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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. [ABSTRACT FROM AUTHOR]

The nematode Pristionchus pacificus is of growing interest as a model organism in evolutionary biology. However, despite multiple studies of its genetics, developmental cues, and ecology, the basic life-history traits (LHTs) of P. pacificus remain unknown. In this study, we used the hanging drop method to follow P. pacificus at the individual level and thereby quantify its LHTs. This approach allowed direct comparisons with the LHTs of Caenorhabditis elegans recently determined using this method. When provided with 5×109 Escherichia coli cells ml–1 at 20°C, the intrinsic rate of natural increase of P. pacificus was 1.125 (individually, per day); mean net production was 115 juveniles produced during the life-time of each individual, and each nematode laid an average of 270 eggs (both fertile and unfertile). The mean age of P. pacificus individuals at first reproduction was 65 h, and the average life span was 22 days. The life cycle of P. pacificus is therefore slightly longer than that of C. elegans, with a longer average life span and hatching time and the production of fewer progeny. [ABSTRACT FROM AUTHOR]

Global transformations extend beyond local habitats; therefore, larger-scale approaches are needed to assess community-level responses and resilience to unfolding environmental changes. Using long-term data (1996-2011), we evaluated spatial patterns and functional redundancies in the littoral invertebrate communities of 85 Swedish lakes, with the objective of assessing their potential resilience to environmental change at regional scales (that is, spatial resilience). Multivariate spatial modeling was used to differentiate groups of invertebrate species exhibiting spatial patterns in composition and abundance (that is, deterministic species) from those lacking spatial patterns (that is, stochastic species). We then determined the functional feeding attributes of the deterministic and stochastic invertebrate species, to infer resilience. Between one and three distinct spatial patterns in invertebrate composition and abundance were identified in approximately one-third of the species; the remainder were stochastic. We observed substantial differences in metrics between deterministic and stochastic species. Functional richness and diversity decreased over time in the deterministic group, suggesting a loss of resilience in regional invertebrate communities. However, taxon richness and redundancy increased monotonically in the stochastic group, indicating the capacity of regional invertebrate communities to adapt to change. Our results suggest that a refined picture of spatial resilience emerges if patterns of both the deterministic and stochastic species are accounted for. Spatially extensive monitoring may help increase our mechanistic understanding of community-level responses and resilience to regional environmental change, insights that are critical for developing management and conservation agendas in this current period of rapid environmental transformation. [ABSTRACT FROM AUTHOR]

We investigated differences in the abundance, community composition and taxon richness of sublittoral macroinvertebrates in boreal lakes containing introduced invasive signal crayfish ( Pacifastacus leniusculus) or native noble crayfish ( Astacus astacus). We hypothesised that sublittoral macroinvertebrate assemblages in lakes containing noble crayfish, which reportedly prefer the shallow littoral, would differ little from those in lakes without crayfish, in contrast to assemblages in lakes containing signal crayfish, which reportedly forage at greater depths., In a set of 24 small and medium-sized Finnish lakes, eight lakes contained signal crayfish, eight had noble crayfish and eight control lakes had no crayfish. At three sites per lake, we sampled macroinvertebrates quantitatively from soft sediment in the sublittoral., The sublittoral macroinvertebrate assemblage in lakes with noble crayfish and control lakes was similar. In contrast, lakes with signal crayfish had a lower density of Trichoptera and Ephemeroptera, as well as a lower density and species richness of Chironomidae, and a lower overall benthic density and taxon richness., In contrast to some previous reports from other habitats, we infer that introduced signal crayfish have stronger negative effects than native noble crayfish on sublittoral macroinvertebrates. Hence, the ecological equivalence or differences of crayfish species cannot be generalised across habitats. [ABSTRACT FROM AUTHOR]

While swimming in their natural environment, marine organisms must successfully forage, escape from predation, and search for mates to reproduce. In the process, planktonic organisms interact with their fluid environment, generating fluid signatures around their body and in their downstream wake through ontogeny. In the early stages of their life cycle, marine organisms operate in environments where viscous effects dominate and govern physical processes. Ontogenetic propulsive transitions in swimming organisms often involve dramatic changes in morphology and swimming behavior. However, for organisms that do not undergo significant changes in morphology, swimming behavior or propulsive mode, how is their swimming performance affected? We investigated the ontogenetic propulsive transitions of the hydromedusa Sarsia tubulosa, which utilizes jet propulsion and possesses a similar bell morphology throughout its life cycle. We used digital particle image velocimetry and high-speed imaging to measure the body kinematics, velocity fields and wake structures induced by swimming S. tubulosa with bell exit diameters from 1 to 10 mm. Our experimental observations revealed three distinct classes of hydrodynamic wakes: elongated vortex rings for 1030 (larger than 2 mm bell exit diameter) and elliptical vortex rings (or leading vortex rings) followed by trailing jets for most instances where Re>100 (larger than 4 or 5 mm bell exit diameter). The relative travel distance and propulsive efficiency remained unchanged throughout ontogeny, and the swimming proficiency and hydrodynamic cost of transport decreased non-linearly. [ABSTRACT FROM AUTHOR]

Effective water resources assessment and management requires quantitative information on the variability of ambient and biological conditions in aquatic communities. Although it is understood that natural systems are variable, robust estimates of long-term variation in community-based structure and function metrics are rare in U.S. waters. We used a multi-year, seasonally sampled dataset from multiple sites ( n = 5-6) in four streams (Codorus Creek, PA; Leaf River, MS; McKenzie and Willamette Rivers, OR) to examine spatial and temporal variation in periphyton chlorophyll a, and fish and macroinvertebrate metrics commonly used in bioassessment programs. Within-site variation of macroinvertebrate metrics and benthic chlorophyll a concentration showed coefficient of variation ranging from 16 to 136 %. Scale-specific variability patterns (stream-wide, season, site, and site-season patterns) in standardized biotic endpoints showed that within-site variability patterns extended across sites with variability greatest in chlorophyll a and lowest in Hilsenhoff's Biotic Index. Across streams, variance components models showed that variance attributed to the interaction of space and time and sample variance accounted for the majority of variation in macroinvertebrate metrics and chlorophyll a, while most variation in fish metrics was attributed to sample variance. Clear temporal patterns in measured endpoints were rare and not specific to any one stream or assemblage, while apparent shifts in metric variability related to point source discharges were seen only in McKenzie River macroinvertebrate metrics in the fall. Results from this study demonstrate the need to consider and understand spatial, seasonal, and longer term variability in the development of bioassessment programs and subsequent decisions. [ABSTRACT FROM AUTHOR]

