Influence of grazing and solar panel installation on tenebrionid beetles (Coleoptera Tenebrionidae) of a central Asian steppe.

Grazing may represent a major threat to biodiversity in arid grasslands. The increasing use of grasslands for solar parks may represent a new important threat. No study has investigated the effects of solar parks on soil insects. Tenebrionids are a major component of the arthropod fauna of grasslands of central Asia. These ecosystems are threatened by grazing and increasing land use for solar parks. Aim of this work was to investigate the effects of grazing and solar panels on tenebrionids in arid grasslands (desert steppe) in China by comparing their community structure in ungrazed, heavily grazed, and solar park sites. Beetles were sampled by pitfall traps, and sites were compared for abundance and diversity (Hill numbers). All sites were characterized by simple, strongly dominated tenebrionid communities. Species proportions varied among sites. Grazing negatively influenced overall abundance, but did not alter species proportions; by contrast, solar panels had no effect on the average abundance, but reduced the proportion of the most abundant species. Compared with the other two sites, the solar park was characterized by a higher plant biomass and lower temperatures. A major availability of resources and less harsh conditions in the solar park might have a role in reducing the dominance of the most abundant species, allowing other species to attain higher abundances. This led to a more balanced community structure, with higher values of diversity. Although neither grazing nor solar panel installation modified radically tenebrionid species-abundance distribution or diversity, grazing and solar panel installation had different effects in species abundances and their impact might amplify the effect of other disturbance factors such as the ongoing climate change.

Global tropical reef fish richness could decline by around half if corals are lost.

Reef fishes are a treasured part of marine biodiversity, and also provide needed protein for many millions of people. Although most reef fishes might survive projected increases in ocean temperatures, corals are less tolerant. A few fish species strictly depend on corals for food and shelter, suggesting that coral extinctions could lead to some secondary fish extinctions. However, secondary extinctions could extend far beyond those few coral-dependent species. Furthermore, it is yet unknown how such fish declines might vary around the world. Current coral mass mortalities led us to ask how fish communities would respond to coral loss within and across oceans. We mapped 6964 coral-reef-fish species and 119 coral genera, and then regressed reef-fish species richness against coral generic richness at the 1° scale (after controlling for biogeographic factors that drive species diversification). Consistent with small-scale studies, statistical extrapolations suggested that local fish richness across the globe would be around half its current value in a hypothetical world without coral, leading to more areas with low or intermediate fish species richness and fewer fish diversity hotspots.

Use of microarthropods to evaluate the impact of fire on soil biological quality.

Edaphic (i.e. soil dwelling) microarthropods play crucial roles in soil ecosystem services. Fire is a widespread form of disturbance with severe effects on soil invertebrates. Research on the effects of fire on soil arthropods, however, has been mostly focused on surface-active species. Information on the effects of fire on strictly edaphic invertebrates is limited. Thanks to their variable degree of specialization to the edaphic life, soil microarthropods can be used to evaluate soil quality and how it is affected by disturbance. We used an index of soil biological quality based on microarthropods (QBS-ar) to assess the effects of wildfire in three habitats (a natural beechwood, a grassland and a conifer reforestation) in a burnt upland plain in Central Italy, one year after the fire event. Fire affected significantly soil biology quality. In all habitats, burnt soils had a biological quality about 1.4 lower than the respective unburnt soils. Sampling period did not affect QBS-ar values. QBS-ar values varied among habitat types, being highest in the beechwood, lowest in the pinewood, and intermediate in the grassland. These findings indicate that the QBS-ar approach can be profitably used to evaluate the impact of fire on soil biology quality and stress the poor performance of planted conifers in terms of soil quality.

Corals hosting symbiotic hydrozoans are less susceptible to predation and disease.

In spite of growing evidence that climate change may dramatically affect networks of interacting species, whether-and to what extent-ecological interactions can mediate species' responses to disturbances is an open question. Here we show how a largely overseen association such as that between hydrozoans and scleractinian corals could be possibly associated with a reduction in coral susceptibility to ever-increasing predator and disease outbreaks. We examined 2455 scleractinian colonies (from both Maldivian and the Saudi Arabian coral reefs) searching for non-random patterns in the occurrence of hydrozoans on corals showing signs of different health conditions (i.e. bleaching, algal overgrowth, corallivory and different coral diseases). We show that, after accounting for geographical, ecological and co-evolutionary factors, signs of disease and corallivory are significantly lower in coral colonies hosting hydrozoans than in hydrozoan-free ones. This finding has important implications for our understanding of the ecology of coral reefs, and for their conservation in the current scenario of global change, because it suggests that symbiotic hydrozoans may play an active role in protecting their scleractinian hosts from stresses induced by warming water temperatures.

