Water-seeking behavior among terrestrial arthropods and mollusks in a cool mesic region: Spatial and temporal patterns

Dehydration can have negative effects on animal physiological performance, growth, reproduction, and survival, and most animals seek to minimize these effects by reducing water losses or seeking water sources. Much—but not all—of the research on animal water balance comes from dryland ecosystems. However, animals inhabiting mesic regions may also experience desiccating conditions, for example within urban heat islands or during heatwaves and droughts. Here we examined how spatial variation in impervious surface and spatial and temporal variation in microclimate impact water demand behavior of terrestrial arthropods and mollusks in three areas of mesic Northwest Ohio, with analysis of taxa that exhibited the greatest water demand behavior. Water demand behavior was measured as the frequency that individuals were observed at an artificial water source (a moistened pouch), relative to the frequency at a control (a dry pouch). Overall, terrestrial arthropods and mollusks were found about twice as often at the water source than at the control (equivalent to 86 more observations on the wet pouch than on dry at each site, on average), with ants accounting for over 50% of the overall response in urban areas. Daily fluctuations in vapor pressure deficit (VPD) best predicted daily variation in water demand behavior, with increased demand at higher VPD. Mean VPD was generally highest near urbanized areas, but effects of VPD on water demand behavior were generally lower in urbanized areas (possibly related to reductions in overall abundance reducing the potential response). On certain days, VPD was high in natural areas and greenspaces, and this coincided with the highest arthropod water demand behavior observed. Our results suggest that terrestrial arthropod communities do experience periods of water demand within mesic regions, including in greenspaces outside cities, where they appear to respond strongly to short periods of dry conditions—an observation with potential relevance for understanding the effects of climate change.

A Fine-Scale Hotspot at the Edge: Epigean Arthropods from the Atacama Coast (Paposo-Taltal, Antofagasta Region, Chile)

The Atacama Desert at its margins harbors a unique biodiversity that is still very poorly known, especially in coastal fog oases spanning from Perú towards the Atacama coast. An outstanding species-rich fog oasis is the latitudinal fringe Paposo-Taltal, that is considered an iconic site of the Lomas formation. This contribution is the first to reveal the knowledge on arthropods of this emblematic coastal section. We used pitfall traps to study the taxonomic composition, richness, and abundance of terrestrial arthropods in 17 sample sites along a 100 km section of the coast between 24.5 and 25.5 southern latitude, in a variety of characteristic habitats. From a total of 9154 individuals, we were able to identify 173 arthropod species grouped into 118 genera and 57 families. The most diverse group were insects, with 146 species grouped in 97 genera and 43 families, while arachnids were represented by 27 species grouped into 21 genera and 14 families. Current conservation challenges on a global scale are driving the creation and evaluation of potential conservation sites in regions with few protected areas, such as the margins of the Atacama Desert. Better taxonomic, distributional, and population knowledge is urgently needed to perform concrete conservation actions in a biodiversity hotspot at a desert edge.

Two new scorpion species from protected areas in Antofagasta Region, Chile (Scorpiones, Bothriuridae, Brachistosternus)

We describe two new scorpion species of genus Brachistosternus from protected areas of Antofagasta Region in northern Chile. Brachistosternus chimba n. sp. has only been collected in La Chimba National Reserve, in the Chilean Coast Range. Brachistosternus llullaillaco n. sp. is a high altitude Andean species of the Lullaillaco National Park. Both species were collected as part of the first survey of the terrestrial arthropods of the protected areas of Antofagasta Region, in the frame of the First National Biodiversity Inventory of Chile of the Integrated System for Monitoring and Evaluation of Native Forest Ecosystems (SIMEF) and Project FIC-R Recovery Plan for La Chimba National Reserve.