The Los Tuxtlas Biosphere Reserve in Southeastern Veracruz, Mexico represents the northernmost Neotropical lowland rainforest and has lost 84 % of its forests in the last forty years. Rich terrestrial and aquatic species communities are found throughout Neotropical forests, habitats increasingly threatened by land management practices. Plant-held waters, phytotelmata, are ecologically important discrete microhabitats harboring many specialist invertebrates and are abundant in tropical forests. In this study, using artificial tree holes, we examined invertebrate tree hole communities in a mature forest of Los Tuxtlas and in a managed habitat adjacent to the Los Tuxtlas Biological Station. Based on the proximity of human and livestock communities to managed habitats and the dispersal limitations of some phytotelmata specialists, we expected to find community composition differences between the two habitats. We found distinct differences in chironomid colonization; Tanypodinae, a predaceous subfamily, was present in the managed habitat and its omnivorous counterpart, Chironominae, was present in the forest. We found differences in mosquito colonization with more predaceous Toxorhychites in the managed habitat. Haemagogus mosquitoes were only present in the managed habitat. These results indicate different colonization ability across phytotelmata specialists and warn of larger community shifts and potential public health hazards with continued and intensified forest fragmentation and degradation. [ABSTRACT FROM AUTHOR]

Frequent blooms of the giant jellyfish, Nemopilema nomurai, have occurred in the East Asian Marginal Seas since 2000 and have had a devastating effect on commercial fisheries. To determine the probability of future bloom development to permit effective countermeasures, it is essential to assess the influence of environmental factors on polyp development. In this study, the effects of salinity on the polyps of N. nomurai from the coastal waters of Dalian in the northern Yellow Sea were tested at salinities ranging from 2.5 to 45. The combined effects of salinity (15 and 32) and light intensity (800, 400, and 0 lux) in a 12-h light-12-h dark photoperiod were also assessed. The lower and upper salinity limits for N. nomurai polyp survival were 10 and 40, respectively. The salinity range of 20-27.5 was best for podocyst reproduction. Survival and somatic growth of polyps, and their asexual production of podocysts, were significantly greater at low to middle than at high salinities. Polyps survived, grew, and produced podocysts at all light intensities tested; however, differences in light intensity induced few statistically significant changes. These results indicated that N. nomurai polyps are adapted to survive, grow, and reproduce in estuaries and near-shore environments. [ABSTRACT FROM AUTHOR]

The order Strophomenida was an ecologically abundant and taxonomically diverse group of Palaeozoic brachiopods that originated in the earliest Ordovician and went extinct in the Carboniferous. During their long geological range, the Strophomenida survived two of the ' Big Five' mass extinction events, the Late Ordovician and the Late Devonian, suggesting that they are potentially informative taxa for studying the evolutionary effects of these two distinct mass extinctions, each with drastically different forcing mechanisms. However, while there have been previous phylogenetic studies on smaller groups within the Strophomenida, the phylogenetic relationships of the whole group are still largely unknown. The group has been divided into two major superfamilies, the Strophomenoidea (strophomenoids) and the Plectambonitoidea (plectambonitoids). Despite being treated as separate clades, the plectambonitoids may form a paraphyletic grade into the strophomenoids. We present a detailed higher-level parsimony-based phylogenetic analysis of the Strophomenida, consisting of 69 characters and 62 exemplar species sampled from the majority of the taxonomically defined families/subfamilies. Several species of basal chonetids (strophochonetids) were also included in this analysis, as they may be closely related to the Strophomenida and share several characters with both the plectambonitoids and strophomenoids. The phylogenetic analysis suggests the plectambonitoids, as originally defined, are paraphyletic to the monophyletic strophomenoids. The basal chonetids are reconstructed as a monophyletic group that is sister to the strophomenoids, suggesting that their proper placement might be within the Strophomenida. The topology also suggests that at least 17 of the taxonomically defined strophomenoid and plectambonitoid families are likely to be monophyletic. The Plectambonitidae and the Taffiidae as defined are paraphyletic, and the Grorudiidae and Leptostrophiidae are polyphyletic. Furthermore, subfamilies Leptodontellinae, Dicoelostrophiinae, Palaeostrophomeninae and Aegiromeninae are raised to the level of family. When analysed within this phylogenetic context, the Late Ordovician mass extinction event had little effect on the large-scale evolution of the group. [ABSTRACT FROM AUTHOR]

Lotic ecosystems are highly affected by land use changes such as afforestation of natural areas for management or commercial purposes. The aim of this study was to analyze the effect of pine plantations on benthic invertebrate communities in mountain grassland streams. Additionally, we assessed if the hydrological period modifies the effect of afforestation on stream invertebrates. Three headwater streams draining grasslands (reference streams) and three draining plantations of Pinus elliottii were selected in a mountain watershed of Córdoba province (Argentina). Hydrologic and physicochemical variables were registered and benthic invertebrate samples were collected in each stream at two different hydrological periods. Total invertebrate abundance, richness and diversity were reduced in afforested streams as well as the number of indicator taxa. In addition, invertebrate functional structure (i.e. taxonomic richness and total and relative abundance of functional feeding groups, FFG) showed differences between streams with different riparian vegetation and between hydrological periods. Total abundance of all FFGs was lower in afforested streams and scrapers’ relative abundance was higher in grassland streams at the low water period. In addition, in most FFGs richness was diminished in afforested streams. Changes in light intensity, hydrology and coarse organic matter inputs produced by afforestation alter fluvial habitats and consequently the composition and trophic structure of invertebrate communities in grassland streams of Córdoba mountains. [ABSTRACT FROM AUTHOR]

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Invertebrate herbivores, insects in particular, play important functional roles in terrestrial ecosystems. At background (non-outbreak) densities, they consume 5-15 % of woody plant foliage in forests across the planet. At the same time, almost nothing is known about the levels of insect herbivory in Arctic tundra. To test the hypothesis that the amount of plant biomass lost to insects in tundra is substantially less than in subarctic forests, in 2013, we explored foliar herbivory in woody plants at three sites in the Arctic tundra and four sites in the subarctic forests of European Russia. A vast majority of foliar damage was imposed by externally feeding defoliators. In forests, defoliators damaged three times more leaves and consumed eight times more leaf area than in the tundra. No miners were found in the tundra, and gallers affected five times less leaf area in the tundra compared with forests. An abrupt decrease in loss of woody plant foliage to insects between subarctic forests and tundra (from 4.34 to 0.56 %) supports the existence of a latitudinal gradient in herbivory in terrestrial ecosystems. More studies are needed to predict how tundra plants, which have been historically exposed to low levels of insect herbivory, will cope with the increased levels of damage that are expected to occur due to climate-driven range expansion and increased abundances of plant-feeding insects. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) emission of fresh invertebrates has too long been neglected in eutrophic lakes, although the sediments these animals inhabit are presumably hot spots of N2O emission. Thus, the experiment in this research was designed to gain insight into the influence of cyanobacterial degradation on the N2O emission by fresh water invertebrates (Chironomus plumosus). The presence of decaying cyanobacteria in Lake Taihu decreased the N2O emission rate of Chironomus plumosus larvae from the larvae body by almost 400% for the larvae as a whole. The N2O emission rate decreased by 350% based on readings from studies of their gut, which was mostly due to stimulation of intestinal complete denitrification. The quantitative PCR results showed that intestinal gene abundance of nirK, nosZ (encoding the copper nitrite reductase and N2O reductase, respectively) were significantly increased with the presence of decaying cyanobacteria. In contrast nirS (encoding the cytochrome cd1 heme nitrite reductase) and the total bacteria decreased. In the gut of Chironomus plumosus, the diversity and richness of nosZ and nirK were lower with the cyanobacteria. Phylogenetic analysis of the intestinal function genes (nosZ and nirK) showed that the nosZ- and nirK-type denitrifying bacterial sequences were related to different phylotypes. Hence, additional cyanobacteria increased the abundance, but decreased the richness and diversity of intestinal nitrate- reducing bacteria, probably by providing more carbon source in the gut. The data obtained in this study elucidates that the decaying cyanobacteria decreased the emissions of N2O by the aquatic invertebrates in freshwater sediment and could serve as a valuable resource for nitrogen removal affecting greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Taxonomic and ecological aspects of paralarval octopods from the Florida Current (Gulf Stream) waters off Fort Pierce, Florida are reported. Nine external morphological features were analysed in each specimen, including chromatophore patterns and meristic characters. The relative abundance of each species present in the collections made at standard stations [2–26 nautical miles (nmi) offshore at 2-nmi intervals; 1 nmi = 1.8520 km] was determined in relation to seasonal occurrence, depth of capture, distance offshore and time of day/night. The most common species in the samples wasOctopus“vulgaris”, followed byAmphioctopus burryiandMacrotritopus defilippi(two morphs). Two forms could not be verified to species, but they most closely resembleScaeurgus unicirrhusand “Octopus”joubini. The seasonal distribution of the most commonly captured species showed peak relative abundance in the summer months. Paralarval octopods were captured most frequently in the standard stations between 18 and 22 nmi (29.6–40.7 km) offshore in the mid-depth stratum of the water column. Most of the species represented in this study were captured in higher numbers at night than during the day, with the exception ofA. burryi. [ABSTRACT FROM AUTHOR]

