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1.
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Between 1960 and 2009, regular visits to Svalbard were made and a number of Hebeloma spp. were collected by several mycologists. We have studied 249 such collections, many from the Herbarium in Oslo (O) and from the private herbarium of the first author. The collections represent 17 different species. Of the 17 species, five (H. louiseae, H. pallidolabiatum, H. perexiguum, H. pubescens and H. spetsbergense) are only known from Svalbard. In this paper we discuss the habitat and apparent associates of the 17 species recorded, as well as their frequency of occurrence within our sample, and compare this with our data from other regions of the northern hemisphere. A further analysis compares the records we have from the collection of basidiomes with data published from root analysis of mycorrhizal associates on Svalbard. Root associate data strongly suggest the occurrence of an unknown Hebeloma species, not close to any of the infrageneric groups known to occur in arctic habitats.  相似文献   

3.
Despite a century long history of research, tardigrade fauna of the Svalbard Archipelago remains poorly known. In order to deepen our knowledge of tardigrade biodiversity in the Arctic, we collected forty-one moss and lichen samples from the Revdalen and on the south-east slopes of the Rotjesfjellet (Spitsbergen, Svalbard Archipelago) in June 2010. In these samples, twenty-five tardigrade species were found, including two new for science: Bryodelphax parvuspolaris sp. nov. and Isohypsibius coulsoni sp. nov. B. parvuspolaris sp. nov. belongs to the weglarskae group but differs from all other species of the group by a unique configuration of ventral plates. I. coulsoni sp. nov. differs from the most similar species I. ceciliae Pilato and Binda, 1987 mainly by the absence of ventral sculpture. Two additional species, Milnesium asiaticum Tumanov, 2006 and Diphascon (Adropion) prorsirostre Thulin, 1928, are recorded from the Svalbard Archipelago for the first time.  相似文献   

4.
The invertebrate fauna of the nests of three seabird species, black-legged kittiwakes (Rissa tridactyla), common eider (Somateria mollissima) and glaucous gull (Larus hyperboreus), were sampled in Kongsfjorden, Spitsbergen, Svalbard. The invertebrate community was species poor, consisting predominantly of the flea, Mioctenopsylla arctica arctica (Insecta: Siphonaptera), but with six species of oribatid mite (Acari: Oribatida), Diapterobates notatus, Oribatula tibialis, Ameronothrus lineatus, Hermannia reticulata, Trichoribates trimaculatus and Ceratoppia bipilis, plus an occasional mesostigmatid mite. No Collembola or ticks (Acari: Ixodidae) were observed. With the exception of M. arctica arctica, the fauna of seabird nests consisted of opportunistic microarthropod species rather than specialised nest-dwelling or bird parasitic species. Species diversity of soil oribatid mites was greater in nests of the common eider than compared to nests of the black-legged kittiwake, which may be related to the ground nesting behaviour of the common eiders. No rare or unusual microarthropod species for Svalbard were found in the seabird nests. The contentions that nests may facilitate microarthropod colonisation of High Arctic regions via bird phoresy by providing a high-quality habitat at the point of arrival, or that there might be a specialised microarthropod fauna exploiting this habitat, were not supported in this study. These are amongst the first data on the microarthropod community of seabird nests in the High Arctic.  相似文献   

5.
Fire management in protected areas requires an understanding of the consequences of fire regimes. Invertebrates are a key component of biological communities, but studies of fire impacts on diverse invertebrate assemblages over long timeframes are rare. The responses of ground- and foliage-active invertebrate assemblages to fire in buttongrass moorlands were investigated using a space-for-time design. Assemblages in recently burnt moorlands were distinct from those in older moorlands. Contrary to expectations, ground-active invertebrate abundance, but not taxon richness, was greatest in young regrowth (2–3 years since last fire), owing to large populations of Formicidae, Orthoptera, Collembola and Diptera. Foliage-active invertebrate assemblages followed the expected trend with least numbers of invertebrates and taxa in young regrowth. Very few taxa (n?=?9) were absent from young successional stages and none were absent from later successional stages. Invertebrate assemblages in moorlands on low productivity soils took approximately twice as long to return to their pre-fire state than assemblages on moderate productivity soils. The shifts in invertebrate composition were associated with shifts in vegetation composition. Vegetation density was found to be a potentially important predictor of invertebrate compositional variation. Fire in buttongrass moorland appears to have a limited impact on ground-active and foliage-active invertebrate assemblages, suggesting that these components of the invertebrate fauna are resilient to fire (i.e. able to return to the pre-fire state). Given that fire impedes successional processes that convert moorlands into rainforest, and eliminate many of the moorland invertebrate species, conservation management of moorlands should involve the acceptance or imposition of fire.  相似文献   

