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1.
A rare species of the spariform fish Acanthopagrus schlegelii from Russian waters is described. The synonymy of this species and the related literature data are analyzed. It is suggested that two species occur in Russian waters that differ in body coloration: A. schlegelii and A. czerskii.  相似文献   

2.
Systematics of adult lampreys based on the “paired species” concept divides anadromous and residential specimens mostly on the size and size-depended criteria. Larvae of the paired species are poorly distinguished, so scientists keep looking for new diagnostic features. In the present paper structure and coloration of the tongue precursor in Arctic lamprey, Lethenteron camtschaticum, from the watersheds of the Russian Far East, including the species type locality are discussed. The data show that use of Tongue Precursor Pigmentation as a key for species identification is premature because tongue precursor within species inhabiting one river system or the same region demonstrates all types of coloration. Structure of tongue precursor changes from triangular into bulbous during growth.  相似文献   

3.
The survival of insects that inhabit Canadian arctic regions depends on a number of factors which have important ecological, behavioral, physiological, and biochemical components. The ability to withstand low winter temperatures is one of the most conspicuous adaptations of northern insects and the one most closely studied in the laboratory. Most species studied so far conform to one or other of the two major overwintering strategies, namely, frost susceptibility, the ability to avoid freezing by supercooling to a considerable degree, or frost tolerance, the survival of actual ice formation within the body. The Arctic beetle, Pytho americanus Kirby, is frost tolerant in both larval and adult stages, a situation which would be congruous with its northern distribution and allow it to spread its life cycle over a number of growing seasons. The main biochemical correlates during the cold-hardening process in this species are increasing glycerol and decreasing glycogen concentrations. In addition to its normally assumed roles in cryoprotection there is evidence to suggest that glycerol may further serve to minimize dehydration in the overwintering insect by increasing the level of bound water. P. americanus larvae and adults have narrow supercooling ranges and maintain their supercooling points in the region of ?4 to ?8 °C. It is hypothesized that these elevated supercooling points are a result of the presence in the hemolymph of nucleating agents which ensure ice formation at high subzero temperatures.Low temperature tolerance strategies of some other arctic and alpine species have been examined and compared with those of relatives from more southerly latitudes. P. americanus has been collected in the Canadian Rockies at elevations of over 6000′, and its frost-tolerant attributes are identical to those of the population collected in the Arctic. A closely related species, P. deplanatus, from the Rockies, however, although it too exhibits frost tolerance in the larval stage, differs markedly from P. americanus in its ability to depress its supercooling range to ?54 °C. It appears that P. deplanatus does not have the ability to synthesize ice-nucleating agents and, therefore, can overwinter in a supercooled condition. Two congeneric species of willow leaf gall sawflies (Pontania spp.), one from Tuktoyaktuk, N.W.T., and the other from southern Vancouver Island have also been compared and contrasted. Pontania sp. on Salix glauca (Tuk., ca. 70 °N) is frost tolerant in its larval stage, has relatively high supercooling points (ca. ?9.0 °C), but does not accumulate glycerol. Pontania sp. from Salix lasiandra (Victoria, ca. 48 °N) has almost identical overwintering properties, indicating the close phylogenetic affinities of cold tolerance in this genus rather than independent adaptation to widely different climatic conditions. Some of the lowest supercooling points ever recorded are from willow stem gall forming insects. Rhabdophaga sp. (Cecidomyiidae) forms potato galls on the stems of Salix lanata in the Inuvik area, N.W.T. After low temperature acclimation, supercooling points down to ?66 °C have been recorded from individual larvae. This is a record, and it indicates that we may be dealing with a system in which most water is in a metabolically bound state. Glycerol levels reach 20% of the fresh body weight during this period. Diastrophus kincaidii Cynipidae) forms stem galls on Thimble Berry (Rubus parviflorus) on southern Vancouver Island. Both of the forementioned species overwinter as larvae in their galls and are, therefore, exposed to ambient air temperatures. A more benign winter climate on Vancouver Island is reflected in the fact that D. kincaidii has supercooling points only in the ?30 to ?33 °C range at the peak of low temperature acclimation, and glycerol levels just below 4% of fresh body weight. Both species are frost susceptible and depend on their supercooling abilities to survive low winter temperatures.  相似文献   