Freshwater macroinvertebrates face numerous stressors at different spatial scales, challenging river managers to identify the most appropriate, to initiate a successful river restoration. To address this, 45 samples from 13 sites located in a regulated and temporary Mediterranean river network were analyzed. Sites were separated according to hydrology and classified into four zones based on land use. Chemical analysis was undertaken prior to macroinvertebrate sampling, and a chemo-biological classification was performed. Canonical correspondence analysis (CCA) and analysis of similarities were used to identify statistical differences between the various groups. Unacceptable quality according to the Water Framework Directive 2000/60/EC was revealed for 60% of samples. Significant correlations were detected between land use and biological indices. Agriculture was the major factor influencing macroinvertebrate distribution, and significant taxonomic differences were identified between natural and agriculturally impacted sites. Flow regime alterations from water regulation and desiccation resulted in significant reduction in macroinvertebrate density. The small difference between explained/unexplained variance (45%/55%, CCA) suggests that land use and local in-stream factors together influence macroinvertebrate assemblages. We conclude that in regulated/temporary rivers, land use and flow-related pressures exert strong influence on freshwater invertebrates and should be given equal importance as local in-stream factors, for sustainable river restoration. [ABSTRACT FROM AUTHOR]

This study presents the development of a multimetric index using benthic macroinvertebrates (BMI) to assess the ecological health of highland rivers in Ethiopia. BMI were collected from 22 reference and 82 impaired sites determined based on hydro-morphological, land use, and physical and chemical criteria. Of 75 potential metrics tested to integrate the multimetric index, only nine core metrics were selected based on their abilities to distinguish reference and impaired sites, strength of correlation with pertinent environmental parameters, and their independence from other metrics. The metrics retained in the multimetric index were total number of taxa, EPT-BH > 1sp (Ephemeroptera, Plecoptera, and Trichoptera taxa where Baetidae and Hydropsychidae taxa are considered if they consist more than one taxon), % Oligochaeta and Red Chironomidae, % COPTE (Coleoptera, Odonata, Plecoptera, Trichoptera, and Ephemeroptera), % EPT-BCH (EPT without Baetidae, Caenidae, and Hydropsychidae), ASPT-SASS (Average South African Scoring System Per Taxa), FBI (Family Biotic Index), % shredders, and % collector gathering. The final index derived from these metrics was divided into five river quality class (high, good, moderate, poor, and bad). A validation procedure showed that the index is stable along different hydrological conditions and sensitive to the current range of anthropogenic disturbances in Ethiopian highland rivers. [ABSTRACT FROM AUTHOR]

The new method of biological assessment in flowing waters-NoMBSI (Non-lethal Method for Benthos Sampling and Identification) is presented. To determine the amount of information (informativity), which is possible to obtain during a sample analysis, the results of three procedures were compared (NM-the new one based on 3D digital image analysis, NC-control procedure based on microscopic identification and G, which is the traditional method based on samples collected with Günther sampler). Procedures were applied for the samples collected at 27 sites in North-eastern and Eastern Poland. The NM was found to provide for the correct recognition of an average of 45% of taxa present in samples. Taxa of small size and lower abundance were frequently failed to be identified. However, no significant differences between NM and NC in terms of raw data on taxonomic composition were found, while the results of G procedure were significantly different when compared with both other procedures. Values of commonly used biotic and diversity indices calculated on the basis of those procedures were compared using correlation. The level of identification achieved sufficed for the proper determination of water quality classes at all of the sites sampled. [ABSTRACT FROM AUTHOR]

This paper records the microscopic acoel flatworm Wulguru cuspidata from the Northern Territory, in fact from the northern coastline of Australia, for the first time. Whilst being restricted to a narrow belt in the intertidal zone on sandy beaches fronting the ocean, this acoel can attain remarkably high densities. Despite the stressors it must experience in this habitat - of great fluctuations of temperature and salinity, and of toxic algal and bacterial blooms - it is present year round. Its behaviour, which is typical of acoels of the family Convolutidae, of moving to the surface of the substrate at low tide apparently to recharge its 'solar batteries' (i.e. provide light for its symbiotic microalgae) and of burying into the substrate at high tide, is described. Whilst this behaviour appears to be a response to a combination of tidal and daylight cycles, the biological clock causing it must be very complicated. [ABSTRACT FROM AUTHOR]

Using empirical analyses of the effects of global climate change (GCC) and ocean acidification (OA) on the survival and calcification of early life stages of Pocillopora damicornis, we employed a demographic approach to forecast the consequences of GCC and OA on the population dynamics of this coral. We constructed a size-based demographic model using life-history tables and transition probabilities for a population in Southern Taiwan, and projected the population structure over ~100 yr under scenarios of warming and acidification. The simulations incorporated stochastic variability of the parameters (±5 %), decline in larval survival due to increases in temperature and pCO, modified growth rates due to rising temperature, and larval input from distant populations. In a closed population, an increase of pCO from 40.5 to 91.2 Pa reduces density, and an increase in temperature from 26 to 29 °C results in population extirpation within 100 yr. With a larval supply of 10 % from distant populations, the population persisted regardless of high temperature (+3 °C). These results indicate that: (1) populations of P. damicornis may be resistant to GCC and OA so long as it persists as part of a metapopulation capable of supplying larvae from spatially separated populations and (2) early life stages can regulate the population dynamics of P. damicornis. [ABSTRACT FROM AUTHOR]