6.
Six polymorphic microsatellites were developed for the caddisfly Plectrocnemia conspersa from two enriched partial genomic libraries. These represent the first microsatellites published for the order Trichoptera. We show that, whilst it is possible to develop a highly enriched library, isolation of polymorphic microsatellites is difficult for this species, as has been found in some other of invertebrate groups. The genotypes of 160 individuals were determined using these new loci. Observed heterozygosities ranged from 0.013 to 0.788. Despite their problematic isolation, polymorphic microsatellite loci show greater levels of variation than previously studied allozyme markers.  相似文献   

7.
No less than 52 species of barbets have been imported and kept in German zoos during the period between 1960 and 2000. In the first years some (world) first breeding records came from several zoos, Frankfurt with six world first records as the most successful one. Today only two species, the Bearded Barbet (Lybius dubius) and the Red-and-yellow Barbet (Trachyphonus erythrocephalus), breed regularly in ten respectively 14 German zoos and bird parks. The majority of the other species have been lost since, e.g. for future breeding projects. There are also some records of successful broods of barbets in private facilities, but the two species mentioned above are also on top of the list of the breeding records. The problems of keeping and breeding barbets in captivity, their life span, diseases and adequate housing conditions are compiled from data of the literature.  相似文献   

8.
The harsh climate and patchy distribution of habitable terrestrial ecosystems constrain soil invertebrate communities in continental Antarctica. The Windmill Islands in East Antarctica have a relatively gentle climate by Antarctic standards, and the region supports some of the most well-developed moss beds on the continent. These moss beds and soils are known to sustain invertebrate communities dominated by nematodes, rotifers and tardigrades, but our knowledge of the diversity and composition of these communities remains limited. We extracted soil fauna from 74 soil samples representing a wide range of microhabitats, and 24 moss samples, collected at Clark Peninsula, Bailey Peninsula and Robinson Ridge in the Windmill Islands during the 2012–2013 austral summer. Invertebrates were present in all samples, but densities varied considerably both within and between sites with limited correlation with edaphic variables or cover type. Taxa found included two species of nematodes (Plectus murrayi; Plectus frigophilus), one mite (Nanorchestes antarcticus) as well as tardigrades and rotifers (enumerated only). No springtails were found in this study, but individuals of the genus Cryptopygus were later recovered from moss collected near Casey Station. The Windmill Islands soils and moss beds support dense populations of soil fauna. However, despite the relatively mild climate conditions and favorable soil properties, species diversity is low. The diversity is possibly limited by recent deglaciation and limited dispersal opportunities to the region. Given favorable local conditions, it is likely that colonizing species will perform well, whether these arrive by natural means or are accidentally introduced by humans.  相似文献   

9.
Invertebrate species carried incidentally (i.e., ‘hitchhikers’) in the aquarium trade have gained increasing attention in recent years, but factors affecting the movement of species from stores to homes are poorly understood. We aimed to determine how macrophytes bought from stores act as vectors for transport of non-indigenous invertebrate species. We tested whether incidental invertebrate faunas carried on macrophytes vary internationally by comparing the New Zealand and Canadian trades, and if macrophyte species with different morphologies carry different risks. We recorded a large variety of invertebrate species associated with Vallisneria spp., Sword plants (Echinodorus spp.) and Elodea canadensis bought from stores, including species non-indigenous to both countries. Community composition of incidental fauna differed significantly between New Zealand (primarily domestically cultivated) and Canadian (primarily imported) bought macrophytes. Differences in composition between different macrophyte species were only statistically significant between wild-collected E. canadensis and the cultured species in New Zealand. Behaviours observed in stores, such as the amount of time macrophytes were removed from water before being placed in plastic bags for transport, did not affect the abundances or richness of incidental invertebrates transported, and thus did not appear to be effective in reducing invasion risk. We therefore recommend chemical treatment for removal of invertebrates from macrophytes at or pre-border, and from tanks containing plants at culture facilities and in stores. Such management will reduce the probability of introduction of hitchhikers to home aquaria, from which risk of release to natural waters is greatest.  相似文献   