4.
We studied survival, mortality factors, and community structure of nine species of leaf-galling sawflies, Eupontania spp., living on ten willow species (Salix spp.) at six sites on the Russian arctic tundra. The sawfly species represented two different gall types: the viminalis-type, which forms pea-shaped galls on the underside of leaf blades, and the vesicator-type, which forms bean-shaped galls on both sides of the leaf blade. Gall communities in the northernmost site had only one parasitoid species, but up to six parasitoids were found at the southernmost site. Inquiline parasitoids were encountered only in the two southern sites. Survival of the larvae varied between 20.0 and 82.8% among galler species at different sites. Parasitoids were the most important mortality factor for the sawflies. They caused mortality of 7.8-65.4%, depending on galler species and site, and it was highest in the northernmost site. Plant-specific mortality varied from 1.7 to 28.4% by galler species and it tended to decrease towards the north. Mortality from parasitoids was greater in the vesicator-type gallers than in the viminalis-type gallers. The total mortality caused by parasitoids in the arctic communities does not appear to differ from that in the diverse southern communities of Eupontania in Middle Europe, Scandinavia and North America, despite the assemblage having only a few members in the Arctic. The largest difference between the southern and the northern communities was the lack of inquiline parasitoids in the north. Our data do not support the hypothesis that abiotic, rather than biotic, factors would be more important in determining the abundance of populations of herbivorous insects in the harsh arctic environment.  相似文献   

5.
A review of the species of the genus Osmoderma of Siberia and the Russian Far East is given. The species Osmoderma opicum coreanum Tauzin, 2013 was first identified in the fauna of Russia. The locality of O. davidis Fairmaire, 1887 in Buryatia, which was confirmed by material, is presented. The distribution of the East Asian species of this genus in the territory of Russia is analyzed in detail. The data on the phenology, trophic associations, and topical preferences are considered.  相似文献   

6.
The taxonomy of treeshrews (Order Scandentia) has long been complicated by ambiguous morphological species boundaries, and the treeshrews of the Palawan faunal region of the Philippines are no exception. Four named forms in the genus Tupaia Raffles, 1821, have been described from four island groups based on subtle qualitative morphological characters, and as many as three distinct species have been recognized. A recent molecular phylogenetic study of relationships among Tupaia species suggests that the two currently-recognized treeshrew species from the Palawan faunal region diverged very recently relative to other sister-species divergences within the genus and may not represent species-level taxonomic entities. Here we review the taxonomic and biogeographic histories of the Tupaia taxa from this region. We also collected craniodental data from 133 skulls of all four named forms, representing five island populations, and conducted univariate and multivariate analyses on these data. Our morphometric results are consistent with molecular results, further suggesting that there is insufficient evidence to recognize T. moellendorffi Matschie, 1898, as a separate species from T. palawanensis Thomas, 1894. Our analyses also revealed a craniodentally divergent population from the island of Balabac, which has never been considered a distinct subspecies (or species) from the population on Palawan. These results have conservation implications for the island populations in our analyses, but additional surveys and molecular evidence will be required to fully assess conservation priorities for the treeshrews of the Palawan faunal region.  相似文献   

7.
RFLP analysis of the ND4-ND5 genes of the mtDNA genome in Daphnia middendorffiana and three closely allied species was used to investigate its origin and age. Populations of D. middendorffiana from arctic Canada were found to possess three distinct mtDNA lineages, only one of which appears unique to this species. The other two mtDNA lineages are either closely allied or identical to haplotypes in D. pulicaria, suggesting that it is the maternal parent of many clones of D. middendorffiana. Within D. pulicaria, mtDNA lineages have largely disjunct distributions, suggesting that populations of this species persisted in three glacial refugia (arctic, western, eastern) during the Pleistocene. Hybridizations between these refugial stocks and other species such as D. melanica and D. pulex likely generated many of the polyploid lineages of D. middendorffiana following the Wisconsinan glaciation. The presence of one unique mtDNA lineage in D. middendorffiana suggests that at least some of its clones are more ancient, but further studies are needed to rule out the possibility of their recent derivation from an as yet undetected sexual species. As a general result, this study suggests that polyploid cladocerans are unlikely to predate the Pleistocene.  相似文献   