The Watson-Forbes Biogeographical Controversy Untangled 170 Years Later.

Hewett Cottrell Watson and Edward Forbes were two naturalists of the Victorian age. They were protagonists on a dispute that generated comment and serves as an illuminating case study of misunderstanding in priority issues. Watson accused Forbes of having plagiarized his original classification of the British plants into groups on the basis of their geographical distribution. This controversy originated mostly from a so-far-ignored basic difference in Watson's and Forbes' ideas about biogeographical regionalization. Watson's classification of the British flora into groups of species with similar distribution was probably the first application of the concept of "regional chorotype." By contrast, the biogeographical classification of the British flora proposed by Forbes belongs to the concept of "element," because it was based on assumed species history (i.e. colonization routes). The two approaches may produce similar outcomes, but remain conceptually different. Although personal reasons may have contributed to exacerbate the Watson-Forbes controversy, failure in recognizing this distinction by its actors and their contemporaries, such as Hooker and Darwin, was the most important cause.

Are generalist parasites being lost from their hosts?

Co-extinctions should be regarded as fundamental co-evolutionary events promoting species turnover, prior than a consequence of human induced biodiversity loss. Focusing on current scenarios is key to biodiversity conservation, but predicting future trends could be harder and less fruitful than trying to get a better grasp on the past.

Response of macrophyte communities to flow regulation in mountain streams.

River macrophytes are widely used in freshwater ecosystem assessment because of their sensitivity to anthropogenic pressures, even if there are only a few studies that investigated how macrophytes respond to water regime alterations. In this study, we analyzed the effects of dams on river macrophyte communities through a comparison between upstream and downstream sides from 18 dams located in Alps and Apennines. A co-inertia analysis and a Mantel test were applied to assess if the analysis of environmental parameters could be effective in predicting macrophyte community structure. We analyzed morphological and physicochemical inter-site differences and tested the influence of dams on various aspects of community structure (composition, richness, diversity, dominance, coverage) using multivariate randomized block permutation procedure. Plant similarity between sites was evaluated at the level of phylum, and indicator species analysis was performed to identify the taxa most sensitive or tolerant to water regulation. We found that the overall environmental setting overwhelms the dam impact and that the influence of hydrological alteration became apparent when comparing upstream and downstream assemblages at the same dam. In particular, we found that most of taxa had a higher affinity with the downstream side and that in general, stream regulation increases plant richness and coverage, but reduces community evenness. Analyses based on higher taxonomic groups (phyla) demonstrated that this community can be effectively used in bioassessment even at phylum level analysis. In particular, we found that bryophytes, strictly linked with changes in substrate stability, show particular sensitivity to water regulation in mountain streams.

Relations between species rarity, vulnerability, and range contraction for a beetle group in a densely populated region in the Mediterranean biodiversity hotspot.

Rarity is often considered an indication of species extinction risk, and it is frequently used to obtain measures of species vulnerability. However, there is no strong evidence of a correlation between species vulnerability and threat. Moreover, there is no consensus about how rarity should be measured. I used a multidimensional characterization of species rarity to calculate a vulnerability index for tenebrionid beetles inhabiting an Italian region in the Mediterranean biodiversity hotspot. I used different metrics to examine 3 dimensions of rarity: species range, ecology, and population. Species with rarity values below the median were scored as rare for each dimension. I combined rarity scores into a vulnerability index. I then correlated species vulnerability with range trends (expanded vs. contracted). Different measures of the same rarity dimension were strongly correlated and produced similar vulnerability scores. This result indicates rarity-based vulnerability estimates are slightly affected by the way a certain rarity dimension is measured. Vulnerability was correlated with range trends; species with the highest vulnerability had the strongest range contraction. However, a large number of common species also underwent range contraction in the last 50 years, and there was no clear relation between range contraction and their ecology. This indicates that in general human-induced environmental changes affected species irrespective of their assumed vulnerability and that focusing only on rare species may severely bias perceptions of the extent of species decline.

Upward and Poleward (but Not Phenological) Shifts in a Forest Tenebrionid Beetle in Response to Global Change in a Mediterranean Area.