10.
11.
The genus Longidorus includes a remarkable group of invertebrate animals of the phylum Nematoda comprising polyphagous root-ectoparasites of numerous plants including several agricultural crops and trees. Damage is caused by direct feeding on root cells as well as by transmitting nepoviruses that cause disease on those crops. Thus, correct identification of Longidorus species is essential to establish appropriate control measures. We provide the first detailed information on the diversity and distribution of Longidorus species infesting wild and cultivated olive soils in a wide-region in southern Spain that included 159 locations from which 449 sampling sites were analyzed. The present study doubles the known biodiversity of Longidorus species identified in olives by including six new species (Longidorus indalus sp. nov., Longidorus macrodorus sp. nov., Longidorus onubensis sp. nov., Longidorus silvestris sp. nov., Longidorus vallensis sp. nov., and Longidorus wicuolea sp. nov.), two new records for wild and cultivate olives (L. alvegus and L. vineacola), and two additional new records for wild olive (L. intermedius and L. lusitanicus). We also found evidence of some geographic species associations to western (viz. L. alvegus, L. intermedius, L. lusitanicus, L. onubensis sp. nov., L. vineacola, L. vinearum, L. wicuolea sp. nov.) and eastern distributions (viz. L. indalus sp. nov.), while only L. magnus was detected in both areas. We developed a comparative study by considering morphological and morphometrical features together with molecular data from nuclear ribosomal RNA genes (D2–D3 expansion segments of 28S, ITS1, and partial 18S). Results of molecular and phylogenetic analyses confirmed the morphological hypotheses and allowed the delimitation and discrimination of six new species of the genus described herein and four known species. Phylogenetic analyses of Longidorus spp. based on three molecular markers resulted in a general consensus of these species groups, since lineages were maintained for the majority of species. This study represents the most complete phylogenetic analysis for Longidorus species to date.  相似文献   

12.
Microbial processing of detritus is known to be important to benthic invertebrate nutrition, but the role of dissolved (DOC) versus particulate organic carbon (POC), and pathways by which those resources are obtained, are poorly understood. We used stable isotopes to determine the importance of DOC, POC, and CH4-derived carbon to benthic invertebrate consumers from arctic Alaskan Lakes. Intact sediment cores from Lake GTH 112 were enriched with 13C-labeled organic matter, including algal detritus, algal-derived DOC, methyl-labeled acetate, and carboxyl-labeled acetate, and incubated for 1?month with either caddisflies (Grensia praeterita ) or fingernail clams (Sphaerium nitidum), two invertebrate species that are important to fish nutrition. Both species used basal resources derived from POC and DOC. Results generally suggest greater reliance on POC. Differential assimilation from acetate treatments suggests Sphaerium assimilated CH4-derived carbon, which likely occurred through deposit-feeding. Grensia assimilated some microbially processed acetate, although its survivorship was poor in acetate treatments. Our data extend previous studies reporting use of CH4-derived carbon by Chironomidae and oligochaetes. Taken together, these results suggest that the use of CH4-derived carbon is common among deposit-feeding benthic invertebrates.  相似文献   

13.
Cysticerci of Taenia sp. from two elks (Alces alces) in Finland were characterized using morphological criteria and sequences of two mitochondrial DNA regions. The host species, size, structure and location of the cysticerci indicated that they might belong to Taenia krabbei, a circumpolar species occurring in a sylvatic life cycle in wild canids and cervids. Based on the number, length and shape of the rostellar hooks, the specimens could not be unambiguously defined as belonging to T. krabbei, T. cervi, T. ovis or T. solium. In the phylogenetic analysis, based on mitochondrial nucleotide sequence data, Taenia sp. was placed as a sister species of T. solium, distant from T. krabbei isolates previously characterized from Svalbard. This indicates that the Finnish and the Svalbard isolates, resembling T. krabbei, cannot represent a single species. The results suggest that careful morphological and genetic analyses of further isolates from intermediate and definitive hosts are required to define the taxonomic status of these two cryptic species.  相似文献   

