Venomic adaptations of prey specialised spiders

Venom represents an important trait of countless animals, including many predators. Predatory venoms are usually very effective against certain prey as the result of evolutionary arms races. Nevertheless, many venomous animals remain understudied, including spiders, one of the most diversified groups of venomous predators. The vast majority of spiders are generalists who prey on a wide range of prey. However, a small proportion of spiders are prey-specialists that preferentially hunt only one prey type, often represented by dangerous prey, such as termites, ants or other spiders. They utilise morphological, behavioural and venomic adaptations to subdue such prey. Despite the current evidence suggesting that prey-specialised spiders immobilise prey with potent venom, their venoms haven’t been investigated in detail. In the research of our lab, we discovered that stenophagous prey-specialised spiders have smaller venom glands and less complex venoms compared to euryphagous generalists, as the venoms of specialists have presumably evolved to target only one prey type. Moreover, our laboratory bioassays revealed that the venoms of specialists are prey-specific. We also investigated the venom composition of one spider-eating specialist, the white-tailed spider (genus Lampona). The proteo-transcriptomic analysis identified more than 200 compounds in the Lampona venom. The main components were Cysteine-rich lampotoxins represented by peptides containing 8 to 10 Cysteine residues. Overall, we confirmed that prey-specialised spiders possess venomic adaptations allowing them to quickly subdue dangerous prey. Many aspects are still not explored, such as the venom composition and the mechanisms of prey-specificity of the majority of specialists, and I aim to investigate these features in my current research.