ORIGIN OF THE MONOENE FATS IN THE LIPID OF MIDWATER FISHES - RELATIONSHIP BETWEEN THE LIPIDS OF MYCTOPHIDS AND THOSE OF THEIR PREY

The lipid and fatty acid composition of the total Lipids in the tissue s (whole animal excluding stomach contents) and the stomach contents o f 13 myctophid species living in the mesopelagic zone were analyzed. T riacylglycerols (TAG) were the dominant deposit lipids in 10 myctophid species, while wax eaters (WE) were found to be the major neutral lip ids in 3 non vertically migratory species. Lipids from the myctophid s tomach contents were determined to contain mixtures of WE and TAG. Mon oenoic acids and alcohols were the major fatty components in both the TAG and the WE: of the lipids from the tissues and stomach contents of all of the specimens examined. Lipid classes in the stomach contents originating from prey were different from those in myctophid tissues, but the level of monoenes in stomach content lipids was very similar t o those in the tissue lipids. This finding suggests that myctophids ma y transfer dietary lipids to specific lipid classes, without biosynthe tic modification such as carbon chain elongation or desaturation.