Intraspecies variability of chaetotactic characteristics of the red mites of Hirsutiella genus (Acari: Trombiculidae)

Numbers of scutal, coxal and sternal setae were counted in 1393 specimens of 5 Hirsutiella species. All observed chaetotactic anomalies were classified into 3 groups: 1) "rare" anomalies, such as absence of one AL, AM, coxal or sternal setae, presence of additional AL, AM, coxal or anterior sternal setae; 2) presence of 1-2 post-posterolateral soutal setae (PPL); 3) presence of additional 1-3 posterior sternal setae. "Rare" anomalies were found in 2.8% of the specimens examined. They were observed usually in northern or alpine populations. Obviously, it is an effect of more frequent ontogenetic failures in rigorous climate conditions being out of optimum for trombiculids. The quota of the individuals with PPL in a set of H. steineri samples varied from 16 to 74%, while in the other samples of this species the presence of the single (and not more) PPL were found very seldom, as well as in the other species examined. In the similar way, the additional posterior sternal setae were found with the frequency up to 100% in the some samples of H. steineri, H. hexasternalis and H. alpina, but in other ones they were present only in few specimens. Since in a series of cases the ratio of the number of specimens with PPL to the number of specimens without PPL, as well as the ratio of the number of specimens with fSt = 2.4 to the number of specimens with fSt = 2.2 is almost equal to 2, one can suppose that the variance of this characters has a genetic basis. All samples having a high frequency of the PPL appearance or the appearance of additional posterior sternal setae were collected in the alpine zone. It is an evident example of the ecogeographical rules, which were reported previously by the author for the quantitative characters in species of the genera Neotrombicula (Stekolnikov, 1996, 1998, 1999) and Hirsutiella (Stekolnikov, 2001). It is possible that the PPL appearance is caused by the higher humidity of the climate, and the appearance of additional posterior sternal setae--by the low temperature. It is supported by the fact that the samples with high friquency of individuals having PPL are specific to damp areas of Western Caucasus, while the populations with high frequency of additional posterior sternal setae appear to be characteristic for regions with more dry climate (Daghestan, Turkey, Chelyabinsk Region of Russia). The fact, that in some populations of H. steineri, the individuals having PPL are prevalent, can serve as a serious argument for the abolishment of the genera Hoffmannina Brennan et Jones, 1959 and Aboriginesia Kudryashova, 1993 distinguished from related groups only by the presence of this setae.     

Changes in Vegetation and Earthworm Populations under Free Grazing European Bison (<Emphasis Type="Italic">Bison bonasus</Emphasis>) in Broad-Leaved Forests of the Kaluzhskie Zaseki State Nature Reserve

This paper studies the impact of a free-ranging bison population on the vegetation and soil fauna in spatially adjacent biotopes (meadow-transition zone-surrounding forest) in the Kaluzhskie Zaseki State Nature Reserve. It is noted that bison maintains meadows in the absence of haymaking. Analysis of phytosociological relevés shows that the forest vegetation has been significantly transformed by bison over 10–15 years, as evident from (1) differences in the ecological-coenotic structure of the vegetation in the different biotopes, (2) a larger ecological-coenotic diversity of communities in the transition zones in comparison with surrounding forests, and (3) an increase in the participation of nitrophilous species in the vegetation. A fairly high earthworm species diversity (a total of seven species in the biotopes) is found; Aporrectodea caliginosa dominates in the earthworm density and biomass. The total earthworm density and biomass became lower in the transition zone than in neighboring forests and meadows, and the differences in earthworm density between the transition zone and the meadows were statistically significant.     

Spatial distribution of <Emphasis Type="Italic">Marmota baibacina</Emphasis> and <Emphasis Type="Italic">M. sibirica</Emphasis> (<Emphasis Type="Italic">Marmota</Emphasis>, Sciuridae,Rodentia) in a zone of sympatry in Mongolian Altai: Bioacoustic analysis

The spatial distribution of two marmot species Marmota baibacina and M. sibirica in a zone of coexistence was studied by using their alarm call as a diagnostic trait. It was found that M. baibacina prefers to inhabit bouldery screes, whereas M. sibirica inhabits all suitable biotopes. The difference in biotopic distribution of these species could be explained by M. sibirica forcing M. baibacina out of optimum habitats. Cases of coexistence of both species in one family group sites were registered, which might contribute to the appearance of hybrids.     

