A neurotoxin that is novel in structure and potency and which acts at voltage-gated Na+ channels, was reported at the 2000 International Chemical Congress of Pacific Basin Societies, which is comprised of the national chemical societies in the United States, Australia, Canada, Japan and New Zealand. The toxin was extracted from the marine cyanobacteria Lyngbya majuscula, the blue-green algae commonly known as ‘pond scum,’ in the Caribbean island of Curacao. It has been named ‘kalkitoxin’ in honor of the islands Kalki Bay in which it was found. The lethal toxin targets Na+ channels in brine shrimp and prevents nerves cells from generating and propagating action potentials. Known toxins have been instrumental in teaching neuroscientists how these channels work and kalkitoxin, which is structurally unrelated to these toxins, may reveal additional insights. The compound might also have therapeutic potential because other Na+ channel blockers have been used as painkillers and anti-epileptics.