pharmacological re-classification of ion channels, based on work exploiting isoform selectivity and phyla differentia- tion characteristics (see Terlau and Olivera, 2004; Table 1). Yet, toxinologically what we know about the composition of these injected venoms remains mostly a mystery, particu- larly in this species which is known to be lethal to humans.
Potent biological activity has been correlated to the individually isolated secretory duct venom (DV) con- opeptides; these have offered some insight into their deadly nature. But there remain a number of compelling issues: Do the complex crude dissected DV extracts repre- sent what the snail uses in prey capture? Are all known DV conopeptides observed within a single milked venom (MV) collection? What makes a ‘killer’ cone snail lethal to humans? Here we address some of these questions using the MV of a known lethal cone snail, C. geographus – this species being responsible for at least 18 human fatalities (see Yoshiba, 1984).