Abstract
In the estuary of the Swan River, Western Australia, the muricid caenogastropod Lepsiella (Bedeva) hanleyi has been found attacking the alien mytilid bivalve Mytilus galloprovincialis by shell drilling. Attacks were nearly always to the antero- and postero-dorsal regions of the mussel’s shell in either valve approximately equally. This is because ventral byssal attachment inhibits attacks in this location. No M. galloprovincialis individuals with shells of length >20 mm were attacked. A tenet of alien introductions is that success is possibly enhanced because native predators do not recognize them. This study confirms other studies and laboratory experiments on the congener Lepsiella vinosa that, provided the alien is morphologically similar to natural prey, one of which as here identified is Brachidontes ustulatus, then these generalist muricid predators can readily attack them.