8.
Rhaponticum carthamoides (Willd.) Iljin is a perennial herb, commonly known as a maral root or Russian leuzea, which has been used for centuries in eastern parts of Russia for its marked medicinal properties. This review based on 117 literary sources, with many of them being originally published in non-English languages (mainly in Russian), discusses the current knowledge of traditional uses, chemistry, biological effects and toxicity of this species. Several different classes of compounds were previously isolated from various parts of R. carthamoides of which the main groups are steroids, particularly ecdysteroids, and phenolics (flavonoids and phenolic acids) accompanied with polyacetylenes, sesquiterpene lactones, triterpenoid glycosides and terpenes (essential oil). A comprehensive account of the chemical constituents is given in this review (figures of 120 structures are shown). Various types of preparations, extracts and individual compounds derived from this species have been found to possess a broad spectrum of pharmacological effects on several organs such as the brain, blood, cardiovascular and nervous systems as well as on different biochemical processes and physiological functions including proteosynthesis, work capacity, reproduction, and sexual function. Moreover, the extracts and preparations from the plant, which are hopefully safe, exhibited various additional biological effects e.g. antioxidant, immunomodulatory, anticancerogenic, antimicrobial, antiparasitic and insect antifeedant or repellent activities. The results of data analysis on the chemical, pharmacological and toxicological characteristics of R. carthamoides support the view that this species has beneficial therapeutic properties and indicate its potential as an effective adaptogenic herbal remedy. Finally, some suggestions for further research on chemical and pharmacological properties are given in this review.  相似文献   

9.
Differences in carbon and nutrient fractions among arctic growth forms   总被引:3,自引:0,他引:3  
Summary In a survey of 28 plant species of 6 major growth forms from Alaskan tundra, we found no consistent difference among growth forms in the chemical nature of stored reserves except for lichens and mosses (which stored C primarily as polysaccharides) and shrubs (which tended to store C more as sugars than as polysaccharides). Forbs and graminoids showed particularly great diversity in the chemical nature of stored reserves. In contrast, C, N, and P chemistry of leaves was strikingly similar among all species and growth forms. Concentrations of stored reserves of C, N, and P were highest and showed greatest seasonal fluctuations in forbs and graminoids but were relatively constant in evergreen shrubs. From this information, we draw three general conclusions: (1) the photosynthetic function of leaves strongly constrains leaf chemistry so that similar chemical composition is found in all species and growth forms: (2) the chemical nature of storage reserves is highly variable, both within and among growth forms; (3) the concentration and seasonal pattern of storage reserves are closely linked to growth-form and reflect growth-form differences in woodiness, phenology, and relative dependence upon concurrent uptake vs. storage in support of growth.  相似文献   

10.
《Palaeoworld》2020,29(1):176-181
For the first time in the south of the Russian Far East in the Late Pleistocene cave deposits, fragments of the giant flying squirrel of the genus Petaurista were discovered. Petaurista tetyukhensis n. sp. is described based on a fragment of the upper jaw with two teeth and five isolated teeth from two cave locations. The main differences between the new species and living forms as well as other fossil species of the genus Petaurista are the absence of vertical groove on the lingual wall between the protocone and hypocone on M2, the absence of the anterior cross loph on the upper P4-M3, and the absence of mesoconids on lower, as a result of which the hypoflexid is not w-shaped. It is suggested that the Sikhote-Alin refugium allowed individual species to survive there during long unfavourable period of time and was the centre of speciation.  相似文献   

11.
New data are presented on the occurrence in the Russian waters of the Barents Sea of 30 species of rare fishes. These data significantly change knowledge on their geographic distribution. For the first time, the presence in the Russian zone of seven species is indicated: Raja lintea (Rajidae), Chimaera monstrosa (Chimaeridae), Gadiculus argenteus thori and Micromesistius poutassou (Gadidae), Gaidropsarus argentatus (Lotidae), Sebastes viviparus (Sebastidae), and Lycodus luetkeni (Zoarcidae).  相似文献   

