Insect and vertebrate active toxin. Binds at site 4 of mammalian voltage-gated sodium channels and shifts the activation voltage of the mammalian rNav1.2a (SCN2A) channel to more hyperpolarized voltages, whereas the insect channel, DmNav1 (para), is not affected. Causes temporary paralysis when injected into lepidopteran larvae at 8.6 nmol/g. A low intracranial injection dose into mice causes lacrimation, closure of the eyes and sweating. A high injection dose causes extensive lacrimation and death. Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. The primary structure of the mature toxin is identical to that of beta-hexatoxin-Mg1a (Magi-5) from Macrothele gigas (AC P83561). Belongs to the neurotoxin 15 family. 01 (magi-5) subfamily.