There is an increasing volume of literature on the impact of climate change on insects. However, there is an urgent need for more empirical research on underrepresented groups in key areas, including species for which the effects of climatic change may seem less evident. The present paper illustrates the results of a study on a common forest tenebrionid beetle, Accanthopus velikensis (Piller and Mitterpacher, 1783), at a regional scale within the Mediterranean basin. Using a large set of records from Latium (central Italy), changes in the median values of elevation, latitude, longitude, and phenology between two periods (1900-1980 vs. 1981-2022) were tested. Records of A. velikensis in the period 1981-2022 showed median values of elevation and latitude higher than those recorded in the first period. Thus, in response to rising temperatures, the species became more frequent at higher elevation and in northern places. By contrast, A. velikensis does not seem to have changed its activity pattern in response to increased temperatures, but this might be an artifact due to the inclusion of likely overwintering individuals. The results obtained for A. velikensis indicate that even thermally euryoecious species can show changes in their elevational and latitudinal distribution, and that poleward shifts can be apparent even within a small latitudinal gradient.

Macroecology of Dung Beetles in Italy.

The Italian fauna includes about 170 species/subspecies of dung beetles, being one of the richest in Europe. We used data on dung beetle distribution in the Italian regions to investigate some macroecological patterns. Specifically, we tested if species richness decreased southward (peninsula effect) or northward (latitudinal gradient). We also considered the effects of area (i.e., the species-area relationship), topographic complexity, and climate in explaining dung beetle richness. Finally, we used multivariate techniques to identify biotic relationships between regions. We found no support for the peninsula effect, whereas scarabaeines followed a latitudinal gradient, thus supporting a possible role of southern areas as Pleistocene refuges for this group of mainly thermophilic beetles. By contrast, aphodiines were more associated with cold and humid climates and do not show a distinct latitudinal pattern. In general, species richness was influenced by area, with the Sardinian fauna being however strongly impoverished because of its isolation. Faunal patterns for mainland regions reflect the influence of current ecological settings and historical factors (Pleistocene glaciations) in determining species distributions.

Ground spiders (Chelicerata, Araneae) of an urban green space: intensive sampling in a protected area of Rome (Italy) reveals a high diversity and new records to the Italian territory.

Background: Urbanisation is a rapidly growing global phenomenon leading to habitat destruction, fragmentation and degradation. However, urban areas can offer opportunities for conservation, particularly through the presence of green spaces which can even provide important habitats for imperilled species. Spiders, which play crucial roles in ecosystem functioning, include many species that can successfully exploit urban environments. Placed in the middle of the Mediterranean global biodiversity hotspot, Italy possesses an exceptionally rich spider fauna, yet comprehensive data on urban spider communities are still limited. More information on urban spiders in Italy would be extremely beneficial to support conservation efforts, especially in central and southern Italy, where knowledge on the spider fauna is largely incomplete. New information: The current study focused on the spider diversity of a large protected area (Appia Antica Regional Park) in urban Rome, Italy. A total of 120 spider species belonging to 83 genera and 28 families were identified, with 70 species being new records to the Province of Rome, 39 to the Latium Region and two (Pelecopsisdigitulus Bosmans & Abrous, 1992 and Palliduphantesarenicola (Denis, 1964)) to Italy.Forty-one species were recorded during autumn/winter sampling and 107 in spring/summer. The spider fauna recorded from the study area included about 37% of the total spider fauna known from the Province of Rome, 28% of that of the Latium Region and 7% of the entire Italian territory. The most represented families in terms of species richness were Gnaphosidae and Linyphiidae, which accounted for more than 40% of the sampled fauna. Lycosidae were the most abundant family (29% of captured individuals), followed by Zodariidae (16% of captured individuals), Linyphiidae (13% of captured individuals) and Gnaphosidae (7.5% of captured individuals). From a biogeographical point of view, most of the collected species belonged to chorotypes that extend for large areas across Europe and the Mediterranean. The research highlights the role of urban green spaces as refuges for spiders and the importance of arachnological research in urban areas as sources of information on spider biodiversity at larger scales.

Biogeographical Patterns of Earwigs in Italy.

Placed in the center of the Mediterranean biodiversity hotspot, Italy plays a central role for the study of Europe's biogeography. In this paper, the influence of climatic, spatial, and historical factors on current patterns of variation in earwig species richness and composition is investigated. The Italian earwig fauna is mainly composed of species which are either widely distributed in Europe and the Palearctic region or that are endemic to the Alps and the Apennines. Variation in species richness does not follow any obvious geographical patterns, but a positive influence of precipitation on richness is consistent with earwig preferences for humid climates. European mainland territories did not contribute substantially to the current biodiversity of Italian earwigs, which explains the lack of a distinct peninsula effect, although a southward decrease in similarity with the central European fauna was observed. However, southern areas did not exert a pivotal role during Pleistocene glaciations in determining current patterns of species richness. Variation in species composition among Italian regions can be mostly explained by geographical proximity, while climatic differences and historical (paleogeographical and paleoecological) events seem to have played a minor role. However, the isolation of ancient earwig stocks on Italian mountains led to the origin of a relatively large number of endemics, which makes the Italian earwig fauna one of the richest in Europe.

