Conus Envenomation of Humans: In Fact and Fiction

Prominent hallmarks of the widely distributed, mainly tropical marine snail genus Conus are: (1) its unusually high species diversity; it is the largest genus of animals in the sea, with more than 800 recognized species; and (2) its specialized feeding behavior of overcoming prey by injection with potent neurotoxic, paralytic venoms, and swallowing the victim whole. Including the first report of a human fatality from a Conus sting nearly 350 years ago, at least 141 human envenomations have been recorded, of which 36 were fatal. Most Conus species are quite specialized predators that can be classified in one of three major feeding guilds: they prey exclusively or nearly so on worms, primarily polychaete annelids, other gastropods, sometimes including other Conus species, or fishes. These differences are shown to relate to the severity of human envenomations, with the danger increasing generally in the order listed above and a strong likelihood that all of the known human fatalities may be attributable solely to the single piscivorous species C. geographus.