Broad-Scale Climatic Gradients Drive Multiple Facets of Scorpion Beta Diversity in Northeastern Brazil

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  Broad-Scale Climatic Gradients Drive Multiple Facets of Scorpion Beta Diversity in Northeastern Brazil ABSTRACT Aim Beta diversity analyses clarify mechanisms structuring ecological communities, but their multidimensional facets remain poorly explored in arthropods. Here, we quantified taxonomic, phylogenetic, and functional beta diversity in scorpions, partitioned these facets into species replacement and richness differences, and evaluated the relative importance of spatial structure and environmental conditions in driving community assembly. Location Northeastern Brazil, South America. Taxon Scorpions (Arachnida: Scorpiones). Methods Taxonomic beta diversity was estimated using species presence across 70 sites in northeastern Brazil. Phylogenetic turnover was calculated from a multi-locus molecular tree, and functional beta diversity was derived from morphometric and ecological traits. All beta diversity facets were decomposed into replacement and richness-difference component...

Evidence of population stress linked to droughts in cave-dwelling spiders: the case of Meta bourneti in north-western Italy

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Evidence of population stress linked to droughts in cave-dwelling spiders: the case of Meta bourneti in north-western Italy

ABSTRACT

Subterranean spiders of the genus Meta are frequent inhabitants of the twilight zones of European caves, where they play a key ecological role as apical predators. We assessed the abundance variation and breeding success of M. bourneti populations after an extensive drought period that affected north-western Italy during 2022. Across three different caves, we compared data with the results of a previous monitoring study performed in 2012–2013 in the same sites, which are at the gedge of the species’ range in the Italian peninsula. From December 2022 to December 2023, we carried out three surveys in spring and winter seasons. We detected a total of 20 M. bourneti individuals, while more than 100 individuals were reported in 2012–2013. Moreover, we did not observe any cocoons. The observed decline and absence of breeding may reflect cyclic or stochastic population fluctuations, but it is worth noting that an extensive drought occurred during the period 2021–2022. We emphasize the importance of establishing long-term monitoring of M. bourneti populations in Mediterranean regions to improve our understanding of the potential effects of climate change in subterranean ecosystems.

Galbiati, M., Graziani, F., Manenti, R., Mammola, S., & Caimi, B. (2025). Evidence of population stress linked to droughts in cave-dwelling spiders: the case of Meta bourneti in north-western Italy. The European Zoological Journal, 92(1), 896–905. https://doi.org/10.1080/24750263.2025.2536018