The chromosome-level genome of Mesobuthus martensii provides insights into its evolution and the diversity of venom peptides

  The chromosome-level genome of Mesobuthus martensii provides insights into its evolution and the diversity of venom peptides Abstract Mesobuthus martensii , the source species of the traditional Chinese medicine “Quanxie”, has long been utilized for its therapeutic properties. Venom peptides are recognized as the major active molecular basis of these pharmacological activities. Despite this, their development as therapeutic agents remains poorly explored. In this study, we performed an integrated multi-omics investigation to systematically explore the venom peptides of Mesobuthus martensii . We generated a chromosome-level genome assembly of Mesobuthus martensii using third-generation sequencing technologies, yielding a genome size of 1.08 Gb with a contig N50 of 46.46 Mb. Integrated genomic and transcriptomic analyses led to the identification of 51 putative novel venom peptide candidates. From the broader venom peptide set, five lysine- and arginine-rich candidates were select...

Male burrow investment drives differential sperm transfer in a South American spider

 


Male burrow investment drives differential sperm transfer in a South American spider

Abstract

In species with male multiple matings, males may transfer sperm differentially according to several factors such as their reproductive status and body condition, and those of their sexual partners. Spiders provide exceptional models for studying sexual selection due to their unique reproductive system, sperm storage capabilities, and diverse mating strategies. However, the factors influencing male sperm transfer in this group remain underexplored. We examined the sperm transfer patterns in the Neotropical wolf spider Allocosa senex, males of which construct and donate burrows as reproductive and paternal investment. We investigated whether male and female traits such as age and body condition (i.e. the residuals of a linear regression between prosome width and weight), and male investment in burrow construction (burrow length) influence sperm transfer. Finally, we tested the relationship between sperm transfer, the number of ejaculations, and mating duration. Our results show that sperm transfer increased with burrow length, which serves both as an advertisement to attract mates and as paternal effort in this species, suggesting this trait probably serves as an honest signal of overall male quality. Interestingly, longer mating duration showed lower sperm transfer, indicating that mating serves multiple functions beyond sperm transfer, while the positive relation among sperm transfer and the number of ejaculations support using ejaculation count as a measure of sperm transfer in this species. These findings offer new insights into the diverse factors shaping ejaculate transfer in A. senex, contributing to the understanding of factors driving the evolution of reproductive strategies in spiders and other arthropods.


Bollatti, F., Aisenberg, A., & Peretti, A. V. (2026). Male burrow investment drives differential sperm transfer in a South American spider. Biological Journal of the Linnean Society, 147(1). https://doi.org/10.1093/biolinnean/blaf142