Induces an immediate fast muscle contraction followed by flaccid paralysis when injected into blowfly larvae. The paralytic effect is lower in mice and fish. Has strong cytolytic activity against insect Sf9 cells and human HeLa cells, weak activity against human JAR cells, and no activity against human HEK293 cells. Binds to erythrocyte membranes and has weak hemolytic activity, probably mediated by oligomerization and pore formation. Forms a membrane channel in the prey. Found in whole body extract but not in the cnidocyst. PD(50) is 0.36 mg/kg by injection in blowfly larvae, in PubMed:12885226. PD(50) is 0.557 mg/kg by injection in blowfly larvae, in PubMed:15824108. Belongs to the hydralysin family.