Qualitative and Quantitative Proteomic Analysis of Venoms from Mexican Rattlesnakes

  Qualitative and Quantitative Proteomic Analysis of Venoms from Mexican Rattlesnakes Abstract Despite the vast biodiversity of Mexican vipers, venom of endemic species has been barely studied. Here we analyzed the venom composition of three endemic species of rattlesnakes: Crotalus aquilus , C. triseriatus , and C. ravus . We used quantitative chromato-mass-spectrometry and compared venoms with C. molossus , a species commonly found in North America, in a comparative and phylogenetic framework. In total, we identified 165 proteins grouped in 19 main protein families, consistent with previous reports for viperid venoms. In C. aquilus and C. triseriatus , the most predominant protein-family type was Serine Proteases, and in C. triseriatus and C. molossus it was Snake Venom Metalloproteases. The Label-free quantification revealed a high proportion of Snake Venom Metalloproteases in C. aquilus , C. triseriatus , and C. molossus , reaching 28–47% of the total venom. In contrast, in ...

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