The present study aimed to explicitly quantify the link between the attributes of shallow-water gorgonian colonies (Octocorallia: Alcyonacea) and the ecological patterns of associated non-colonial epifaunal invertebrates. Based on multiple regression analysis, we tested the contribution of several attributes (colony height, width, and area, fractal dimension as a measure of colony complexity, lacunarity as a measure of the heterogeneity, and 'colonial' epibiont cover) to abundance and taxonomic richness of associated assemblages. The results highlight the variation in the response of epifaunal assemblages to the gorgonian colony characteristics. The nature and intensity of the relationships were gorgonian species-dependent and varied from one taxonomic group to another. For both gorgonian species analyzed, the strongest predictor of species richness and abundance of the epifaunal assemblages was 'colonial' epibiont cover, possibly due to a trophic effect (direct or indirect enhancement of food availability) combined with the surface available for colonization (species-area effect). Although structural complexity is usually indicated as the main driver for rich and abundant coral-associated assemblages, no significant relationship was observed between fractal dimension and the community descriptors; lacunarity, which reflects the sizes of the inter-branch spaces, was only linked to taxonomic richness in the assemblages associated with Leptogorgia lusitanica. The validity of the paradigm that structural complexity enhances biodiversity may be scale-dependent. In the case of gorgonians, the effect of complexity at the 'garden' level may be more relevant than at the individual colony level. This reinforces the need for the conservation of gorgonian aggregation areas as a whole in order to preserve host diversity and size structure. [ABSTRACT FROM AUTHOR]

ABSTRACT Invertebrates are among the most diverse organisms on Earth, significantly contribute to ecosystem function and integrity, and possess high potential as bioindicators. By definition, invertebrates also are wildlife. Yet, inclusion of invertebrates in peer-reviewed wildlife journals has not been investigated. As such, our objective was to assess inclusion of invertebrates in prominent wildlife journals published in the last decade. Based on our review and first-hand experience, we also aimed to provide recommendations for integration of invertebrates into wildlife science, education, and peer-reviewed literature. We performed a systematic literature review by manually searching all issues and articles from 2003-2013 of the following journals: European Journal of Wildlife Research, Journal of Wildlife Management, South African Journal of Wildlife Research, Wildlife Biology, Wildlife Research, and Wildlife Society Bulletin. We analyzed data derived from our review to elucidate trends in the inclusion of invertebrates in these journals. We identified 4,916 articles that involved animal taxa, of which 122 (2.5%) included invertebrates and <1% included invertebrates as focal taxa. Our results indicated invertebrates are included in a minute portion of articles in top wildlife journals. We recommend a paradigm shift to a less taxonomically homogenized and vertebrate-centric approach to wildlife science and education, integrating invertebrates into wildlife studies, and publishing results of those studies in wildlife journals to facilitate effective management of all wildlife species. © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Sixteen tardigrade species have been identified from a total of 943 specimens isolated from 69 positive soil samples collected in southern Spain (Andalusia, Huelva). Three genera (Hexapodibius,Xerobiotusand the new genusSarascon) and eight species are new records for the Iberian Peninsula, increasing Iberian tardigrade biodiversity by 6%, and 10 species are new records for soil habitats, increasing soil tardigrade biodiversity by 9% (from 96 to 108 species). A newly discovered species and genus are described, followed by an analysis and discussion of the species' phylogenetic position and synapomorphies, based on morphological and total evidence (morphology and molecular – 18S and 28S rRNA – data combined) phylogenetic analyses. The new genus is distinguished from other Itaquasconinae genera, to which it is phylogenetically related, by having aParasconbuccopharyngeal apparatus andRamajendasclaws. In contrast to general eutardigrade evolution, which is primarily determined by claw morphology, itaquasconid evolution is more related to buccopharyngeal apparatus morphology, which shows homoplastic evolution at superfamily, family and subfamily levels, and also defines functional trophic groups in soil-related environments. http://zoobank.org/urn:lsid:zoobank.org:pub:068B9D87-27E2-4B26-8920-FF03CEF9869A [ABSTRACT FROM AUTHOR]

Abiotic variability is known to structure lotic invertebrate communities, yet its influence on lentic invertebrates is not clear. This study tests the hypothesis that variability of nutrients and macro-ions are structuring invertebrate communities in agricultural drainage ditches. This was determined by investigating invertebrate adaptations to disturbance using insect life-history strategies. Many low-lying agricultural areas contain drainage ditches which potentially provide suitable habitat for aquatic invertebrates. In the province of North Holland (The Netherlands) the extensive network of eutrophic ditches are hydrologically managed, creating seasonal variability of water quality arising from agricultural run-off and the inlet of mineral rich, river derived water. This temporal variability was analysed from monitoring data, collected over a 7 month period (February till August) and covering 84 ditches in three soil regions; sand, clay and peat. Invertebrate diversity was determined as local ( α diversity), regional ( γ diversity) and species-turnover ( β diversity). We ran canonical correspondence analysis and linear mixed models to determine correlations between invertebrate diversity, functional community composition and specific abiotic parameters, including variability (expressed as the Median Absolute Deviation). Invertebrate α diversity was positively correlated to variability in water transparency and negatively correlated to average pH, with the two parameters reflecting a water quality gradient in the environment. Insect life-history strategies expressed adaptations to abiotic variability and harsh (eutrophic) conditions. These adaptations were mainly achieved through good dispersal abilities and developmental trade-offs. The results support measures to reduce influxes of excess nutrients to this network of ditches. [ABSTRACT FROM AUTHOR]

Summary data on oribatid mites of the genusAllonothrus(Trhypochthoniidae) of the Ethiopian region are presented. A new subspecies,Allonothrus schuilingi seychellinov. subsp., is described from Seychelles. It is distinguished on the basis of the shape and length of the notogastral and ventral setae. An identification key to all known African species ofAllonothrusis provided. http://zoobank.org/urn:lsid:zoobank.org:pub:0C1ED97C-BE49-4BB5-8E2B-E3F0F97C1663 [ABSTRACT FROM PUBLISHER]

The impact of heavy metals on macrobenthic invertebrates in five stations along the River Nile at Great Cairo (from Helwan to El-Qanater El-Khiria) was studied during the period from May, 2013 to February, 2014. Physico-chemical characteristics and heavy metals (iron, manganese, zinc, copper and cadmium) were analyzed in water. The highest average number (2305 org./m²) of macrobenthic invertebrates was recorded during spring, while the lowest (642 org./m²) was recorded during summer. Annelida, Mollusca and Arthropoda were the most dominant groups being 62 %, 34 % and 4 % respectively. Twenty two species and taxa were recorded; Mollusca (13 species) and Annelida (7 species) Arthropoda (2 species). All the heavy metal concentrations were within the permissible limits except at Helwan and Hawamdia due to the effect of discharged industrial wastes. The highest positive correlation was recorded between Arthropoda and iron & zinc, while iron recorded a negative correlation with Mollusca and Annelida. The principal component analysis (PCA) showed that the most dominant annelid Limnodrilus spp. had a positive correlation with cadmium and negative correlation with all other heavy metals. This indicates that this species can resist the high concentrations of cadmium. [ABSTRACT FROM AUTHOR]

