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Invertebrates are often used as indicators of ecosystem health. In community ecology, the use of organism traits (e.g. behavioural, biological or ecological) can be of value in relation to impact diagnosis and assemblage prediction. It has also been recognised that certain traits are related to ecosystem function, and their use in biological monitoring provide insights into ecosystem functional responses to stressors. However, the paucity of trait information and non-availability of a local trait database for southern African invertebrates impede progress in using this approach for biological monitoring. To address this critical gap, we compiled an updateable trait database for southern African freshwater invertebrates. The database contains information on 40 trait categories and 204 trait attribute/modalities. Of the 40 trait categories included in the database, 12 are biological, 12 are behavioural, and 16 are ecological preferences. The database is designed to accommodate taxonomic flexibility. In this regard, trait information is entered at multiple taxonomic levels: family, genus, and species, allowing researchers working at different taxonomic resolutions to retrieve relevant information. While there are still gaps in the database, this effort represents the first attempt to synthesise available trait information on southern African freshwater invertebrates. [ABSTRACT FROM AUTHOR]

The evolutionary history of the symbiotic association between arbuscular mycorrhizal fungi (AMF) and embryophytes dates back to the Devonian period. Previous ecological and physiological studies have described the presence of arbuscules, inter- and intracellular hyphae, vesicles, coils and spores, in liverworts and hornworts, which are considered absent in mosses. This study aimed to report the presence of AMF in a community of bryophytes (mosses and liverworts) from Punta Lara Natural Reserve, Argentina. Senescent and green sections of gametophytes were stained and, following microscopic observation, revealed AMF structures. We found intracellular hyphae, vesicles, spores and sporocarps associated with thallus and rhizoids of mosses and liverworts and senescent moss caulidia. The morphological characterization of spores resulted in the determination of Rhizophagus intraradices and Dominikia aurea. The species D. aurea is reported for the first time for Argentina. Sequencing of the D1 variable domain of the LSUrDNA from AMF spores mixes plus hyphae resulted in high similitude to the Dominikia sequences available from NCBI. This study reported the presence of AMF associated with declining and senescent gametophytes of bryophytes (mosses and liverworts) in a Natural Reserve in Argentina. These findings open up new lines of study, which should further investigate these associations and their diversity, physiology and significance. [ABSTRACT FROM AUTHOR]

We have studied the communities of soil-surface Coleoptera (Carabidae et Tenebrionidae) in the mountain hollows of Altai (Kurai and Chuya) and Tuva (Ulug-Khem and Ubsu-Nur; the arid western sector and the more humid eastern sector have been studied in the latter). Collections were made in the same habitats at intervals of about 60 years: in 1962–1963 and in 2018–2020. Climate change patterns over this period have been analyzed. In general, the climate of the characterized steppe hollows retains sharply continental features, with negative mean annual temperatures, moisture deficit, and a high frequency of fluctuations of all parameters. The average annual temperatures and the annual precipitation (during the last 10–20 years) have increased in all regions. These changes are most sharply pronounced in the Ulug-Khem hollow, creating the background for a reduction in aridity of environmental conditions. Over 60 years, the number of beetles of the studied taxa has changed several times, sometimes by more than an order of magnitude. At the same time, the number of representatives of the more xerophilic Tenebrionidae family decreased, while the number of the more mesophilic Carabidae increased. The proportions of tenebrionids in different habitats in 2018–2020 decreased significantly in comparison to the 1960s in almost all cases. More beetle species with a more northern or broader (polyzonal and/or trans-palaearctic) distribution are becoming more common in the Tuva hollows. Such species are found in both humid and arid regions. These changes in species compositions and soil-dwelling beetle communities may reflect mitigating climatic conditions due to some increase in precipitation in the studied region. The mean values of the indices of species diversity and evenness do not differ in general for the previous and current states of ecosystems. There are also no reliable differences for total species richness and total abundance. However, there are noticeable interannual differences for some diversity indices calculated for the Altai ecosystems in 2018 and 2020. This may indicate that differences between the overall diversity indices of ground beetle communities in dry and wet years overlap the long-term trend caused by climate change, and populations of species with different life strategies respond quickly to these changes without losing the overall structural complexity of the animal population. [ABSTRACT FROM AUTHOR]