Revision von Lathyrus L. sect. Lathyrostylis (Griseb.) Bässler (Fabaceae)

Lathyrus sect. Lathyrostylis includes 20 Eurasian species that are more or less xerophytic. They are mainly distributed in South Europe and Southwest Asia, especially in Turkey. The majority of the species inhabits dry meadows, scrubs, Pinus forests, macchies, rocky slopes and screes. The following diagnostic characters are valuable: All species are perennial. The pinnate leaves consist of (1–)2–3(–8) pairs of parallelveined, amphistomatic leaflets and the rachis ending in a simple tip. The style is linear to broadly spathulate but not twisted. Within the section neither subsections nor series can be distinguished. The study is mainly based on herbarium specimens. Only few species had been cultivated. A key to species and subspecies and new maps, mainly based on revised herbarium specimens, are given. Species and infraspecific taxa are described, and their variability, relationships, phytogeography and ecology are discussed. At last some supplements and corrections to the revision of Lathyrus sect. Orobus (Bässler 1973) are added.     

Assemblages of surface-dwelling Collembolans in Moscow Province. 1. Structure and dynamics of meadow and forest complexes

Data on the species composition, structure, and seasonal changes in the dynamic density of surfaceactive Collembola communities in meadows and forests of Moscow Province are provided. A total of 27 epigeic species were recorded from May to October in four biotopes (18–24 in each biotope) using pitfall traps. All of the communities studied consist of 1–2 dominant species, several subdominants, and 11–19 rare species, with the prevalence of Entomobryomorpha and Symphypleona. The springtail communities in the studied forest and meadow biotopes are very similar in species composition but differ in the relative abundance of individual species. The total dynamic density of epigeic species was shown to vary during the season, being significantly dependent on the type of biotope and the time of survey. The maximum density was recorded at the beginning of the active season (May–June); the minimum density was observed in August.     

云南迪庆州传统藏药雪莲资源的保护和可持续利用

对云南省迪庆藏族自治州传统藏药雪莲资源及其利用的状况进行了调查。通过调查发现该地区雪莲植物共有22种及1变种,市场上常当作商品出售的有5种。雪莲每年的贸易量达到55000kg,而且资源利用方式落后,已经造成雪莲特别是二年生的雪莲个体数明显减少,严重威胁了这些物种的生存。依据调查结果,建议提高人们的保护意识,控制雪莲的采集量、限制一年生雪莲采集的时间以及禁止多年生雪莲的采集。     

Soil alters seedling establishment responses to climate

Ecologists expect species and biomes to shift poleward and upward with climate change, but non‐climatic factors complicate these predictions. In mountains, forests are expected to expand upward along climate gradients into subalpine/alpine meadows, while meadows expand upward onto bare ground. However, soils also vary across elevation, with bare soil above the meadows potentially poorer for plant establishment. Poor soil might constrain expansion at meadows' upper edges, while rich meadow soil might facilitate contraction at lower edges by promoting tree establishment. We assessed climate and soil effects on establishment by transplanting soil and seedlings of meadow and tree species across climate gradients on Mount Rainier. There were considerable interspecific differences, but some generalisations emerged. Survival often declined with earlier snow disappearance, with somewhat smaller declines in meadow soil. Size often increased with earlier snow disappearance, with larger increases in meadow soil. Thus, soil patterns may complicate range shifts.     

Population limitation of the northern red-backed vole in the boreal forests of northern Canada

1. Across the vast boreal forests of North America, no population cycles in Clethrionomys species occur. In Eurasia, by contrast, some Clethrionomys populations of the same species undergo regular 3-5-year cycles. We examined the effects of nutrients, food, competitors, predators and climate on population limitation in the northern red-backed vole (Clethrionomys rutilus Pallas) in the south-western Yukon to determine why this difference occurs. 2. From 1986 to 1996 we added food, reduced large mammal predators and excluded snowshoe hares (Lepus americanus Erxleben) from large plots and found that none of these manipulations affected red-backed vole abundance. Adding nutrients as nitrogen, phosphorus and potassium (NPK) fertilizer had a slight negative effect, probably acting through a reduction in dwarf shrub productivity caused by competition from grasses. 3. We monitored weasel populations directly through trapping and indirectly through snow tracking. Predation by these vole specialists was irrelevant as a limiting factor most of the time because voles in this area do not reach the densities needed to sustain weasel populations. Other boreal forest mammal and bird predators did not focus on red-backed voles. However, when red-backed vole populations increased in the forest and Microtus voles also increased in the meadows, weasel populations increased and may have temporarily depressed red-backed voles in winter. 4. We monitored one major potential food, white spruce seeds, but seed fall was not related to population changes in red-backed voles, even after mast years. 5. We assessed the impact of weather variables, and the average depth of the snow pack during winter (October-March) was correlated directly with vole demography, having both direct effects in that year and delayed effects in the following year. 6. Our long-term trapping data (1973-96) indicate that Clethrionomys populations fluctuated, with peaks following hare peaks by 2-3 years. 7. We propose that the key variable limiting these vole populations is overwinter survival, and this is a function of overwinter food from berries produced during the previous summer by dwarf shrubs. These shrubs may be stimulated by abundant moisture from winter snows or by periodic fertilization from large quantities of pellets produced at snowshoe hare peaks.     