12.
The arctic skua (Stercorarius parasiticus) is one of the most long‐lived bird species. In 2010, we captured in Finland an adult, female arctic skua which had been ringed as a nestling in 1987. We tagged it also with a color ring. The bird has last been seen in July 2020 at the age of 33 years, making it most likely the oldest known arctic skua of the world. In 2010–2011 the bird carried a light‐level measuring geolocator, the data of which revealed that the bird had spent the nonbreeding season in the Canary Current area on the west coast of Africa. Breeding populations of arctic skuas have declined recently especially in British Isles, thus it is useful to get longevity data of this species with a high breeding site fidelity.  相似文献   

13.
A taxonomic review of seven species of Diplocheila of the Far East of Russia and adjacent lands is given. Three species are known from the Russian Far East, two of which, D. zeelandica Redt. and D. minima Jedl., are recorded from Russia for the first time. A key to the East Asian species is presented. Composition and diagnoses of subgenera are discussed. The subgenus Submera Habu is restored.  相似文献   

14.
15.
A review that considers in detail for the first time the taxonomic position, phenetic diversity, and principal features of the endemic species East Siberian char Salvelinus leucomaenis in the range from the northeast of Asia to Japan based on own and published data is provided. In comparison with other species of chars, S. leucomaenis is characterized by a smaller morphological and ecological diversity. A migratory form feeding on fish is dominant in the range. At the same time, parallel to large migratory forms, other life forms—resident riverine and lacustrine-riverine forms represented by males and females and riverine and dwarf males were found in S. leucomaenis. Individuals with various color variations occur everywhere. Resident forms are rare in the north of the range; they are dominant in the south of the range, in Japan.  相似文献   

16.
An overview of the literature changes in the systematics of algae in the order Laminariales (Phaeophyta) based on molecular phylogentic data is given. In a recent taxonomic revision by Lane et al., [45], the number and status of the families traditionally included in the order have been revised. One family was transferred to the order Tilopteridales; a new family, the Costariaceae, was described; and the genus Laminaria was split into 2 genera, Laminaria and a newly resurrected genus Saccharina. These innovations have necessitated a systematic revision of the Far Eastern species of the Laminariales. Our genetic studies indicate that 2 species of Laminaria and 12 intraspecific taxa (1 subspecies and 11 forms) from the Russian Pacific coasts should be transferred to the genus Saccharina. The following new nomenclatural combinations are proposed: Saccharina bongardiana, comb. nov. (including 4 forms: f. bifurcata, f. subsessilis, f. subsimplex, f. taeniata) and Saccharina gurjanovae, comb. nov. (including f. lanciformis). In addition, new nomenclature combinations are proposed for intraspecific taxa of the Laminaria species (L. angustata, L. cichorioides, L. japonica) that have already been transferred to the genus Saccharina [45]. These include S. angustata subsp. sibirica, comb. nov., 4 new combinations for the forms of S. cichorioides (f. coriacea, f. sacchalinensis, f. sikotanensis, and f. sinuicola), and 2 new combinations for the forms of S. japonica (f. diabolica, and f. longipes). The taxonomic status of the rest of the members of the Laminariales known from the seas of the Russian Far East is discussed. Laminariaceous algae in this area represent 6 of the 8 known families currently included in the Laminariales (Chordaceae, Pseudochordaceae, Alariaceae, Arthrothamnaceae, Laminariaceae, and Costariaceae).  相似文献   

