Comparisons between the fatty acid compositions of the muscle and ovary of the nonparasitic lamprey Lampetra planeri (bloch) and their counterparts in the anadromous and parasitic Lampetra fluviatilis (L.)

1. 1. The proportion of polyunsaturated fatty acids in the triacylglycerols and phospholipids of muscle and ovary were far lower in adult Lampetra planeri than adult Lampetra fluviatilis. 2. 2. The most abundant fatty acids in the triacylglycerols were 16:1 in the muscle and ovary of adult L. planeri and 18:1 in the muscle and 22:6 in the ovary of L. fluviatilis. 3. 3. The above interspecific differences reflect marked differences in the fatty acid compositions of the lipids ingested and stored during the respective preceding trophic phases, i.e. during microphagous larval life in L. planeri and during feeding on fish flesh in L. fluviatilis. © 1993