Description of Paranoplocephala yoccozi n. sp. (Cestoda: Anoplocephalidae) from the snow vole Chionomys nivalis in France, with a review of anoplocephaud cestodes of snow voles in Europe

We describe Paranoplocephala yoccozi n. sp. (Cestoda: Anoplocephalidae) from the snow vole Chionomys nivalis in Bourg-Saint-Maurice, French Alps, compare it with several related species from rodents, and review the anoplocephalid cestodes of snow voles in Europe. Paranoplocephala yoccozi n. sp. is primarily distinguished from the related species by its large scolex of characteristic shape, robust neck region, and the structure of the cirrus sac, vitellarium and vagina. We show that the anoplocephalid cestodes of snow voles in Europe, representing the genera Anoplocephaloides and Paranoplocephala, include at least seven species. This fauna consists primarily of species that snow voles share with other voles inhabiting the high-mountain areas. Some of the species, including P. yoccozi n. sp., appear to have a very localized distribution, which is assumed to be a consequence of the historical fragmentation of snow vole populations.     

Introduced Siberian chipmunks are more heavily infested by ixodid ticks than are native bank voles in a suburban forest in France

By serving as hosts for native vectors, introduced species can surpass native hosts in their role as major reservoirs of local pathogens. During a 4-year longitudinal study, we investigated factors that affected infestation by ixodid ticks on both introduced Siberian chipmunks Tamias sibiricus barberi and native bank voles Myodes glareolus in a suburban forest (Forêt de Sénart, Ile-de-France). Ticks were counted on adult bank voles and on adult and young chipmunks using regular monthly trapping sessions, and questing ticks were quantified by dragging. At the summer peak of questing Ixodes ricinus availability, the average tick load was 27-69 times greater on adult chipmunks than on adult voles, while average biomass per hectare of chipmunks and voles were similar. In adult chipmunks, individual effects significantly explained 31% and 24% of the total variance of tick larvae and nymph burdens, respectively. Male adult chipmunks harboured significantly more larvae and nymphs than adult females, and than juveniles born in spring and in summer. The higher tick loads, and more specifically the ratio of nymphs over larvae, observed in chipmunks may be caused by a higher predisposition - both in terms of susceptibility and exposure - to questing ticks. Tick burdens were also related to habitat and seasonal variation in age- and sex-related space use by both rodents. Introduced chipmunks may thus have an important role in the dynamics of local vector-borne pathogens compared with native reservoir hosts such as bank voles.     

The role of habitat barriers in woodlot recolonization by small mammals

The immigration and colonization of small mammals into a small depopulated wooded area surrounded by meadows was monitored by live-trapping and then compared with the same processes in an open forest following removal trapping. Rate of recolonization was lower in the depopulated woods than in the continuous forest. Bank voles, Clethrionomys glareolus , predominated the small mammal communities before removal; however, after removal the percentage of bank voles decreased and species diversity increased. When comparing the bank voles from the wooded area with the continuous forest, we found a higher percentage of sexually active animals, the lack of reproducing females and slightly lower body weights. Based on these characteristics the bank voles that recolonized the small woods were regarded as dispersers. The meadow belt surrounding the depopulated wood acted as a "filter" which stopped some bank voles and allowed others to pass through, and also "selected" different species crossing it according to their mobility. Some effects of such habitat barriers on the functioning of metapopulations are discussed.     

