An unusually complex venom system in araneophagous palp-footed spiders (Palpimanidae)

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  An unusually complex venom system in araneophagous palp-footed spiders (Palpimanidae) Venoms are key adaptive traits in many animal lineages, yet their structural and functional diversity in spiders remains poorly investigated. Here, we present an initial characterization of the venom system of palp-footed spiders (Palpimanidae), a family specialized in hunting other spiders. Using micro-computed tomography, we found that the venom glands of the single species examined, Palpimanus gibbulus , exhibit a complex, multi-lobed morphology that is unusual among araneomorph spiders. Proteo-transcriptomic analyses of two Palpimanus venoms ( P. gibbulus and P. cyprius ) revealed highly diverse putative toxin repertoires comprising hundreds of peptides and proteins, including numerous novel putative neurotoxins, cytotoxins, enzymes, and allergens. Five major families of cysteine-rich palpitoxins were identified as the dominant putative neurotoxic components in both species, displaying con...

Elevational patterns and assembly processes of centipede and spider diversity on Changbai Mountain, China

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Elevational patterns and assembly processes of centipede and spider diversity on Changbai Mountain, China

Abstract

Mountain elevational gradients provide natural experiments for testing how biodiversity responds to strong and predictable climatic change, yet soil predatory invertebrates remain poorly studied. Here, we investigated centipede (Chilopoda) and spider (Araneae) assemblages along an elevational gradient on Changbai Mountain, northeast China, to evaluate how elevation structures taxonomic, functional and phylogenetic diversity. Across 64 plots spanning eight elevations (800–1850 m), we quantified taxonomic, functional and phylogenetic α- and β-diversity. Functional structure was characterized using four traits for centipedes and eight for spiders, species-level phylogenies were reconstructed from COI sequences, and β-diversity was partitioned into turnover and nestedness. We further used null-model standardization to test whether β-diversity deviated from stochastic expectations and assessed the effects of climate and litter chemistry. Taxonomic, functional and phylogenetic α-diversity all declined significantly with elevation in both taxa, with generally steeper declines in spiders. Community composition diverged strongly among elevations across all three facets, and β-diversity increased with elevational distance. Taxonomic β-diversity was turnover-dominated in both taxa, indicating that elevational differentiation mainly reflected species replacement. Functional β-diversity showed a stronger nestedness component, suggesting contraction of functional trait space toward higher elevations. Phylogenetic β-diversity differed between taxa: spiders were mainly turnover-dominated, whereas centipedes showed a stronger nestedness component. Standardized effect sizes revealed non-random structuring in taxonomic and phylogenetic β-diversity, whereas functional non-randomness was more evident in centipedes. Annual mean temperature, annual mean precipitation and litter pH were the most consistent predictors of both α- and β-diversity. However, litter element effects differed between taxa: centipede β-diversity was associated mainly with litter C, N and C/N, whereas spider β-diversity was more closely related to litter P, C/P and N/P. These results show that elevation filters species, ecological strategies and evolutionary lineages in forest floor predator communities in facet- and guild-dependent ways.
Wan, Z., Wu, Y., Zhang, P., Ma, H., Liu, M., Xie, Z., Wu, D., & Scheu, S. (2026). Elevational patterns and assembly processes of centipede and spider diversity on Changbai Mountain, China. Geoderma, 474, 118039. https://doi.org/10.1016/j.geoderma.2026.118039