• MAT was the main driver of bacterioplankton biodiversity in proglacial lakes. • 576 cold-preferred taxa and 2088 warm-preferred taxa were identified. • Cold-preferred taxa, play a crucial role in maintaining regional biodiversity. • Cold-preferred taxa are highly vulnerable, with narrow environmental niches. • Warm- preferred taxa have greater phenotypic flexibility. Recent climate warming and associated glacier retreat have dramatically changed the environmental conditions and microbial inhabitants of proglacial lakes. However, our understanding of the effects of climate warming and glacial influence on microbial biodiversity in these lakes remain relatively limited. Here, we studied bacterioplankton communities in 22 proglacial lakes on the Tibetan Plateau, spanning a range of nearly 7 °C in mean annual temperature (MAT), and examined the effects of climate and glaciers on their biodiversity by a space-to-time substitution. MAT emerged as the primary environmental driver of bacterioplankton biodiversity compared to glacial influence, increasing species richness and decreasing β-diversity. We identified 576 low-MAT (cold-preferred) species and 2,088 high-MAT (warm-preferred) species, and found that low-MAT species are less environmentally adapted, with their numbers declining as temperature increased. These results advance our understanding of temperature-driven bacterioplankton dynamics by disentangling the contrasting responses and adaptations of cold-preferred and warm-preferred species. Our findings highlight the vulnerability of cold-specialist taxa and the potential biodiversity losses associated with climate warming in the rapidly changing proglacial lakes. [Display omitted] [ABSTRACT FROM AUTHOR]

A new oribatid mite species of the genus Scutozetes (Oribatida) – S. arcticussp. nov. – is described from Vaygach Island, Yugor Peninsula, Taymyr Peninsula, and Ola Plateau, Magadan Region (Russia); it is morphologically most similar to Scutozetes lanceolatus in having slightly developed humeral notogastral process, but differs from the latter by the clavate bothridial seta, a flat lamellar plate (not covering lateral parts of prodorsum) having two pairs of anterolateral teeth on the anterior margin, well-visible rostral seta in dorsal view, and anterior margin of pedotectum I without tooth. An identification key to known recent species of the genus is given. The main morphological characteristics of Scutozetes are summarized. The geographical range of the new species is limited by arctic areas and subarctic mountain landscapes; most records are associated with dry and well-drained habitats. The identity of the genera Scutozetes and Lepidozetes is also discussed. [ABSTRACT FROM AUTHOR]

Determining whether epiphytic bryophytes have ecological preferences for woody plants remains difficult. Here, our primary aim in developing the torus-translation test is to evaluate the associations between epiphytic bryophytes and woody plants at the species, genus, or family levels in a 100 m × 100 m forest dynamics plot in a temperate, deciduous broad-leaved forest (China). We collected all the epiphytic bryophyte species on woody plants and recorded the woody plant species in the 1-ha plot in 2020. All the epiphytic bryophytes on the trees from the ground level up to 2 m were collected. We recorded 988 epiphytic bryophyte specimens belonging to 61 species in 254 woody plants. The Torus-translation test showed that 93.44% (57/61), 93.44% (57/61), and 98.36% (60/61) of the bryophyte species were significantly positively associated with the family, genus, and species of woody plants, respectively. A total of 317, 563, and 857 significant positive associations concerning the family, genus, and species of the woody plants were observed among the 61 examined bryophyte species. In addition, few significant negative associations were identified regarding the family, genus, and species of woody plants. More rare bryophyte species were positively correlated with woody plants than dominant bryophyte species. Our study demonstrates that most epiphytic bryophytes exhibit ecological habitat preferences for woody plants. These observations highlight the importance of the species composition of woody plants with respect to the maintenance of epiphytic bryophytes’ diversity. Epiphytic bryophytes’ growth preference for woody plants, especially rare bryophyte species, should be considered in the process of bryophyte diversity conservation in temperate, deciduous broad-leaved forests.