Structure of parasitic arthropod communities in forest small mammals

Species composition and structure of ectoparasite arthropod communities were examined all year round six years in the bank vole Clethrionomys glareolus, Ural wood mouse Apodemus uralensis and the common shrew Sorex araneus in forests of the Ilmen'-Volkhov depression. In total, 4500 host samples have been examined and all ectoparasites have been collected. The species composition of ectoparasite community in small mammal species are as follows: the bank vole--29 insect, tick and mite species, the common shrew--23 species, the Ural wood mouse--16 species. In forest biotopes, many temporary ectoparasitic species occur on several host species living in the same habitats under a forest canopy and contacting each other. A parasitic supracommunity in the ecosystem examined has a pool of temporary ectoparasites, which is available for all the community of small mammals. A role of different rodent and shrew species are hosts of insects and ticks changes depending on a density of potential host populations and numerous other environment factors.     

Harvest mites of the family Trombiculidae in the steppe zone of the southeastern Ukraine

Virgin and cultivated biotopes of the Sea of Azov area of Donetsk Province were investigated for parasite coenoses of small mammals. 469 animals and 210 nests were collected, Apodemus sylvaticus, Mus musculus, Microtus arvalis and Cricetulus migratorius being the most abundant species. In all 2940 larvae of trombiculids (18 species) were found on animals and in their nests (2846 specimens on animals and 94 specimens in nests). Two species, Hoffmannina theodori and Doloisia skljari, are new for science, the latter being the first find of the genus Doloisia member in the fauna of the USSR. The majority of parasites are collected from rodents inhabiting virgin biotopes (2328 specimens) while in cultivated biotopes 189 specimens were collected. More rich is the species composition of trombiculids in virgin biotopes (13 species) as compared to that in cultivated ones (5 species), Neotrombicula earis, N. japonica, N. autumnalis and N. vulgaris being mass species. 8 species of larvae are recorded from the nests of rodents. Seasonal dynamics of the abundance of mass species, their occurrence, index of abundance and infection intensity are shown.     

Molecular phylogeny of the speciose vole genus Microtus (Arvicolinae, Rodentia) inferred from mitochondrial DNA sequences

Voles of the genus Microtus represent one of the most speciose mammalian genera in the Holarctic. We established a molecular phylogeny for Microtus to resolve contentious issues of systematic relationships and evolutionary history in this genus. A total of 81 specimens representing ten Microtus species endemic to Europe as well as eight Eurasian, six Asian and one Holarctic species were sequenced for the entire cytochrome b gene (1140 bp). A further 25 sequences were retrieved from GenBank, providing data on an additional 23, mainly Nearctic, Microtus species. Phylogenetic analysis of these 48 species generated four well-supported monophyletic lineages. The genus Chionomys, snow voles, formed a distinct and well-supported lineage separate from the genus Microtus. The subgenus Microtus formed the strongest supported lineage with two sublineages displaying a close relationship between the arvalis species group (common voles) and the socialis species group (social voles). Monophyly of the Palearctic pitymyid voles, subgenus Terricola, was supported, and this subgenus was also subdivided into two monophyletic species groups. Together, these groupings clarify long-standing taxonomic uncertainties in Microtus. In addition, the "Asian" and the Nearctic lineages reported previously were identified although the latter group was not supported. However, relationships among the main Microtus branches were not resolved, suggesting a rapid and potentially simultaneous radiation of a widespread ancestor early in the history of the genus. This and subsequent radiations discernible in the cytochrome b phylogeny, show the considerable potential of Microtus for analysis of historical and ecological determinants of speciation in small mammals. It is evident that speciation is an ongoing process in the genus and that the molecular data provides a vital insight into current species limits as well as cladogenic events of the past.     

Characteristics of the distribution of Ixodes persulcatus in the forest-park area of Novosibirsk

Only one species of ixodid ticks Ixodes persulcatus occurs in the forest-park zone. Conditions of foliage forests with high grass, where occur hosts of all developmental phases of ticks (elks, hares, rodents, insectivores), are most favourable for I. persulcatus. Preimaginal phases of I. persulcatus feed, in general, on dominant species (common shrew, redbacked and narrow-skulled voles, field mouse and northern birch mouse).     

