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...

Understanding the habitat selection and natural history of the spider Deinopis cf. cylindracea (Deinopidae)

 


Understanding the habitat selection and natural history of the spider Deinopis cf. cylindracea (Deinopidae)

Abstract

Habitat choice is fundamental for an animal foraging, defense, and reproduction. Ogre-faced spiders are known for their unusual morphology, natural history, and rarity. They are sit-and-wait predators that build net-like webs that are manipulated by spiders and thrown at their prey. Hunting behavior includes selecting microhabitats for web construction that reduces the likelihood of damage or entanglement in the substrate during prey capture. Therefore, we expect that Deinopis cf. cylindracea selects smooth surfaces to forage on. We observed D. cf. cylindracea associated with smooth trunks of Plinia cauliflora (Myrtaceae) in the natural environment and actively selecting smooth trunks over rough trunks or litter in controlled experiments. Such selection is likely to maximize the foraging strategy of launching the web towards the substrate. Aggregations had occurred more often in the 50 cm trunk closest to the ground, where the prey community is largest. During the day, this spider appears to choose sites where it can adopt a stick-like posture upon the vegetation near the ground. Hunting at night and resting cryptically during the day appears to be shaped by natural selection for the survival and reproduction of this spider species.

Villanueva-Bonilla, G. A., Stefani, V., Ponte, R. P. da ., & Vasconcellos-Neto, J.. (2024). Understanding the habitat selection and natural history of the spider Deinopis cf. cylindracea (Deinopidae). Brazilian Journal of Biology, 84, e284487. https://doi.org/10.1590/1519-6984.284487