Questions: Land use legacies in current forest understorey vegetation, thoroughly studied in temperate regions, were investigated in a Mediterranean context. We tested the effect of three historical variables on current forest plant communities and traits: forest temporal continuity (ancient: forested before 1860, recent: reforested after 1860, and very recent forest: reforested after 1958) and type of land use in 1860 and 1958 (forest, pasture or arable land). Location: The Regional Natural Park of Luberon (southeastern France). Methods: We used a comprehensive vegetation plot database (473 species in 1,429 plots). Species' response to historical variables was tested with logistic regressions, and the relationship between plant traits and historical variables was analysed with RLQ and fourth‐corner analyses. Results: Among all studied species, 250 responded to forest temporal continuity, 208 to 1860 land use, and 246 to 1958 land use. Species associated with ancient forests were more frequently forest specialists or forest edge species, shade‐tolerant and perennials, while species associated with recent and very recent forests were more frequently annuals, anemochorous and heliophilous species. Species exhibited different traits and ecological preferences according to the type of land use prior to forest: therophytes were more frequent on former arable land while chamaephytes were more frequent on former pasture. Trait responses to 1860 and 1958 land uses were globally consistent. Conclusions: The effect of forest temporal continuity and past land use on forest understorey communities was consistent with other studies in northern Europe or northern America, which suggests that the same ecological processes apply in temperate lowland and Mediterranean regions. This study highlights a succession of plant communities in the long term and different trajectories of succession according to the type of former agricultural use. The long‐term legacies of past land use in current forest plant communities highlight the importance to preserve ancient forests, where typical forest species can be maintained. [ABSTRACT FROM AUTHOR]

Comammox Nitrospira , nitrifiers capable of performing complete nitrification on their own, are widely distributed in terrestrial ecosystems. However, their environmental preferences and factors that predict their biogeographic distribution have not been elucidated. Because most nitrifiers share the same basic life strategies and requirements, the best predictor of large-scale comammox bacterial abundance may be the abundance of other nitrifying guilds. To validate this hypothesis, we assembled data from 60 studies conducted in cropland, grassland, and forest ecosystems to identify abiotic and biotic parameters with the potential to predict comammox bacterial abundance and compare their predictive powers using random forest modelling. As expected, ammonia-oxidizing archaea (AOA) and bacteria (AOB) are the top two factors predicting comammox bacterial abundance, followed by soil pH and nitrate and ammonium (NH 4 +). Consistent evidence is present from cropland, grassland, and forest landscapes to show that comammox Nitrospira co-vary positively with AOA. On large spatial scales, soil pH and NH 4 + are the dominant influence on the abundance of clades A and B, respectively. A negative correlation with rainfall and acidity implies that clade A prefers dry, non-acidic environments, whereas a negative correlation with NH 4 + and rainfall indicates that clade B prefers dry, oligotrophic environments. These findings reveal that predictors at the aggregate and clade scales do not overlap, and the predictors of any single genetic clade may not be predictive of total abundance. Comammox Nitrospira prefer to co-metabolize with AOA with the same ecological preferences, hence the strongly positive population co-variation. However, the predictive power of incomplete nitrifiers as predictors may decline when modelling the abundance of a single genetic clade. At the clade level, comammox bacterial abundance is highly modulated by abiotic factors such as pH and NH 4 +. Niche differentiation between clade A and clade B is influenced more by pH and N status than by water status. [Display omitted] • Comammox Nitrospira clades A and B co-vary negatively with rainfall. • Comammox bacteria co-vary positively with AOA. • Biotic predictors have a stronger predictive power than abiotic predictors. • Comammox Nitrospira Clade A prefers dry, non-acidic environments. • Comammox Nitrospira Clade B prefers dry, oligotrophic environments. [ABSTRACT FROM AUTHOR]