14.
Eighteen species of eleven lichen genera were found on driftwood and worked timber deposited on the beaches in the Hornsund and Billefjorden regions (the west coast of Spitsbergen, Svalbard archipelago). Majority of them indicate low substrate specificity in the high arctic regions. Only three species (Caloplaca spitsbergensis, Lecanora mughicola, L. orae-frigidae) are typical for lignum. Most of the taxa are widespread in Svalbard. Species like: Caloplaca holocarpa, C. spitsbergensis, Protothelenella sphinctrinoidella, Rinodina archaea were sporadically reported till now. Lecanora mughicola was not reported from Svalbard up to the present and this is the first record of the species for the region.  相似文献   

15.
This article presents the first compilation of marine non-indigenous species (NIS) of algae and macro-invertebrates invading Chilean waters. A total of 32 cosmopolitan and non-cosmopolitan species are reported. Among them there are six species considered as extending their southern range of distribution in connection with El Niño events. The article highlights negative and positive impacts caused by marine NIS invasions. Among the first are Codium fragile var. tomentosoide, considered as a pest in Gracilaria chilensis aquaculture facilities in northern Chile, and Ciona intestinalis, a pest in scallop aquaculture installations. Among the second are bio-engineers species, such as the ascidian Pyura praeputialis and the sea grass Heterozostera tasmanica, which have caused an increase in local biodiversity and enhancement of nursery grounds via the creation of new habitats. Further more, invaders such as the algae Mastocarpus papillosus, Porphyra linearis and P. pseudolinearis represent new exploitable resources, extracted by coastal food gatherers along the coast (M. papillosus) or potential species to develop aquaculture. Additional information is presented on the anemone Anemonia alicemartinae, which appears to be a native species (?), having shown in the past 40–50 years, a geographical southward range extension of approximately 1900 km. The number of NIS reported for Chile is compared with those published for the southwestern Atlantic, South Africa, North America (Atlantic and Pacific coasts) and New Zealand. It is suggested that probably the low number of Chilean NIS is due to the fact that the Chilean coasts are environmentally less stressed than other coasts in the world, due to the scarcity of estuaries, gulfs, enclosed bays, lagoons and low human populations. These kinds of sheltered areas have been suggested as centers for bio-invasions, due to the high rate of human-mediated transfer and increase of pollutants. Furthermore, none of NIS reported from Chile show a fast geographical expansion rate (exception of A. alicemartinae), nor invading strategies such as those described for marine NIS in other latitudes, where notorious ecological unbalances following invasions have been observed. An alternative hypothesis is that the low number of marine NIS invading Chile is underestimated, since the modern list of species generated through specific taxonomically intensive port and harbor surveys is still lacking. Fifteen species (five invertebrate and 10 fish) have been deliberately imported to Chile for aquaculture. The invertebrates appear to be controlled within aquaculture facilities and have not established naturalized populations or caused direct ecological impacts on local communities. On the contrary, several millions of salmoniforms (and rainbow trout) have escaped from farming facilities in southern Chile and established naturalized populations. Studies on ecological impacts are lacking. These escapees are also playing a role in the enhancement of artisanal and sport fishery activities.  相似文献   

16.
In recent years, there have been frequent reports of invertebrate species newly recorded from particular areas of the Northeastern Atlantic, and it has often been suggested that these are the result of changes in species ranges due to recent warming. These suggestions make three assumptions: (1) that we have a good knowledge of the fauna of these areas; (2) that new records of “southern” species are more frequent than new records of “northern” species; (3) that climate change is the only factor affecting species range. I tested these assumptions on published records of 30 benthic molluscan species which have been found alive for the first time in the Russian part of the Barents Sea since 2006. Some of the discussed species are warm-water species and may have extended their ranges northward in response to climate change. However, our baseline knowledge of the molluscan fauna of this area before 2006 is limited by the frequent lack of molluscan specialists to study the available material, by the frequent lack of detailed publication and by changes in sampling and processing methods. New records of “southern” species are in fact not significantly commoner than new records of “northern” species. Also reasons other than climate change for observed changes in species distribution should be considered.  相似文献   

