Neurotoxin with probable ion channel impairing activity. Is both paralytic and lethal, when injected into lepidopteran larvae. Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. LD(50) is 0.20 mg/kg by subcutaneous injection. Belongs to the neurotoxin 21 family.