Heterodimer: postsynaptic neurotoxin. Monomer: the acidic chain inhibits the basic phospholipase A2 of the complex. Heterodimer of a weakly toxic basic protein having phospholipase A2 activity (B chain) and a non-toxic acidic protein functioning as its inhibitor but which potentiates its lethal potency and neurotoxicity (A chain). Expressed by the venom gland. Belongs to the phospholipase A2 family. Group II subfamily. D49 sub-subfamily.