of Iran, three main biogeographic regions of the country were divided into 13 primary zones, mainly according to the distribution of published and unpublished locality records of endemic species. Using Venn diagrams and cluster analyses on the primary zones, 6 final endemic zones were recognized: Caspian zone, southern slopes of Alborz, Zagros Mountains, Kerman Mountains, Khorasan Mountains, and Baluchestan and Persian Gulf coasts. Then a similarity map was produced for endemic zones using a Multidimensional analysis (Alscal) and the differences between the positions of the same zones in the similarity and geographic maps were discussed.  相似文献   

8.
Yin ZW  Li LZ  Zhao MJ 《ZooKeys》2012,(175):75-86
Two new species, Pselaphodes linae Yin & Li, sp. n. (Hainan, Fujian) and Pselaphodes shii Yin & Li, sp. n. (Hainan) are described from South China. Taiwanophodes minor Hlaváč is reported from outside Taiwan for the first time. Illustrations of major diagnostic features are provided for all treated taxa. The latest key to Chinese Pselaphodes is modified to include the new species.  相似文献   

9.
Summary Malpighian tubules of a desert tenebrionid beetle,Onymacris plana, have been studied as isolated preparations. Under control conditions tubules of female beetles secreted fluid at an average rate of 3.3 nl/min, but this rate was increased 20–25 times by a diuretic hormone (DH).Homogenates of the brain, corpora cardiaca (CC) and prothoracic ganglion induced striking increases in tubule secretion rates, which sometimes exceeded 100 nl/min. The increased rates were sustained for 3 h without renewal of the medium. Diuretic activity was also present in the other thoracic ganglia. High K treatment caused release of DH from the CC only.Exogenous cyclic AMP (1 mM) stimulated the isolated tubules ofO. plana, but to a lesser extent than the DH. The cationic composition of the secreted fluid resembled that of most other insect tubules, with high K and low Na concentrations. Stimulation with DH doubled the Na concentration.The DH was not inactivated by the tubules themselves, but was destroyed by contact with the haemolymph. An inactivation mechanism is vital in the apparently contradictory situation of a desert beetle possessing a diuretic hormone. The role of the cryptonephric system during diuresis is unknown.Abbreviations DH diuretic hormone - cAMP adenosine 3:5-cyclic monophosphoric acid - CC corpora cardiaca  相似文献   

10.
The distribution of alectorioid lichens in subalpine spruce–fir forests of north-central British Columbia is strongly influenced by vertical position within the canopy; Bryoria dominates upper canopy exposures, while Alectoria dominates lower canopy positions. The hypothesis that this height-related niche partitioning reflects differential growth responses to gradients in canopy microclimate is examined. Field measurements of canopy microclimate, taken over a 2-year period, were used in conjunction with laboratory-based measurements of net photosynthesis (NP) and dark respiration to model net assimilation (NA) response of Alectoria sarmentosa and Bryoria spp. (mixed collections of Bryoria fremontii and B. pseudofuscescens) at two different heights (15 and 4 m) within the canopy. Microclimate measurements indicate that lichen thalli are regularly hydrated from snowmelt events during the winter period (October–April), totalling 26 and 29% of the time, respectively, for Alectoria and Bryoria, though most winter hydration exposure (c. 75%) occurred in the dark. In the summer (May–September), rainfall was the major hydration source, with Alectoria and Bryoria each hydrated c. 16% of the time (45% of this in the dark). The NP temperature optimum (Topt) in light saturated thalli of Alectoria was 18·1 and 22·9°C, for winter and summer measurements, respectively. In Bryoria the corresponding seasonal rise in Toptwas smaller, from 15·9 to 16·3°C. Both species showed an increase in maximum rates of NP during the summer period, from 1·52 to 1·92 mg CO2 g−1 h−1for Alectoria, and from 1·79 to 2·33 mg CO2 g−1 h−1for Bryoria. Although lichen hydration events peaked in early winter (October and November), NA modelling predicts that maximum growth should occur during the summer period. In Alectoria, higher rates of NA were predicted for thalli in lower canopy positions, especially during the summer months. In Bryoria, no clear trends of NA uptake with canopy position were observed. Thus, while NP response to gradients of canopy microclimate may provide a basis for niche partitioning in Alectoria, other factors (perhaps exclusionary) may be more important for Bryoria. One such factor is documented, namely the greater sensitivity of Bryoria to extended hydration exposure and we speculate that greater rates of fragmentation in upper canopy exposures may limit upper canopy biomass accumulation in Alectoria. Niche partitioning in these alectorioid lichens may therefore reflect both positive (growth responses) and negative (physical and physiological limitations) responses to gradients in canopy microclimate.  相似文献   

11.
12.
Two new Neotropical species of Ceracis Mellié are described: Ceracis cassumbensis Antunes-Carvalho & Lopes-Andrade, sp. n. from a single locality in northeastern Brazil and Ceracis navarretei Antunes-Carvalho & Lopes-Andrade, sp. n. from a single locality in southern Mexico. Scanning Electron Microscope images of adults and photographs of holotypes and male terminalia are provided for both species, their similarities and differences with other Ceracis are briefly discussed, and the cucullatus species-group is redefined for including the new species described herein.  相似文献   

13.
Morphological and karyotypical features of a new blackfly species Cnetha akopi sp. n. from Armenia are described. Comparative analysis of the new species and four closely related endemic species from Caucasus is performed. Photographic maps of polythene chromosomes are provided.  相似文献   