Caves are long-known examples of evolutionary replications where similar morphologies (troglomorphies) evolve independently as the result of strong natural selection of the extreme environment. Recently, this paradigm has been challenged based on observations that troglomorphies are inconsistent across taxa and different subterranean habitats. We investigated the degree of replicated phenotypic change in two independent cave invasions by the freshwater isopod Asellus aquaticus; the first in a sulphidic aquifer in Romania, the second in a sinking river in the Dinaric Karst in Slovenia. Both ancestral surface populations still live alongside the subterranean ones. Phylogenetic analyses show independence of the two colonization events, and microsatellite analysis shows no evidence of ongoing genetic exchange between surface and subterranean ecomorphs. The overall morphology has changed dramatically at both sites (50 of 62 morphometric traits). The amount of phenotypic change did not reflect differences in genetic diversity between the two ancestral populations. Multivariate analyses revealed divergent evolution in caves, not parallel or convergent as predicted by the current paradigm. Still, 18 traits changed in a parallel fashion, including eye and pigment loss and antennal elongation. These changes might be a consequence of darkness as the only common ecological feature, because Romanian caves are chemoautotrophic and rich in food, whereas Slovenian caves are not. Overall, these results show that morphologically alike surface populations can diverge after invading different subterranean habitats, and that only about one-third of all changing traits behave as troglomorphies in the traditional sense. [ABSTRACT FROM AUTHOR]

A modeling approach that was used to predict the toxicity of dissolved single and multiple metals to trout is extended to stream benthic macroinvertebrates, freshwater zooplankton, and Daphnia magna. The approach predicts the accumulation of toxicants (H, Al, Cd, Cu, Ni, Pb, and Zn) in organisms using 3 equilibrium accumulation models that define interactions between dissolved cations and biological receptors (biotic ligands). These models differ in the structure of the receptors and include a 2-site biotic ligand model, a bidentate biotic ligand or 2-pKa model, and a humic acid model. The predicted accumulation of toxicants is weighted using toxicant-specific coefficients and incorporated into a toxicity function called Tox, which is then related to observed mortality or invertebrate community richness using a logistic equation. All accumulation models provide reasonable fits to metal concentrations in tissue samples of stream invertebrates. Despite the good fits, distinct differences in the magnitude of toxicant accumulation and biotic ligand speciation exist among the models for a given solution composition. However, predicted biological responses are similar among the models because there are interdependencies among model parameters in the accumulation-Tox models. To illustrate potential applications of the approaches, the 3 accumulation-Tox models for natural stream invertebrates are used in Monte Carlo simulations to predict the probability of adverse impacts in catchments of differing geology in central Colorado (USA); to link geology, water chemistry, and biological response; and to demonstrate how this approach can be used to screen for potential risks associated with resource development. Environ Toxicol Chem 2015;34:761-776. © 2015 SETAC [ABSTRACT FROM AUTHOR]

The serpulid tubeworm, Hydroides elegans , is an ecologically and economically important species whose biology has been fairly well studied, especially in the context of larval development and settlement on man-made objects (biofouling). Nevertheless, ontogenetic changes associated with calcareous tube composition and structures have not yet been studied. Here, the ultrastructure and composition of the calcareous tubes built by H. elegans was examined in the three early calcifying juvenile stages and in the adult using XRD, FTIR, ICP-OES, SEM and Raman spectroscopy. Ontogenetic shifts in carbonate mineralogy were observed, for example, juvenile tubes contained more amorphous calcium carbonate and were predominantly aragonitic whereas adult tubes were bimineralic with considerably more calcite. The mineral composition gradually shifted during the tube development as shown by a decrease in Sr/Ca and an increase of Mg/Ca ratios with the tubeworm’s age. The inner tube layer contained calcite, whereas the outer layer contained aragonite. Similarly, the tube complexity in terms of ultrastructure was associated with development. The sequential appearance of unoriented ultrastructures followed by oriented ultrastructures may reflect the evolutionary history of serpulid tube biominerals. As aragonitic structures are more susceptible to dissolution under ocean acidification (OA) conditions but are more difficult to be removed by anti-fouling treatments, the early developmental stages of the tubeworms may be vulnerable to OA but act as the important target for biofouling control. [ABSTRACT FROM AUTHOR]

The composition of benthic macroinvertebrate communities is influenced by a variety of factors, including the introduction of invasive species. However, only few analyses of factors influencing benthic community structure exist, especially those including invasive species. Our aim was to examine the importance of biotic factors on spatial and temporal variations in the benthic community within one system (Lake Constance, Germany). We examined the dependence of benthic community structure on invasive species by non-metric multidimensional scaling and distance-based redundancy analysis based on Bray-Curtis similarities. The three significant biotic factors explained 40% of the community variability. The mayfly Centroptilum luteolum and the snail Potamopyrgus antipodarum were positively associated with the amount of Chara, whereas some caddisfly taxa and Chironomidae were positively associated with the density of Dreissena polymorpha, which is a pattern most likely caused by their different habitat preferences. Several benthic taxa especially indigenous gammarids and Asellus aquaticus tended to decline with increased densities of the invasive amphipod Dikerogammarus villosus. Furthermore, density of D. villosus explained 26% of the benthic variability, demonstrating the strong impact of this species. Overall, our study demonstrates the large impact of invasive species on the composition of benthic macroinvertebrates. [ABSTRACT FROM AUTHOR]

Two new species of the genus Conothele Thorell 1878 of the trapdoor spider family Ctenizidae are described from India: Conothele giganticus, sp. nov. is described from the Ngengpui Wildlife Sanctuary, Mizoram in northeast India and C. khunthokhanbi sp. nov. is described from Manipur in northeast India. Like other known Indian Conothele species, these spiders are also strictly ground burrowing. Additional information on habitat and natural history is provided for both species. [ABSTRACT FROM AUTHOR]

The ability of non-native species to establish and spread is an interplay between the characteristics of the recipient ecosystem (e.g., biotic resistance) and the characteristics of the invading species (e.g., if it is a habitat generalist, fast-growing, highly fecund). In the Hawaiian Islands, the successful establishment and high impacts of many non-native species have been attributed to a disjunct flora and fauna that results in resources that can be readily exploited. Along these lines, the speed with which the Caribbean-Atlantic barnacle Chthamalus proteus became widespread in Hawaii has been attributed to the availability of settlement space in the intertidal zone. I investigated the relative importance of competition and recruitment in regulating the abundance of C. proteus at three sites on the island of Oahu. Recruitment of C. proteus and other barnacle species mirrored adult abundance. Competition with adult barnacles did not appear to be a factor at two sites. At a third site, where recruitment was the highest, competition between C. proteus and an early invader, Amphibalanus reticulatus , in the form of space pre-emption was occurring, apparently mediated at least in part by the preference of A. reticulatus to settle near conspecifics. C. proteus and the native barnacle Nesochthamalus intertextus displayed no such settlement preference. Earlier studies linked differences in recruitment rates of barnacles and other invertebrate species on Oahu to differences in circulation patterns that bring offshore waters into shore at some sites and hold near-shore water flowing out of lagoons and harbors close to shore in others. The present study adds to a growing body of work that suggests that while the relative importance of pre-settlement vs. post-settlement factors to invasion success varies with location, knowledge of local oceanographic conditions could help predict the spread of non-native marine species. [ABSTRACT FROM AUTHOR]