Host associations and origin in the formation of the Caucasian fauna of fleas (Siphonaptera)

Results of analysis of the Caucasian fauna of fleas and their association with mammal and avian hosts are reported. The Caucasian fauna of potential flea hosts comprises about 130 species of mammals and about 470 species of birds. Most of the flea species in the Caucasian fauna (88 out of 155) parasitize rodents, 51 species of which are permanent hosts of different flea species; 13 flea species occur on 11 species of insectivores; 13 flea species, on 13 species of chiropterans; 14 flea species, on 20 species of carnivores. Only 2 flea species parasitize artiodactyles. 54 species of birds are permanent hosts of 23 species of fleas from 4 genera in the Caucasus. Ten types of ranges of flea species are distinguished; host associations of the Caucasian flea species from these groups are discussed. The greatest numbers of hosts from the families Cricetidae, Muridae, and Sciuridae are associated with fleas with Euro-Asian (extra-Siberian), European, Turanian, and Iranian ranges. Soricidae are known as hosts of flea species with European and Euro-Turanian ranges. Four major groups of flea taxa are represented in the Caucasian fauna. The distribution of the first group is determined by the influence of the palaeofauna of the ancient European continent in the early Cenozoic; that of the second group, by the influence of the fauna of the ancient Asian continent during the Paleogene and part of the Neogene; the third, by the influence of the fauna of southern Europe starting with the Miocene. The fourth group comprises the species which immigrated from northern Europe and Asia in the Late Neogene (2–3 mln years ago).     

Systematics of snow voles (Chionomys, Arvicolinae) revisited

To elucidate the evolutionary history of snow voles, genus Chionomys, we studied the phylogeography of Chionomysnivalis across its range and investigated its relationships with two congeneric species, Chionomysgud and Chionomysroberti, using independent molecular markers. Analyses were based on mitochondrial (~940 bp cyt b) and Y-chromosomal (~2020 bp from three introns) genetic variation. Our data provide conclusive evidence for a Caucasian and Middle Eastern origin for the three species and a subsequent westward expansion of C.nivalis. In addition, we discuss the taxonomic status of the genus Chionomys in relation to the genus Microtus.     

Ecological ranges of plant species in the continental and ocean regions of Asian Russia

Exeplified by representatives of Poaceae of the flora of the Asian part of Russia, the ecological ranges of the plant species confined to coastal regions and of the species growing mostly within the continental regions (Inner Asia) have been compared. The comparison was made with respect to the ecological phytocenotic groups: coniferous and mixed forests, broad-leaved forests, meadows, communities of supralittoral zone, rocks, stony outcrops, and scree. Trends in the changes of the suite of indices of the ecological ranges of species that occur in the transition from continental climatic conditions of Inner Asia to monsoon climate of the Pacific coast have been revealed.     

The influence of spring floods on small mammal communities in the Nemunas River Delta, Lithuania

The influence of the annual spring floods on small mammal communities was studied in the Nemunas River Delta, SW Lithuania. The aim of the investigation was to compare the diversity of small mammals inhabiting spring-flooded meadows, meadows not subjected to flooding and spring-flooded forest in years characterized by differing heights and durations of spring flood. In the years of the high flood, the number of species and diversity index were higher, while index of dominance was less than in the years of low flood. Significantly, the highest proportions of Apodemus agrarius were recorded in spring-flooded meadows in years of high flood (41.7%), while Microtus oeconomus occurred in the highest proportions in spring-flooded meadows in years of low flood (66.8%) and in meadows not subjected to flooding (47.1%). In non-flooded areas, M. Oeconomus is not expelled by the floods and outcompetes other species. After high levels of flooding, during the process of re-population, the voles may be outcompeted by A. agrarius. In the absence of dominant species, greater opportunities existed for the establishment of more species (13 species in flooded meadows). Micromys minutus accounted for up to 19.5–30.1% in the years of high flood. We concluded that the annual spring floods in the Nemunas Delta had no long-term negative effects, the number of small mammal species and their abundance had been restored in just a few months. The worst consequences of the high flood were recorded in forest habitat. Spring floods, and especially the higher floods, are natural environmental agents, maintaining the high diversity of small mammals in meadows and reed-beds.     

Rare and threatened plant communitiesof Estonia

This paper introduces the criteria for identifying rare and threatened plant communities in Estonia. An overview of such communities is given and the general problems associated with their protection are briefly discussed. Of forest communities, alvar forests and boreo-nemoral forests must be preserved very carefully. Once widely distributed minerotrophic mobile-water swamp forests and flood plain forests nowadays cover only a small area. Numerous rare communities are associated with coastal regions and islands. Wooded meadows, the most species rich vascular plant communities in northern Europe, as well as flooded meadows and many other communities require continuation of traditional management for their preservation.