Ellenberg Indicator Values Disclose Complex Environmental Filtering Processes in Plant Communities along an Elevational Gradient.

Ellenberg indicator values (EIVs) express plant preferences for temperature, light, continentality, soil moisture, pH, and soil nutrients, and have been largely used to deduce environmental characteristics from plant communities. However, EIVs might also be used to investigate the importance of filtering mechanisms in shaping plant communities according to species ecological preferences, a so far overlooked use of EIVs. In this paper, we investigated how community-weighted means (CWM), calculated with EIVs, varied along an elevational gradient in a small mountain in Central Italy. We also tested if species abundances varied according to their ecological preferences. We found that the prevalence of thermophilous species declines with elevation, being progressively replaced by cold-adapted species. Heliophilous species prevail at low and high elevations (characterized by the presence of open habitats), whereas in the middle of the gradient (occupied by the beech forest), sciophilous species predominate. Variations for moisture and soil nutrient preferences followed a similar pattern, probably because of the high moisture and nutrient levels of forest soils with a lot of humus. No distinct pattern was detected for EIVs for pH and continentality since these factors are subject to more local variations. These results highlight the possible role of EIVs to investigate how environmental gradients shape plant communities.

Odonate Diversity Patterns in Italy Disclose Intricate Colonization Pathways.

As a natural bridge between Europe and Africa, Italy occupies a prominent position to understand the biogeography of Europe. The influence of climatic, spatial, and historical factors on current patterns of species richness and turnover (i.e., inter-regional biogeographical differences) has been analyzed for 88 species occurring in 17 Italian natural regions. Use of multimodel inference showed that odonate richness decreased southwards in response to decreasing rainfall, as expected for animals that depend on freshwater for their development. Use of Mantel tests indicated that patterns of inter-regional similarities were influenced by both climate and geographical distances. These patterns, as highlighted using Non-Metric Multidimensional Scaling, indicate a role for historical factors. Biogeographical similarities between Italian regions and adjacent areas revealed multiple colonization pathways. These results, coupled with the overall southward decrease in species richness, suggest that, after serving as a Pleistocene refuge from which odonates may have colonized medio-European areas, Italy was in turn subject to colonization from north to south. This resulted in Italian odonate fauna being less species rich compared to faunas in the medio-European territories, but also being biogeographically very complex.

Historical Biogeography of Earwigs.

The Dermaptera are an insect order exhibiting their highest diversity in the tropical areas of the southern hemisphere. This pattern has been considered a reflection of a Gondwanan origin. However, this hypothesis has not been tested through analytical methods. In this paper, the world distribution of earwigs was analysed by using the 'Cladistic Analysis of Distributions and Endemism' (CADE), a method which groups areas of endemism on the basis of shared distributions and phylogenetic relationships among taxa. In addition, clustering techniques were applied to depict biotic relationships based on similarity indices. Results of CADE support the idea that Gondwanan fragmentation exerted a crucial role in shaping the current distribution of the main clades of earwigs. However, the relationships between India with South East Asia suggested a biotic interchange occurred after the Indian collision with the Eurasian plate. The overall scenario emerging from cluster analyses revealed a strong influence of dispersal events. Overall, the distribution of earwig major clades indicates that their biogeographical history was mainly characterized by vicariance events (led by the break-up of Gondwana) followed by large scale dispersal processes constrained by the Himalayan orogenesis and the presence of colder temperatures, which have largely hampered the colonization of the northern hemisphere.

Use of Lichens to Evaluate the Impact of Post-Earthquake Reconstruction Activities on Air Quality: A Case Study from the City of L'Aquila.

Lichens are widely used as bioindicators of air quality because of their ability to absorb chemical pollutants. We used the Lichen Diversity Value (LDV) index to assess the effects of the urban reconstruction activities in the city of L'Aquila ten years after the 2009 earthquake on air quality. Sampling was conducted from the city centre (still mostly under reconstruction and closed to traffic) to suburban areas (where reconstruction is minimal). We tested if the LDV index varied with distance from the city centre because of the presence of air pollutants produced by reconstruction works. We also used Energy-Dispersive X-ray Spectroscopy (EDS) to detect the main pollutants accumulated in the sampled lichens. The LDV increased from the city centre towards suburban areas. EDS revealed high concentrations of pollutants related to demolition and reconstruction activities, such as aluminium and silicon (used in the manufacture of concrete), in the more central areas. These results suggest that the LDV index can be a useful tool to monitor air quality, even on a small scale, and in urban environments subject to building demolition and reconstruction. Moreover, EDS could represent a good preliminary analytical technique to identify the air pollutants associated with all of these activities.

