Joining the dark side: waterfall spiders in subterranean habitats, with the description of a new genus and two new species from Brazil (Araneae: Trechaleidae)

Posted by
  Joining the dark side: waterfall spiders in subterranean habitats, with the description of a new genus and two new species from Brazil (Araneae: Trechaleidae) Abstract Trechaleidae is a family of spiders often recognized by its semiaquatic species, but its diversity extends beyond these well-known examples. In this study, we describe Troglotrechalea gen. nov. , a new genus with two novel species, T. faleroae spec. nov. and T. agorai spec. nov. , found exclusively in subterranean habitats within karst formations in central and southeastern Brazil. Both species exhibit pale coloration, but unmodified eyes and legs if compared to other species in the family. The slight degree of troglomorphism, along with their geographic and habitat records, suggests that these species are restricted to hypogean habitats, although they probably move through epigean habitats. Additionally, we report in detail the occurrence of the trechaleid genera Enna O. Pickard-Cambridge, 1897, Heidrunea Brescovi...

Serine proteases and serine protease inhibitors identified from the venom gland transcriptome of Rhitymna verruca

Posted by

 


Serine proteases and serine protease inhibitors identified from the venom gland transcriptome of Rhitymna verruca

Abstract

Rhitymna verruca is a large nocturnal wandering spider and an important natural predator of agricultural and forestry pests, with its venom playing a key role in prey capture. However, systematic studies on the composition of its venom remain scarce. In this study, we performed an integrated analysis of the venom gland and venom samples using high-throughput transcriptome sequencing combined with quantitative proteomics. The transcriptome yielded 43,244 representative unigene sequences, among which 102 toxin-like sequences were identified through functional annotation, encompassing 13 peptide toxin superfamilies and 7 protein toxin families. Proteomic analysis identified 35 venom components, including 14 peptide toxins and 21 functional proteins. The most abundantly expressed toxin families, Superfamily IX and VII, were highly expressed at both transcriptomic and proteomic levels, suggesting central roles in prey paralysis and neuroregulation. Most peptide toxins possessed ICK or Kunitz domains, indicating high structural stability and potential target specificity. In addition, the venom was rich in auxiliary components such as CAP protein superfamily, hyaluronidases, and metalloproteases, which may contribute to toxin synergy, diffusion, and tissue disruption. This study provides the first comprehensive characterization of the venom composition of R. verruca, offering fundamental insights into its functional mechanisms, evolutionary patterns, and potential applications in the development of novel bioactive agents.
Li, Z., Zhang, M., Yin, W., Zheng, Y., Liu, H., Zhao, Y., & Yang, Z. (2026). Serine proteases and serine protease inhibitors identified from the venom gland transcriptome of Rhitymna verruca. Comparative Biochemistry and Physiology Part D: Genomics and Proteomics, 58, 101719. https://doi.org/10.1016/j.cbd.2025.101719