17.
Cryoconite holes on glacier surfaces are ice-cold hot spots of microbial diversity and activity but still little is known about their fungal inhabitants. We provide the first report of distinctive fungal communities in cryoconite debris from three valley glaciers at Kongsfjorden, Svalbard. Multivariate analysis of terminal-restriction fragment length polymorphism (T-RFLP) profiles of rRNA ITS amplicons revealed that quite distinct fungal communities were found in cryoconite holes compared with soils from adjacent moraine and tundra sites, and that communities on glaciers with contrasting ice-surface hydrology also differed. Most of the fungi cultured from cryoconite sediment were basidiomycetous yeasts or filamentous Ascomycota (Helotiales/Pleosporales). The latter included aeroaquatic fungi, such as Articulospora and Varicosporium, implying a role for these important freshwater decomposers in the carbon dynamics of cryoconite holes. Matching of the dominant peaks from T-RFLP analysis to predicted peaks of cultured isolates confirmed the abundance of these aeroaquatic fungi but also revealed that most of the dominant T-RFLP peaks did not match any cultured isolates. Considering the prevalence and endangerment of glacial environments worldwide, these findings would suggest that their potential as reservoirs of fungal diversity should not be overlooked.  相似文献   

18.
Parasite diversity above the Arctic circle remains understudied even for commercially valuable host taxa. Thorny skate, Amblyraja radiata, is a common bycatch species with a growing commercial value. Its natural range covers both sides of the North Atlantic including the Arctic zone. Svalbard is a Norwegian archipelago located on the northwest corner of the Barents Shelf which sustains a spectacular species diversity. So far, several monogenean species have been reported infecting thorny skate across the Atlantic Ocean. In the present study, we intend to fill in the knowledge gap on monogenean parasites infecting thorny skate in the northern part of its range and thus indirectly assess the connectivity between the thorny skate populations off the Svalbard coast and from previously studied locations. 46 monogenean individuals were recovered from 11 specimens of thorny skate. Following morphological and molecular assessment, two species of monogeneans, Acanthocotyle verrilli and Rajonchocotyle emarginata, were identified. The results serve as the northernmost record for both parasite genera and the first record of monogenean species off Svalbard. Detailed morphometric evaluation revealed a relatively high level of morphological variation in A. verrilli compared to its congeners. Phylogenetic reconstruction placed A. verrilli in a well-supported clade with A. imo. Our study also suggests high diagnostic significance of sclerotised structures in the identification of Rajonchocotyle. Even though the occurrence of two directly transmitted parasite species supports the previously suggested long-distance migration of A. radiata, future studies employing highly variable genetic markers are needed to assess the ongoing and historical migration patterns.  相似文献   

19.
In recent years 4 species of the genusEchinodorus have been imported in large quantities to Europe from Southern Brazil, being cultivated as decorative plants in aquaria. In spite of the fact that up to now not all organs from these plants are known, they differ so greatly from the known species by character of the submersed leaves that there is no doubt that the species, in question, viz.E. osiris, E. opacus, E. horemani andE. portoalegrensis, are new.  相似文献   

20.
It is known that the microbial community of the rhizosphere is not only influenced by factors such as root exudates, phenology, and nutrient uptake but also by the plant species. However, studies of bacterial communities associated with tropical rainforest tree root surfaces, or rhizoplane, are lacking. Here, we analyzed the bacterial community of root surfaces of four species of native trees, Agathis borneensis, Dipterocarpus kerrii, Dyera costulata, and Gnetum gnemon, and nearby bulk soils, in a rainforest arboretum in Malaysia, using 454 pyrosequencing of the 16S rRNA gene. The rhizoplane bacterial communities for each of the four tree species sampled clustered separately from one another on an ordination, suggesting that these assemblages are linked to chemical and biological characteristics of the host or possibly to the mycorrhizal fungi present. Bacterial communities of the rhizoplane had various similarities to surrounding bulk soils. Acidobacteria, Alphaproteobacteria, and Betaproteobacteria were dominant in rhizoplane communities and in bulk soils from the same depth (0–10?cm). In contrast, the relative abundance of certain bacterial lineages on the rhizoplane was different from that in bulk soils: Bacteroidetes and Betaproteobacteria, which are known as copiotrophs, were much more abundant in the rhizoplane in comparison to bulk soil. At the genus level, Burkholderia, Acidobacterium, Dyella, and Edaphobacter were more abundant in the rhizoplane. Burkholderia, which are known as both pathogens and mutualists of plants, were especially abundant on the rhizoplane of all tree species sampled. The Burkholderia species present included known mutualists of tropical crops and also known N fixers. The host-specific character of tropical tree rhizoplane bacterial communities may have implications for understanding nutrient cycling, recruitment, and structuring of tree species diversity in tropical forests. Such understanding may prove to be useful in both tropical forestry and conservation.  相似文献   

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