14.
Fish species of the Zungaro genus (Siluriformes, Pimelodidae) are amongst the largest migratory fish in Latin America and have considerable economic importance for commercial fishing in Brazil. However, natural populations of this large catfish are experiencing a severe decline. There are significant taxonomical inconsistencies for this fish. Two geographically separated species of the fish were initially described, one endemic in the Amazon and another in the Paraná-Paraguay River basins. A taxonomic review had recently proposed that there is only one Zungaro species in Brazil, based on morphological data. We made a molecular study of Zungaro populations in an attempt to solve taxonomical inconsistencies and to analyze genetic diversity in natural populations of this genus. We analyzed two regions of the mitochondrial DNA (the control region and the ATPase 6 gene region) of individuals sampled from the Paraná-Paraguay River and Amazon River basins. Analyses based on p-distances and maximum likelihood phylogenetic models showed a genetic difference between populations corresponding to different species. Genetic differentiation between Zungaro populations was at the same level as that observed between other Siluriformes species, using the same DNA sequences. We conclude that Zungaro species of the Paraná-Paraguay River basin do not belong to the same species found in the Amazon basin. This finding has a significant implication for conservation of this fish, given that populations are disappearing at a high rate in the Paraná-Paraguay River basin, mainly due to impoundments.  相似文献   

15.
16.
In this study, the potential exposure of non-targeted adult rove beetles and their larvae to Bt toxins (Cry34Ab1, Cry35Ab1, Cry1F (59122 and 1507×59122) designed to target western corn rootworm and European corn borer has been determined. The overall assemblage was not significantly affected by the production of stacked proteins.  相似文献   

17.
The physical and chemical variabilities as well as the distribution of diatoms of six boreal lakes in the Laurentian Mountains (southern Québec, Canada) were studied. The lakes are located along an altitudinal gradient and were sampled at a biweekly resolution from May through October, 2002. In general, we found later onset and weaker lake stratification under colder climates. Lake circulation and SiO2 are strongly correlated and together significantly explain the distribution of diatoms of the individual lakes. Diatoms that accumulated in the sediment traps were mostly composed of benthic species, suggesting resuspension. However, diatom flux and lake circulation were not significantly correlated, the diatom assemblages in the sediment traps were similar in two consecutive years, and species–environment relationships were comparable among lakes, which indicates that the effects of resuspension were minimal. In addition, we found that one lake was more productive due to forest logging. The forest in the catchment of Lake Maxi was entirely clear-cut shortly prior to our sampling. Mean total phosphorus, dissolved organic carbon, and chlorophyll a concentrations were significantly higher when compared to the other five study lakes. This study seeks to improve our understanding of how diatoms in boreal lakes respond to climate change and forest clear-cut.  相似文献   

18.
In times of mass occurrence, massive numbers of the outbreaking species serve as food sources not only to predators and parasitoids but also to scavengers and decomposers. One example benefiting from this process is the necrophagous guild, which depends on a carcass for nutrition and reproduction. A well-known outbreaking insect is the forest cockchafer Melolontha hippocastani F. It inhabits woodlands on sandy soils, the same habitat as Nicrophorus vespilloides Herbst—a common burying beetle feeding on a variety of animal carcass. In this regard, N. vespilloides may come in contact with plant protective agents applied to control M. hippocastani populations. In a laboratory trial, we studied sublethal effects of NeemAzal®-T/S on the reproductive output of female N. vespilloides. They were previously fed with cockchafers, which in turn had been fed with neem-treated leaves. It was shown that female beetles fed with ‘treated’ cockchafers were negatively affected in carcass burying behavior and egg-laying. Furthermore, reduction in larval hatching and survival during the parental feeding phase caused further diminution of the reproductive output. On the other hand, neither impacts on mean larval weights nor morphological malformations in N. vespilloides were observed. Transferability of the results into the field is discussed.  相似文献   

19.
Gonad maturation in wild Cybister brevis Aubé, 1838 from Japan was investigated to determine the physiological mating season. Breeding experiments showed that hatching occurred from May to September, and the peak was observed in July. The gonadosomatic index (GSI) in collected females (ovary development) showed the highest value in May. The GSIs were low in other seasons. On the other hand, the GSIs in collected males (testes and accessory glands) remained at constant values during the experimental period. Interestingly, high sperm motility was exhibited in May and September, whereas it was low in December and March. This indicates the maturation difference between females and males. Females mature only at the beginning of the breeding season (May), but males do so from May to September. This result suggests that males have a wide-ranging maturation period and earlier sexual maturation than females, ensuring a successful fertilization.  相似文献   

20.
Kwiatkowski A 《ZooKeys》2011,(100):447-459
During a period of three years (2006-2008) the carabid fauna in wet and humid forest habitats of different stages of succession was studied at the Puszcza Knyszynska (north-east part of Poland). The aim of this study was to determine how the assemblages of the carabid fauna change in relation to the ongoing process of succession. Using pitfall traps, 24 plots were sampled. The plots were located in stands of different age, from two year old plantations to more than 100 year old forests. Additionally, the stands were ordered in three moisture classes (wet, humid and very humid) and two classes of soil richness. As indicators for change in the carabid fauna in relation to age of the stands Mean Individual Biomass (MIB), species diversity and share of forest species were used. By applying multivariate statistics the relation of the different habitat characteristics to changes in the carabid fauna was examined. During the study 8903 individuals belonging to 57 species were collected. Pterostichus niger represented 28% of the total catches and therefore the most common species. Another common species, Pterostichus melanarius, contributed to 13% of the total catch. This species was caught at every plot, even in the old forests. In contrast to the results obtained by Szyszko (1990) for fresh and dry pine stands, in this study the relation of MIB with the age of forest was not significant. Although the number of species was rather constant, the number of individuals belonging to the group of forest species significantly increased with the ageing of the forest. The multivariate analysis showed a relationship with ageing of the stands and soil richness rather than with moisture and size of the forest. According to the present paper, clear cuttings in wet and humid habitats do not cause a strong degradation of the carabid fauna.  相似文献   

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