Crustacean-selective presynaptic neurotoxin that induces neurotransmitter exocytosis. May bind to crustacean neurexin-1 homolog, adhesion G protein-coupled receptor L1 homolog, and receptor-type tyrosine-protein phosphatase S homolog, and induces neurotransmitter exocytosis both by forming tetrameric pores in membranes and signaling via G protein-coupled receptor (By similarity) (PubMed:34845192). This recombinant protein form channels in artificial membrane bilayers, that are stabilized by calcium ions and allow calcium flux at negative membrane potentials (PubMed:34845192). Homotetramer in membranes. Forms a membrane channel in the prey. Expressed by the venom gland. The H8 helix is predicted to insert into membranes and form pores by assembling into tetramers. The helix is contained within a helical bundle domain that undergoes significant conformational changes during pore formation to allow exposure of the H8 transmembrane helix and transition of the toxin from a soluble monomer to a transmembrane tetramer. LD(50) is 100 ug/kg to the crayfish Procambarus cubensis. Belongs to the cationic peptide 01 (latrotoxin) family. 01 (alpha-latrocrustotoxin) subfamily.