17.
《Flora》2005,200(4):321-325
During the last decades, it has been shown that arctic plants show larger variation in reproductive strategies than traditionally assumed. Obligate outcrossing based on a self-incompatibility system is, however, very rare in the typically harsh, insect-poor arctic environment. Here we present the second, to our knowledge, documented example of a fully self-incompatible arctic species, Draba palanderiana Kjellm. Because of its large, scented flowers and frequently aborted fruits it has been suggested that this species is strictly outcrossing. To test this hypothesis, we conducted a pollination experiment with two populations from arctic North America. Pollen stainabilities were above 80% in most plants. Full female and male fertility was demonstrated by crosses resulting in fertile F1 offspring. In contrast, no viable seeds were obtained after spontaneous or hand-facilitated selfing, demonstrating that these D. palanderiana populations are fully self-incompatible and thus obligately outcrossing.  相似文献   

18.
The Don Basin rivers confined to Saratov oblast were searched for the Russian desman in 2009–2011. The suitability of habitats for this species was assessed. Potentially negative factors for the Russian desman (Desmana moschata) in various types of habitats were detected, and their intensities were assessed. The small tributaries of the Khopyor and Medveditsa rivers have turned out to be suitable for the Russian desman; however, neither animals nor any sign of their life activities have been found using different techniques. Nonetheless, we cannot state that this species is absent in the small rivers of the Saratov oblast; however, if this species is present in the examined area, its abundance is extremely low. A drastic decrease in the Russian desman population and even its disappearance are most likely associated with intraspecific processes, factors of a global scale, and immigration of new species previously not found in the river ecosystems in the examined areas.  相似文献   

19.
It is now well established that European earthworms are re-shaping formerly glaciated forests in North America with dramatic ecological consequences. However, few have considered the potential invasiveness of this species assemblage in the European arctic. Here we argue that some earthworm species (Lumbricus rubellus, Lumbricus terrestris and Aporrectodea sp.) with great geomorphological impact (geoengineering species) are non-native and invasive in the Fennoscandian arctic birch forests, where they have been introduced by agrarian settlers and most recently through recreational fishing and gardening. Our exploratory surveys indicate no obvious historical dispersal mechanism that can explain early arrival of these earthworms into the Fennoscandian arctic: that is, these species do not appear to establish naturally along coastlines mimicking conditions following deglaciation in Fennoscandia, nor were they spread by early native (Sami) cultures. The importance of anthropogenic sources and the invasive characteristics of L. rubellus and Aporrectodea sp. in the arctic is evident from their radiation outwards from abandoned farms and modern cabin lawns into adjacent arctic birch forests. They appear to outcompete previously established litter-dwelling earthworm species (i.e. Dendrobaena octaedra) that likely colonized the Fennoscandian landscape rapidly following deglaciation via hydrochory and/or dispersal by early Sami settlements. The high geoengineering earthworm biomasses, their recognized ecological impact in other formerly glaciated environments, and their persistence once established leads us to suggest that geoengineering earthworms may pose a potent threat to some of the most remote and protected arctic environments in northern Europe.  相似文献   

20.
Grouping organisms into categories based on common traits has been a tool of ecological scientists for some time now. Defining groups of species, examples being life forms and functional types, is an operational procedure, conducted to answer a particular question. This becomes rather practical when performing analyses at coarse spatial scales, given data limitations and the potential for species redundancy. However, the implications of aggregating organisms for modeling purposes are still unclear. Does averaging the traits of several species into a functional type sufficiently represent the dynamics of the individual components? How much variability is lost when we aggregate species into groups? In an attempt to address these questions, we examined how the level of vegetation aggregation affected a variety of ecosystem properties using a regional‐scale model of arctic tundra ecosystems (ArcVeg).
We used four levels of aggregation: species (15 dominant ones), functional types (7), life forms (4) and vegetation type (1), in addition to two methods of aggregation (simple vs weighted means of plant parameter values). We found that the level of aggregation consistently affected community composition, total community biomass and ecosystem net primary production (NPP). Neither simple means nor weighted means of aggregated parameter values adequately captured the ecosystem properties simulated at lower levels of aggregation. Aggregation of vegetation (i.e. reduced parameter variability) using simple means underestimated total biomass, whereas aggregation using weighted means overestimated total biomass. Aggregation led to increases in NPP with both methods. These findings suggest that aggregating vegetation, particularly to levels less detailed than plant functional types, will have important implications for regional‐scale modeling of vegetation dynamics and carbon cycling.  相似文献   

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