Despite the large number of studies on glaciers, knowledge regarding biota in cryoconite holes is limited. Cryophilic animals are often neglected in ecological studies on glacial habitats, but are important for the functioning of these environments. Owing to climate change and the melting of polar ice, cryophilic fauna could be threatened in the near future. We provide the first comprehensive survey of invertebrates inhabiting the cryoconite holes of Alpine, Antarctic, Arctic, Himalayan and Patagonian glaciers. At present, the list of taxa is rather short and includes five phyla ( Rotifera, Annelida, Tardigrada, Nematoda and Arthropoda). Owing to generally poor knowledge of the fauna of cryoconite holes, there could be more than the 25 currently known species. In addition, we present the geographical distributions of the taxa and discuss the diversity of invertebrates living in cryoconite holes and make predictions regarding the faunal diversity of these habitats. [ABSTRACT FROM AUTHOR]

This study examines the morphological features, suspended sediment inputs and hydraulic conditions within a large river in association with ecological patterns before and after a tributary confluence. In order to examine these effects, the macroinvertebrate distributions from three reaches of the Paraguay and Bermejo Rivers (Paraguay-Argentina) are investigated. The Bermejo River is a tributary that supplies significant quantities of fine sediment to the Paraguay River, primarily in suspension. Two reaches were examined on the Paraguay River, upstream and downstream of the Bermejo River junction, with the third study reach located on the Bermejo River, upstream of the confluence with the Paraguay River. The results provide clear evidence that a significantly increased loading of fine sediment at a river confluence has effects on the distribution and potential movement of benthic invertebrates in the lotic environment by representing physical barriers at affected sites. These effects may be important at both local and regional scales, and such increases in suspended sediment (especially associated with anthropogenic change) may thus pose a major threat to ecosystem integrity that has been historically underestimated. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Using macroinvertebrates as ecological indicators for different stressors has a long tradition. However, when applied to field data, one often observes correlations between different macroinvertebrate indices that can be attributed to both correlations of stressors and inherent correlations due to the sensitivity of taxa to different stressors. Ignoring the source of any given correlation leads to ambiguous conclusions about the impact of different stressors. Here, we demonstrate how to distinguish the causes of correlation by means of Monte Carlo simulations. We assessed to which degree trait-based indices are stressor-specific and whether this depends on the pool of taxa and its taxonomic resolution. Therefore, we (1) analysed the frequencies of “sensitive” and “insensitive” taxa for pairwise combinations of different indices, (2) analysed the inherent correlation of indices with random samples from different taxon pools derived from field samples and from a complete species list of a whole ecoregion, and (3) compared this inherent correlation with the actual correlation of the field samples. We exemplified this approach by analysing two existing indices (SPEAR pesticides , Saprobic Index) and new indices for temperature, flow and pH stress. We used these new indices to illustrate our approach while in-depth testing of their applicability was not the focus of our study. We found strong correlations between several indices in our study area at the Swiss Plateau. The probability that this correlation is only due to inherent correlation in the taxa sensitivities was low (maximum of 0.34). The problem of inherent correlation between indices is more severe for the smaller taxon pool with lower taxonomic resolution. Correlation in the sensitivity of different taxa to different stressors leads to an inherent correlation in trait-based indices, which weakens their explanatory power. Our results highlight the importance of correlation analyses when using trait-based indices to guide ecosystem-management, especially in regions with reduced biodiversity. [ABSTRACT FROM AUTHOR]

The Ogba River in southern Nigeria is an important water resource for its riparian communities. This study evaluates impact of anthropogenic influences on the Ogba River using water chemistry and macroinvertebrate data sets obtained over a period of 6 months between January and June 2012. Four stations, stations 1-4, characterised by various human activities were chosen along the river. Organic wastes from domestic and industrial sources were the major point sources of pollutants. Station 2 where the municipal wastewater drains into the river had elevated values of flow velocity, BOD, sulphate, phosphate, nitrate and sodium. Based on the canonical correspondence analysis (CCA), 5-day biochemical oxygen demand (BOD), sulphate, nitrate and phosphate were the main factors that help to shape the macroinvertebrate assemblage structure of the Ogba River. Macroinvertebrates clustered strongly by stations than by seasons indicating that water quality differences between the stations were responsible for the observed differences in the biotic assemblage. The preponderance of naidid oligochaetes, baetid nymphs and certain tolerant dipteran taxa including chironomids and ceratopogonids at all four stations was an indication that the entire water body was stressed. The odonates were the single most abundant taxa; their dominance could be attributed to the vegetative nature of the stream, favouring odonate colonisation. Overall, the responses of macroinvertebrates to stress were reflected by the different assemblage structures recorded at the four study stations. Substrate and microhabitat obliteration and poor water quality appeared to be the factors responsible for the observed assemblage structure in the Ogba River. [ABSTRACT FROM AUTHOR]

Fungi are diverse organisms that occupy important niches in natural settings and agricultural settings, acting as decomposers, mutualists, and parasites and pathogens. Interactions between fungi and other organisms, specifically invertebrates, are understudied. Their numbers are also severely underestimated. Invertebrates exist in many of the same spaces as fungi and are known to engage in fungal feeding or mycophagy. This review aims to provide a comprehensive, global view of mycophagy in invertebrates to bring attention to areas that need more research, by prospecting the existing literature. Separate searches on the Web of Science were performed using the terms "mycophagy" and "fungivore". Invertebrate species and corresponding fungal species were extracted from the articles retrieved, whether the research was field- or laboratory-based, and the location of the observation if field-based. Articles were excluded if they did not list at least a genus identification for both the fungi and invertebrates. The search yielded 209 papers covering seven fungal phyla and 19 invertebrate orders. Ascomycota and Basidiomycota are the most represented fungal phyla whereas Coleoptera and Diptera make up most of the invertebrate observations. Most field-based observations originated from North America and Europe. Research on invertebrate mycophagy is lacking in some important fungal phyla, invertebrate orders, and geographic regions.

