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...

High diversity and population structure in a widespread tarantula Sickius longibulbi (Mygalomorphae: Theraphosidae)

 


High diversity and population structure in a widespread tarantula Sickius longibulbi (Mygalomorphae: Theraphosidae)

ABSTRACT

Sickius Soares & Camargo, 1948 is a monotypic genus (Sickius longibulbi) characterized by a broad geographic distribution across Brazil and conservative morphology. Notably, females lack spermathecae, and males possess palpal bulb with a long embolus, both traits with taxonomic importance. The genus belongs to the infraorder Mygalomorphae, a group with intricate taxonomic challenges due to uniform morphology, complicating species delimitation. In the present study, we employed an integrative taxonomic approach, combining mitochondrial DNA sequences of the Cytochrome Oxidase I (COI) gene with Fourier Elliptical Analysis of the male palpal bulb shape to investigate lineage differentiation and evolutionary patterns within the genus Sickius. We observed genetic structured populations along with morphometric variation and geographic distribution, except for the two lineages localized in northeast Cerrado. We retain S. longibulbi as a single species with great diversity and possibly undergoing a process of divergence. Future studies with larger sample sizes are encouraged to confirm these findings and further investigate the evolutionary history of the genus.
Groppo, B. B., Morales, M. J., Belintani, T., & Guadanucci, J. P. L. (2025). High diversity and population structure in a widespread tarantula Sickius longibulbi (Mygalomorphae: Theraphosidae). Zoologischer Anzeiger. https://doi.org/10.1016/j.jcz.2025.08.007