Hidden in the wrack: spider (Arachnida, Araneae) diversity and new records for Italy from Posidonia banquettes

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  Hidden in the wrack: spider (Arachnida, Araneae) diversity and new records for Italy from Posidonia banquettes ABSTRACT Posidonia oceanica (L.) Delile beach wrack deposits (banquettes) are a characteristic coastal habitat of the Mediterranean Sea, yet their invertebrate communities remain poorly studied. Here we report the results of a survey from January to November 2024 of the spider fauna (Order Araneae) associated with Posidonia banquettes at Sant’Agostino beach (Civitavecchia, Latium, central Italy), using four complementary sampling methods (surface and underground pitfall traps, Berlese-Tullgren funnel extraction, and visual census). A total of 161 specimens were collected, with 17 species assigned to 11 families among adult individuals. The dominant families were Argyronetidae (39.4%), represented exclusively by Chaerea maritimus Simon, 1885, and Gnaphosidae (33.8%). Three species are recorded for the first time in Italy: Dysdera gamarrae Ferrández 1984, Gnaphosa jucu...

BEYOND SPECIES-LEVEL DIFFERENCES: A COMPREHENSIVE REVIEW OF INTRASPECIFIC VENOM PLASTICITY IN SPIDERS

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BEYOND SPECIES-LEVEL DIFFERENCES: A COMPREHENSIVE REVIEW OF INTRASPECIFIC VENOM PLASTICITY IN SPIDERS

Abstract

Spider venoms represent a diverse array of biological cocktails, crucial for predator-prey dynamics and ecological interactions. While differences in venom composition between species (interspecific variation) are well-characterized, the extent and drivers of intraspecific venom plasticity remain a critical, underexplored area. This comprehensive review synthesizes current research on venom variation within species, emphasizing the multifaceted factors that govern this dynamic phenotype. Venom composition, yield, and bioactivity are significantly influenced by both endogenous and exogenous elements. Endogenous factors, mainly sexual dimorphism and ontogenetic stage, often induce profound changes in potency, reflecting sex-specific ecological pressures, predation risk profiles, and shifting reproductive investments. Similarly, exogenous pressures, including seasonal and geographic variations, drive adaptive shifts in venom profiles in response to environmental gradients like temperature and prey availability. Furthermore, recent advances in proteomics and transcriptomics reveal substantial individual-level chemo-diversity, underscoring the complexity of underlying regulatory mechanisms. A paradigm shift is necessary, viewing venom not as a static species characteristic but as a highly plastic, environmentally and genetically mediated trait. Future research must prioritize high-resolution, long-term intra-individual and population-level studies, especially in globally underrepresented taxa and regions, to fully elucidate the ecological and evolutionary forces shaping this crucial biological system.
Anna Anannya, K., & Malamel, J. J. (2026). BEYOND SPECIES-LEVEL DIFFERENCES: A COMPREHENSIVE REVIEW OF INTRASPECIFIC VENOM PLASTICITY IN SPIDERS. Toxicon, 109121. https://doi.org/10.1016/j.toxicon.2026.109121