Mysids are an important component of Great Lakes foodwebs, both as a prey for fish and as a predator on zooplankton. We monitored mysid abundance in Lake Ontario using lake-wide hydroacoustics data and vertical net hauls collected 1–5 August 2008 during the Ontario Ministry of Natural Resources and New York State Department of Conservation forage fish survey. Acoustic volume backscattering strength was highly correlated with both density and biomass of mysids although the correlation with biomass was stronger. The slopes of these relationships were not significantly different from theory (0.10) indicating a linear relationship between abundance and backscattering strength. Size structure significantly affected the relationship between backscattering strength and density but not between backscattering strength and biomass. Average target strength for areas with small mysids was −91.9 dB per mysid, and in areas with both small and large mysids it was −88.2 dB per animal. Acoustic estimates for Lake Ontario calculated with these regressions provided a lake-wide estimate weighted by lake area within depth intervals, of 228 mysids m−2(CV 17.6%) and 0.93 g dw m−2(CV 12.9%). Density and biomass in 14 net hauls averaged 316 mysids m−2(range 0 to 1113) and 1.35 g dw m−2(range 0 to 3.89). Mysid biomass was 33% of the biomass of other crustacean zooplankton in the summer of 2008. As in 2005, areas of low mysid abundance were detected in the middle of the transects and along the north shore. Lakewide mysid abundance in the summer of 2008 was higher than in a similar acoustic survey in the summer of 2005 and in whole-lake autumn 2000–2007 net surveys, suggesting that mysids are persisting in Lake Ontario and abundant relative to other Great Lakes. [ABSTRACT FROM AUTHOR]

Biodiversity loss is occurring rapidly worldwide, yet it is uncertain whether few or many species are required to sustain ecosystem functioning in the face of environmental change. The importance of biodiversity might be enhanced when multiple ecosystem processes (termed multifunctionality) and environmental contexts are considered, yet no studies have quantified this explicitly to date. We measured five key processes and their combined multifunctionality at three temperatures (5, 10 and 15 °C) in freshwater aquaria containing different animal assemblages (1-4 benthic macroinvertebrate species). For single processes, biodiversity effects were weak and were best predicted by additive-based models, i.e. polyculture performances represented the sum of their monoculture parts. There were, however, significant effects of biodiversity on multifunctionality at the low and the high (but not the intermediate) temperature. Variation in the contribution of species to processes across temperatures meant that greater biodiversity was required to sustain multifunctionality across different temperatures than was the case for single processes. This suggests that previous studies might have underestimated the importance of biodiversity in sustaining ecosystem functioning in a changing environment. [ABSTRACT FROM AUTHOR]

The paper presents a synthesis of systematical, ecological and biocenological researches on the macroarthropods, especially the entomofauna, realised in the last decades of the 20th Century, completed with recent observations realized in the Southern Transylvanian Tableland. The study area is situated on a Southern exposed hill slope of the Şerbuța Valley near the Şura Mare Commune, Sibiu County, with edaphic conditioned islands of stepic biocoenoses. The classes of macroarthropodes, especially Insecta with their orders, and in detail the Coleoptera with their families are analyzed in strong relation with their distribution in different habitats, disposed along ecological gradients on the Southern exposed hill profile. The remarkable biodiversity of the slope profile is highlighted. [ABSTRACT FROM AUTHOR]

The area of the Vltavský Luh (lower part of the Teplá Vltava stream and the Studená Vltava stream catchments) has been seriously altered by amelioration of mires and wet meadows and channelisation of streams draining them. Removal of the old drainages and restoration of the channelised sections of streams has been implemented to recover the hydrological regime of the area. Lower sections of the three streams, Hučina, Jedlový Potok and Žlebský Potok, have been restored in 2013-2015. The associated research is focused on the monitoring and evaluation of the success of these restorations. Main objectives are (i) to describe the colonisation of the restored stream channels by aquatic macroinvertebrates and the development of their assemblages in relation to flow and substratum conditions, (ii) to compare macroinvertebrate and plant communities before and after restoration, and (iii) to analyse the dynamics of vegetation changes in relation to the water regime and plant growth forms. [ABSTRACT FROM AUTHOR]

We monitored the invertebrate community of leaf litter in and around a drying intermittent pool bed to explore patterns of ecological organisation across a complex environmental gradient, with particular focus on population and community size structure. We measured the body size of 24,609 individuals from 313 taxa ranging over 6 orders of magnitude in size to explore how the functional properties of individuals, populations and communities are affected by moisture (aquatic vs. terrestrial) and light (diurnal vs. nocturnal), and how these properties change across the aquatic-terrestrial habitat transition that occurs as the pool bed dried. We found strong effects of moisture on some population (size structure) and many community (species richness, abundance, evenness, biomass and size structure) properties, with additional temporal effects across the aquatic-terrestrial ecotone. There was no difference between diurnal and nocturnal populations or communities. Our results facilitate understanding of how the physical environment influences functional attributes, and particularly the size structure, of natural populations and communities. [ABSTRACT FROM AUTHOR]

Various factors, such as habitat availability, competition for space, predation, temperature, nutrient supplies, presence of waterfalls, flow variability and water quality, control the abundance, distribution and productivity of stream-dwelling organisms. Each of these factors can influence the response of the density of organisms to a specific environmental gradient, inflating variability and making difficult to understand the possible causal relationship. In our study, we used quantile regression mixed models and Akaike's information criterion as an indicator of goodness to examine two different datasets, one belonging to Italy and one belonging to Finland, and to detect the limiting action of selected environmental variables. In the Italian dataset, we studied the relationships among five macroinvertebrate families and three physical habitat characteristics (water velocity, depth and substratum size); in the Finnish dataset the relationships between taxa richness and 16 environmental characteristics (chemical and physical). We found limiting relationships in both datasets and validated all of them on different datasets. These relationships are quantitative and can be used to predict the range of macroinvertebrate densities or taxa richness as a function of environmental characteristics. They can be a tool for management purposes, providing the basis for habitat-based models and for the development of ecological indices. [ABSTRACT FROM AUTHOR]

The octocoral Stragulum bicolor exhibits fast growth and frequently overgrows other invertebrates. This species has probably been introduced on the Brazilian coast. This study aims to evaluate the ability of S. bicolor to colonise previously occupied substrates and its influence on the fouling community throughout the successional process and to verify whether the community limits its growth. Experimental plates (15 × 15 cm) subjected to various treatments (cumulative control, cumulative with removal of S. bicolor , cumulative with removal of other species and non-cumulative) were submerged at 1-m depth for a period of 26 months in Paranaguá Bay in southern Brazil. The cumulative plates were photographed monthly, and the non-cumulative plates were recovered every two months and replaced with new ones. Species richness, diversity and evenness were compared between the control and experimental treatment without S. bicolor . The number of colonies, area and growth of S. bicolor were compared between the control and treatment without other species. Recruitment was compared among non-cumulative and without S. bicolor treatments. The effects of S. bicolor on species richness, diversity and evenness were sporadic. The community did not limit the area and growth of S. bicolor , and the number of colonies was higher on the control plates. Although the number of recruits was higher on non-cumulative plates in certain periods, the presence of an already developed community did not prevent recruitment. S. bicolor had no adverse effect on community development. However, this species was efficient in occupying both pre-colonised and clean substrates. It is important to monitor the population of S. bicolor in Paranaguá Bay because this species has probably been introduced in this region and has the potential to become invasive. [ABSTRACT FROM AUTHOR]

