Red sea tunicate

In 1988, Kashman et al. reported the isolation and structure elucidation of a novel, highly symmetrical, heptacyclic, aromatic alkaloid, eilatin (413) (ca 0.001% dry wt.), from the marine tunicate Eudistoma sp. collected in the Gulf of Eilat and/or the Straits of the Gulf of Suez, in the Red Sea 178,179). 

Mollusks that lack an external shell would be subject to predation were it not for the fact that many of these animals have elaborated chemical defenses, which most often are acquired through the diet, but occasionally are the result of biosynthesis. A dietary link was first suspected in 1965 between a sea hare and a red alga on which it grazes. Many similar relationships have been established between other herbivorous mollusks and their algal diet, as well as between carnivores and their prey, which include sponges, corals, tunicates and other sessile invertebrates. 

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