Marseniopsis mollis

McClintock, J. B., Baker, B. J., Hamann, M. T., Yoshida, W., Slattery, M., Heine, J. N., Bryan, P. J., Jayatilake, G. S., and Moon, B. H., Homarine as a feeding deterrent in common shallow-water Antarctic lamellarian gastropod Marseniopsis mollis a rare example of chemical defense in a marine prosobranch, J. Chem. Ecol., 20, 2539, 1994. 

The bright yellow lamellarian gastropod Marseniopsis mollis collected at McMurdo Sound produces the feeding deterrent homarine.51 Homarine is widely distributed in marine phyla and has been suggested to serve as an osmolyte.165... 

In the bright yellow lamellarian Marseniopsis mollis, soft mantle tissue covers a reduced shell, which makes this species, similar to opisthobranchs, susceptible to predation. In the first demonstration of chemical defense in a prosobranch mollusc, ecologically relevant concentrations of homarine, which is present in high concentrations in the tissues of Marseniopsis mollis, caused... 

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