This study investigated the major environmental factors structuring, for a year, phytoplankton assemblages in the Sfax saltern (Tunisia): salinity and nutrients. A STATICO analysis based on 11 environmental variables and the abundances of 64 phytoplanktonic species was conducted. STATICO is used to analyze the stable part of the relationships between the environment and species, and then to determine how these relationships change over time. The analysis confirmed that the salinity gradient had a considerable influence on the composition of the phytoplanktonic communities. Bacillariophyceae and Dinophyceae dominated in the least salty ponds, whereas Chlorophyceae and Cyanophyceae dominated in the saltiest ponds, in accordance with the halotolerance level estimated for each species by calculating the optimum salinity and salt tolerance. Nitrogen (N) and phosphorus (P) ions could have a secondary influence on the phytoplankton distribution and its dynamics. Dinophyceae seem to be favored by high ammonium (NH) concentrations, whereas diatoms seem to be favored by high orthophosphates (PO) and nitrates (NO) values. The Chlorophyceae Dunalliela salina thrived in the saltiest ponds when the NO concentrations increased. [ABSTRACT FROM AUTHOR]

The response of benthic invertebrate assemblages to stream restoration is the subject of numerous recent studies, but the process of recolonisation of restored river sections is still poorly understood. Field studies are often flawed by uncertainties about whether the observed species colonised the restored sections after restoration or whether they were present before restoration., We investigated restored streams in the Boye catchment in an urbanised area in Germany. The streams were formerly open sewers and thus were not inhabitable by benthic invertebrates, except for Oligochaeta. Restoration included the construction of underground sewers for wastewater and morphological remodelling of the stream bed., In the spring of 2012, we sampled seven restored former channels connected with near-natural upstream sections, which were never used as sewage channels and are in good status morphologically, and six unconnected restored former channels. Restoration measures had been conducted between one and 19 years before sampling. Additionally, we sampled 21 near-natural sites within the catchment and eleven near-natural sites in neighbouring catchments. Near-natural sites were considered to be potential source sites from which benthic invertebrates might colonise the restored sites., We recorded 128 taxa and categorised them into five dispersal classes that reflect dispersal capabilities and degree of ecological specialisation. Assemblages at restored sites were characterised by lower numbers of taxa and/or high abundance of hololimnic taxa and poorly dispersing winged species and by higher species numbers and abundance of strongly dispersing generalists., A distinct recolonisation sequence was derived from the observed patterns, in which winged, strongly dispersing generalists colonised most rapidly and were followed by hololimnic species, weakly dispersing generalists and habitat specialists. Restored sites connected with near-natural upstream sections were colonised more rapidly than unconnected restored sites, particularly by habitat specialists. Almost 90% of the recolonisation events originated from sources within a distance of 5 km. We observed a succession from pioneer assemblages to more mature communities, which resembles that of the surrounding near-natural sites., In conclusion, assemblages in connected, restored sites needed nine to 19 years to reach maturation, while the settlement of assemblages in unconnected sites is expected to require more time. [ABSTRACT FROM AUTHOR]

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Abstract: Based on published data and review of Mecynoptera splendida Handlirsch, 1904, a wing venation ground plan applicable to most taxa of the Palaeozoic superorder Palaeodictyopteroidea is proposed, where each major vein system has a simple anterior sector, and, primitively, a dichotomously branched posterior sector. Lodetiella magnifica nov. gen. and sp. is described, based on an isolated hind wing from the Salagou Formation (Middle to Late Permian; Hérault, France). The venation of Lodetiella magnifica conforms to the predicted ground plan, but differs by its simple posterior cubitus sector. This character is diagnostic of the family Calvertiellidae (Palaeodictyoptera), whose diagnosis is updated. Wing movement in flight is inferred from the peculiar wing vein organization of Lodetiella magnifica. Some ecological preferences might explain the relative rarity of calvertiellids in the fossil record. [Copyright &y& Elsevier]