Wolbachia prevalence in the vector species Culex pipiens and Culex torrentium in a Sindbis virus-endemic region of Sweden

Background Wolbachia pipientis are endosymbiotic bacteria present in a large proportion of terrestrial arthropods. The species is known to sometimes affect the ability of its host to transmit vector-borne pathogens. Central Sweden is endemic for Sindbis virus (SINV), where it is mainly transmitted by the vector species Culex pipiens and Culex torrentium, with the latter established as the main vector. In this study we investigated the Wolbachia prevalence in these two vector species in a region highly endemic for SINV. Methods Culex mosquitoes were collected using CDC light traps baited with carbon dioxide over 9 years at 50 collection sites across the River Dalälven floodplains in central Sweden. Mosquito genus was determined morphologically, while a molecular method was used for reliable species determination. The presence of Wolbachia was determined through PCR using general primers targeting the wsp gene and sequencing of selected samples. Results In total, 676 Cx. pipiens and 293 Cx. torrentium were tested for Wolbachia. The prevalence of Wolbachia in Cx. pipiens was 97% (95% CI 94.8–97.6%), while only 0.7% (95% CI 0.19–2.45%) in Cx. torrentium. The two Cx. torrentium mosquitoes that were infected with Wolbachia carried different types of the bacteria. Conclusions The main vector of SINV in the investigated endemic region, Cx. torrentium, was seldom infected with Wolbachia, while it was highly prevalent in the secondary vector, Cx. pipiens. The presence of Wolbachia could potentially have an impact on the vector competence of these two species. Furthermore, the detection of Wolbachia in Cx. torrentium could indicate horizontal transmission of the endosymbiont between arthropods of different species. Graphical abstract

Arthropod-Microbiota Integration: Its Importance for Ecosystem Conservation

Recent reports indicate that the health of our planet is getting worse and that genuine transformative changes are pressing. So far, efforts to ameliorate Earth’s ecosystem crises have been insufficient, as these often depart from current knowledge of the underlying ecological processes. Nowadays, biodiversity loss and the alterations in biogeochemical cycles are reaching thresholds that put the survival of our species at risk. Biological interactions are fundamental for achieving biological conservation and restoration of ecological processes, especially those that contribute to nutrient cycles. Microorganism are recognized as key players in ecological interactions and nutrient cycling, both free-living and in symbiotic associations with multicellular organisms. This latter assemblage work as a functional ecological unit called “holobiont.” Here, we review the emergent ecosystem properties derived from holobionts, with special emphasis on detritivorous terrestrial arthropods and their symbiotic microorganisms. We revisit their relevance in the cycling of recalcitrant organic compounds (e.g., lignin and cellulose). Finally, based on the interconnection between biodiversity and nutrient cycling, we propose that a multicellular organism and its associates constitute an Ecosystem Holobiont (EH). This EH is the functional unit characterized by carrying out key ecosystem processes. We emphasize that in order to meet the challenge to restore the health of our planet it is critical to reduce anthropic pressures that may threaten not only individual entities (known as “bionts”) but also the stability of the associations that give rise to EH and their ecological functions.

Investigating how neonicotinoids effect Abundance, Behaviour, Condition, Reproductive success and Survival for non-target terrestrial arthropods.

This meta-analysis aims to update and improve upon a previous attempt at understanding the effects neonicotinoids have on non-target terrestrial arthropods. While the original authors carried out sufficient analysis on the data they collected, there are new methodologies that can improve the accuracy of the final effect sizes produced. This new meta-analysis will use a multi-level approach, meaning that it will not consider data to be independent from the studies they were collected from. Instead the data and subsequent effect sizes will be nested within the studies, allowing for a truer effect size to be synthesised.

ASSESSING ANT DIVERSITY IN AGROECOSYSTEMS: THE CASE OFITALIAN VINEYARDS OF THE ADIGE VALLEY

Agroecosystems have gained a dominant positionon worldwide land-usage, and therefore preserving their biodiversity is crucial for environmental sustainability. Ants are one of the most widespread groups of terrestrial arthropods, and,thanks to their significant diversification,they are considered as a good proxy group for bio-diversity monitoring, also in agroecosystems. Vineyards are economically valuable cultures widespread worldwide,and hosting many ant species, that provide meaningful ecosystem services and disservices. Despite the important role that ants play in these agroecosystems, ant biodiversity in vineyards is still poorly studied, especially in Italy. In this context, we present a first detailed quantitative and qualitative assessment of the ant fauna of Italian vineyards from the Adige Valley based on pitfall traps data, and discuss the results in comparison with the few other similar assessments from Europe and other continents. We document anassemblage of 22 species (7-16 per or-chard), mostly dominated by three disturbance-tolerant species (including an introduced species). Vineyards’ ant faunas appear to be rather heterogeneous worldwide, mainly following local ecological and biogeographical constraints, and the role that most ant species play in these agroecosystems is presently unknown.