Venom of prey-specialised spiders is more toxic to their preferred prey: a result of prey-specific toxins

1. In specialised predators a variety of adaptations have evolved to such a level of specificity that they allow very effective exploitation of focal prey. Venom is an essential adaptive trait of predatory venomous species, such as spiders, yet our knowledge of spider venom is incomplete. 2. In agreement with the prey preference hypothesis, we expected that the venom of spider specialists should be more toxic to focal than to alternative prey, because it is composed of prey-specific toxins. 3. Here we used spiders with three types of trophic specialisations: specialists that were ant-eating, termite-eating, and spider-eating. We compared the efficacy of prey capture of preferred and alternative prey (measured as paralysis latency) with that of related generalists and profiled the venom of the studied species using proteomic methods. We used 22 spider species: six myrmecophagous, two termitophagous, three araneophagous, and 11 euryphagous generalist species belonging to different familie...