Interactional behaviors of the parasitic beetle Paussus favieri with its ant host Pheidole pallidula: the mimetic role of the acoustical signals.

The social parasitic beetle Paussus favieri (Coleoptera, Carabidae, Paussini) performs different types of stridulations, which selectively mimic those emitted by different ant castes of its host Pheidole pallidula (Hymenoptera, Formicidae, Myrmicinae). However, the significance of this acoustical mimicry for the success of the parasitic strategy and the behaviors elicited in the host ants by stridulations was unknown. We reared Paussus favieri in Pheidole pallidula colonies and filmed their interacting behaviors. We analyzed in slow motion the behavior of ants near a stridulating beetle. We analyzed separately trains of pulse (Pa + Pb, produced by repeated rubbings) and single pulse (Pc, produced by a single rubbing) of stridulations, clearly recognizable from the shaking up and down of the beetle hind legs, and associated them with different ant responses. The full repertoire of sounds produced by P. favieri elicited benevolent responses both in workers and soldiers. We found that different signals elicit different (sometimes multiple) behaviors in ants, with different frequency in the two ant castes. However, Pc (alone or in conjunction with other types of pulses) appears to be the type of acoustic signal mostly responsible for all recorded behaviors. These results indicate that the acoustic channel plays a pivotal role in the host-parasite interaction. Finding that a parasite uses the acoustical channel so intensively, and in such a complicated way to trigger ant behaviors, indicates that acoustic signals may be more important in ant societies than commonly recognized.

Niche overlap and species co-occurrence patterns in carabid communities of the northern Chinese steppes.

Understanding how species sort themselves into communities is essential to explain the mechanisms that maintain biodiversity. Important insights into potential mechanisms of coexistence may be obtained from observation of non-random patterns in community assembly. The spatial niche overlap (Pianka index) and co-occurrence (c-score) patterns in carabid species in three types of steppes (desert steppe, typical steppe, and meadow steppe) in China was investigated. Non randomness was tested using null models. Niche overlap values were significantly higher than expected by chance in the desert steppe, where vegetation cover is less abundant and less uniformly distributed, which possibly forces species to concentrate in certain places. In the typical and meadow steppes, results were influenced by the scale of the analysis. At a broad scale, niche separation was found as a result of species segregation among different sectors (habitats) within these steppes, but when the analysis was conducted at a finer scale, species appeared to be no more segregated than expected by chance. The high co-occurrence averages found in the meadow and typical steppes indicate that the distributions of the species found in a site may be negatively affected by the presence of other species, which suggests that some species tend to exclude (or reduce the abundance of) others. The very low c-score average observed in the desert steppe suggests that competition is not involved there. Thus, in more homogeneous landscapes (such as the typical and meadow steppes), competition might play some role in community structure, whereas spatial variation in the abundances of species is more driven by the uneven spatial distribution of vegetation in the landscape where productivity is lower and less uniformly distributed.

Variations in Plant Richness, Biogeographical Composition, and Life Forms along an Elevational Gradient in a Mediterranean Mountain.

Despite the increasing interest in elevational patterns in biodiversity, few studies have investigated variations in life forms and biogeographical composition, especially in the Mediterranean biome. We investigated elevational patterns in species richness, biogeographical composition (chorotypes) and life forms (Raunkiaer classification) along an elevational gradient in a Mediterranean mountain (Central Italy). We found a general hump-shaped pattern of species richness, which can be explained by harsher conditions at the lowest and highest elevations. This pattern is distinctly related to prevalence at mid elevations of species with European and Euro-Asiatic distribution, which are favored by a temperate climate. Phanerophytes and geophytes (which are mainly associated with woods) were concentrated at mid elevations where woodlands prevail. Hemicryptophytes increased with elevation, consistently with their ability to cope with high altitude climatic conditions. Mediterranean species declined with elevation because they are negatively affected by decreasing temperatures. Chamaephytes showed a U-shaped pattern, suggesting they are able to cope with arid and cold conditions at the extremes of the gradient. Endemics increased with elevation because of their association with mountainous areas as key places for endemism evolution. These results illustrate how elevational patterns in species richness, biogeographical composition and life forms are interrelated and demonstrate reciprocal insights for understanding current vegetation settings.