The seasonality and role of the neurotoxin tetramine in the salivary glands of the red whelk Neptunea antiqua (L.).

The red whelk Neptunea antiqua (family Buccinidae) is a sublittoral species of marine prosobranch mollusc that occurs in the cold temperate waters of the Eastern Atlantic Boreal Region. A clearly defined seasonal cycle was revealed in the concentration of the whelk's salivary gland neurotoxin, tetramine, ranging from undetectable levels to 6530 microg/g over the course of an annual sampling period in the central western Irish Sea. Concentrations of this amine were indirectly related to feeding activity through the use of digestive gland indices. Additionally, laboratory observations confirmed the suspected ability of these whelks to actively predate on bivalves, supporting the use of this toxin in food procurement.