The rare Caribbean sponge Leucosolenia canariensis: phospholipid fatty acids and sterols.

The phospholipid fatty acid composition of the Calcarean sponge Leucosolenia canariensis was studied, and no delta 5,9 fatty acids were detected. These results are in contrast to the phospholipids from sponges belonging to the class Demospongiae where delta 5,9 fatty acids are predominant. Odd branched-chain fatty acids between 17 and 19 carbons accounted for 26% of the total fatty acids of L. canariensis, while straight-chain fatty acids between 16 and 22 carbons accounted for 61% of the total fatty acid composition. The sterol composition of L. canariensis is also reported, and only delta 5,7,22 sterols were observed.