Here, we set target values to measure the ecological improvement of streams, based on invertebrate communities, riparian vegetation, instream habitat conditions and water chemistry. The study area is a large tropical catchment (Rio das Velhas, Minas Gerais, Brazil) affected by pastures, mining areas and a large urbanized area but also includes natural protected areas. Two stream types were found in the catchment, based on stream size, elevation, climate and geology with significantly different macroinvertebrate communities. In spite of a marked wet/dry seasons' climatic pattern, that does not result in the segregation of communities. Four classes of global degradation (IV-bad to I-good condition) were defined based on the available abiotic information, corresponding to a gradient in structure and biotic metrics of macroinvertebrate communities, matching the current knowledge on taxa sensitivity to pollution and general disturbance. Class I corresponds to target conditions to be achieved under restoration programmes. Using this approach, we were able to detect an improvement of abiotic conditions in four urban streams that benefited from enhancement measures in 2007-2008. However, invertebrate communities improved clearly in only one site (biotic metrics and community structure). Our study highlighted that good water quality alone is not enough and that only the combined effect of water quality, riparian vegetation and instream habitat condition enhancement resulted in the improvement of invertebrate communities. An important limiting factor for macroinvertebrate communities' recovery may be the distance to source populations. We concluded that the combined use of biological and abiotic target values for measuring the recovery of streams is needed to fully achieve an ecological restoration. This approach can also be valuable in the regular monitoring of streams to assess stream degradation. Target values based on other biological elements, such as fishes and algae, and functional processes could also contribute to define more global and realistic goals. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Two transects were established and sampled along altitudinal gradients on the slopes of Ariekammen (77°01′N; 15°31′E) and Rotjesfjellet (77°00′N; 15°22′E) in Hornsund, Spitsbergen. In total 59 moss, lichen, liverwort and mixed moss–lichen samples were collected and 33 tardigrade species of Hetero- and Eutardigrada were found. The α diversity ranged from 1 to 8 per sample; the estimated number of species based on all analysed samples was 52±17 for the Chao 2 estimator and 41 for the incidence-based coverage estimator. According to the results of detrended canonical correspondence analysis, altitude and type of substratum were the most important factors influencing tardigrade communities in the investigated area. Macrobiotus crenulatus, M. hufelandi hufelandi and Hypsibius pallidus dominated in the lower elevations, whereas Echiniscus wendti and E. merokensis merokensis prevailed in samples from higher plots. Macrobiotus islandicus islandicus was collected most often from mosses collected from rock whereas Isohypsibius coulsoni from mosses collected from soil. Analyses of covariance were employed to test for differences in species richness between the transects in relation to altitude. Contrary to expectations, there were significant differences in species richness between the transects, but richness was not significantly related to altitude. Interestingly, significant effects of colonies of seabirds, little auk (Alle alle), on the tardigrades communities were detected. Additionally, in one of the samples first ever males of Milnesium asiaticum were found. Their measurements and microphotographs are provided herein. [ABSTRACT FROM AUTHOR]

Reliance of profundal benthic macroinvertebrate assemblages on epilimnetic algal production - a key element of pelagic-benthic coupling - is a well-recognized phenomenon in the literature but the details are still poorly understood. In particular, the importance of taxonomic composition of algal communities and associated qualitative aspects of the settling material to benthic invertebrates is poorly known. We addressed this issue by investigating concordance of summer phytoplankton and profundal macroinvertebrate community composition using data from 47 boreal lakes. We examined community variation and environmental correlates of phytoplankton and macroinvertebrates with nonmetric multidimensional scaling ordinations. We also used cluster analysis to group sites according to their macroinvertebrate assemblages and evaluated the differences in phytoplankton composition and class-specific relative abundance among the clusters. Community concordance was evaluated with Procrustes rotation and partial Mantel tests, using oxygen concentration and phytoplankton biomass - the main drivers of macroinvertebrate community structure - as controlling factors. Procrustes and Mantel tests suggested congruence between macroinvertebrate and summer phytoplankton community composition. The concordance remained significant even after controlling for oxygen and biomass, by partial Mantel tests, suggesting a unique effect of phytoplankton species composition on macroinvertebrate assemblages. The four groups of lakes clustered by their macroinvertebrate assemblages also differed significantly in their phytoplankton taxa composition, and there were among-cluster differences in relative abundance of the seven most abundant phytoplankton classes. Our findings of community concordance of phytoplankton and profundal macroinvertebrates suggest a functional dependency of these two components, but further studies are needed to verify the actual causal mechanisms. [ABSTRACT FROM AUTHOR]

We examined the potential effects of environmental variables, and their interaction, on phytoplankton community succession in spring using long-term data from 1992 to 2012 in Lake Taihu, China. Laboratory experiments were additionally performed to test the sensitivity of the phytoplankton community to nutrient concentrations and temperature. A phytoplankton community structure analysis from 1992 to 2012 showed that Cryptomonas (Cryptophyta) was the dominant genus in spring during the early 1990s. Dominance then shifted to Ulothrix (Chlorophyta) in 1996 and 1997. However, Cryptomonas again dominated in 1999, 2000, and 2002, with Ulothrix regaining dominance from 2003 to 2006. The bloom-forming cyanobacterial genus Microcystis dominated in 1995, 2001 and 2007–2012. The results of ordinations indicated that the nutrient concentration (as indicated by the trophic state index) was the most important factor affecting phytoplankton community succession during the past two decades. In the laboratory experiments, shifts in dominance among phytoplankton taxa occurred in all nutrient addition treatments. Results of both long term monitoring and experiment indicated that nutrients exert a stronger control than water temperature on phytoplankton communities during spring. Interactive effect of nutrients and water temperature was the next principal factor. Overall, phytoplankton community composition was mediated by nutrients concentrations, but this effect was strongly enhanced by elevated water temperatures. [ABSTRACT FROM AUTHOR]

Sea cucumbers are dominant invertebrates in several ecosystems such as coral reefs, seagrass meadows and mangroves. As bioturbators, they have an important ecological role in making available calcium carbonate and nutrients to the rest of the community. However, due to their commercial value, they face overexploitation in the natural environment. On top of that, occurring ocean acidification could impact these organisms, considered sensitive as echinoderms are osmoconformers, high-magnesium calcite producers and have a low metabolism. As a first investigation of the impact of ocean acidification on sea cucumbers, we tested the impact of short-term (6 to 12 days) exposure to ocean acidification (seawater pH 7.7 and 7.4) on two sea cucumbers collected in SW Madagascar, Holothuria scabra, a high commercial value species living in the seagrass meadows, and H. parva, inhabiting the mangroves. The former lives in a habitat with moderate fluctuations of seawater chemistry (driven by day-night differences) while the second lives in a highly variable intertidal environment. In both species, pH of the coelomic fluid was significantly negatively affected by reduced seawater pH, with a pronounced extracellular acidosis in individuals maintained at pH 7.7 and 7.4. This acidosis was due to an increased dissolved inorganic carbon content and pCO of the coelomic fluid, indicating a limited diffusion of the CO towards the external medium. However, respiration and ammonium excretion rates were not affected. No evidence of accumulation of bicarbonate was observed to buffer the coelomic fluid pH. If this acidosis stays uncompensated for when facing long-term exposure, other processes could be affected in both species, eventually leading to impacts on their ecological role. [ABSTRACT FROM AUTHOR]