Venom Mass Fingerprints for Species Delimitation, Reloaded: A Test Case with Italian Scorpions (Euscorpius)

  Venom Mass Fingerprints for Species Delimitation, Reloaded: A Test Case with Italian Scorpions (Euscorpius) Abstract Scorpion venoms are complex mixtures of bioactive compounds including proteins, peptides and enzymes. Although venoms exhibit substantial intraspecific variation, some compounds appear to be species-specific, highlighting their potential as chemotaxonomic markers. Venom mass fingerprints (MFPs) derived from Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry (MS) have been proposed as a means of delimiting species. However, their utility for species delimitation has rarely been evaluated against independent sources of taxonomic evidence. In the present study, the performance of MALDI-TOF MS-based venom peptide barcoding (mass ranges of m/z 800‒4500 and m/z 3000‒10,000) was assessed in 52 populations of eight Italian species of the scorpion genus Euscorpius Thorell, 1876, representing different levels of evolutionary divergenc...

Simulating a hybridization event of a range-expanding sexual cannibal (Argiope bruennichi)

 


Simulating a hybridization event of a range-expanding sexual cannibal (Argiope bruennichi)

Abstract

Hybridization plays an important role in animal speciation. Mediterranean populations of the Palaearctic wasp spider Argiope bruennichi have recently undergone a range expansion northwards. Adaptation to colder winters was facilitated by introgressed alleles derived from Asian populations, hence the resulting hybrids were able to expand geographically. Argiope bruennichi exhibits a highly complex mating system that includes strong sexual conflict and predisposes the species to behaviours that could facilitate directed hybridization and hybrid stabilization. To test this, we simulated a hybridization event with European and Asian spiders and a backcrossing event with southern and northern European spiders by conducting mate choice experiments and mating trials. We found pronounced differences in the cannibalism and monopolization successes between the populations. Asian male spiders were more successful in monopolizing European females than their European conspecifics and more successful than European males with Asian females. This would have led to an increased proportion of these specific offspring in the hybrid population. Our results suggest the mating system as a driving factor in the directional hybridization of Asian males and European females and the establishment of new northern European populations of A. bruennichi. We found no influences of the mating system on the stabilization of the resulting hybrid populations, probably owing to cold survival adaptations being a more important factor.


Sebastian Franke, Jutta M Schneider, Simulating a hybridization event of a range-expanding sexual cannibal (Argiope bruennichi), Biological Journal of the Linnean Society, 2024;, blae018, https://doi.org/10.1093/biolinnean/blae018