A method of controlling acarine pests comprises applying to the locus of
the acarine pests, an isolated polypeptide toxin, wherein the polypeptide
toxin has acaricidal activity. In one embodiment, the polypeptide toxin
comprises three intrachain disulfide bonds and/or is a component of a
venom of an Australian funnel web spider of the genus Atrax or
Hadronyche. The polypeptide toxins may be applied to the acarine pests
themselves, to the environment of the acarine pests, to the hosts of the
acarine pests, or to an animal vector of the acarine pests, for example.