It is hot and cold here: the role of thermotolerance in the ability of spiders to colonize tree plantations in the southern Atlantic Forest.

Worldwide, with the decline of natural habitats, species with reduced niche breadth (specialists) are at greater risk of extinction as they cannot colonise or persist in disturbed habitat types. However, the role of thermal tolerance as a critical trait in understanding changes in species diversity in disturbed habitats, e.g., due to forest replacement by tree plantations, is still understudied. To examine the role of thermal tolerance on the responses of specialist and generalist species to habitat disturbances, we measured and compared local temperature throughout the year and thermotolerance traits [upper (CTmax) and lower (CTmin) thermal limits] of the most abundant species of spiders from different guilds inhabiting pine tree plantations and native Atlantic Forests in South America. Following the thermal adaptation hypothesis, we predicted that generalist species would show a wider thermal tolerance range (i.e., lower CTmin and higher CTmax) than forest specialist species. As expected, generalist species showed significantly higher CTmax and lower CTmin values than specialist species with wider thermal tolerance ranges than forest specialist species. These differences are more marked in orb weavers than in aerial hunter spiders. Our study supports the specialisation disturbance and thermal hypotheses. It highlights that habitat-specialist species are more vulnerable to environmental changes associated with vegetation structure and microclimatic conditions. Moreover, thermal tolerance is a key response trait to explain the Atlantic Forest spider's ability (or inability) to colonise and persist in human-productive land uses.

The World Spider Trait database: a centralized global open repository for curated data on spider traits.

Spiders are a highly diversified group of arthropods and play an important role in terrestrial ecosystems as ubiquitous predators, which makes them a suitable group to test a variety of eco-evolutionary hypotheses. For this purpose, knowledge of a diverse range of species traits is required. Until now, data on spider traits have been scattered across thousands of publications produced for over two centuries and written in diverse languages. To facilitate access to such data, we developed an online database for archiving and accessing spider traits at a global scale. The database has been designed to accommodate a great variety of traits (e.g. ecological, behavioural and morphological) measured at individual, species or higher taxonomic levels. Records are accompanied by extensive metadata (e.g. location and method). The database is curated by an expert team, regularly updated and open to any user. A future goal of the growing database is to include all published and unpublished data on spider traits provided by experts worldwide and to facilitate broad cross-taxon assays in functional ecology and comparative biology. Database URL:https://spidertraits.sci.muni.cz/.

Spiders (Arachnida: Araneae) in the semideciduous Atlantic Forest: An ecological and morphological trait dataset for functional studies.

BACKGROUND: The semideciduous Atlantic Forest is one of the most diverse ecosystems in the world with a great diversity of spiders. Most spider-related studies in this ecosystem focused on species richness and composition; however, little is known about their trait diversity (including morphological, ecological and/or physiological traits). Two main datasets were compiled to generate a complete record of spider traits for this ecosystem. NEW INFORMATION: Here, we present two datasets about 259 species of spiders from the semideciduous Atlantic Forest of Argentina. The trait data set compiled information of morphological and ecological traits such as body size, femur length, ocular distance, foraging strategy, prey range, circadian activity and stratum preference; traits were assessed by species considering sexual dimorphism. The second dataset included information about phenology (season when spiders were collected), number of individuals assessed by species and presence/absence of spiders in the different sample sites. This dataset has high potential to help researchers in recording the state of a component of biodiversity (functional) and contributes with the study of ecosystem services and species conservation.