Accumulation of storage lipids is a key function in crustacean energy metabolism. Triacylglycerol (TAG) is the most common storage lipid in temperate species. It is synthesized via the Kennedy Pathway by the enzyme diacylglycerol acyltransferase (DGAT) and predominantly stored in the midgut gland. Previous studies have shown, that significant differences in total lipid content and lipid class composition can occur among species with similar feeding habits and overlapping habitats. An example are the two shrimp species from the southern North Sea, the brown shrimp Crangon crangon and the pink shrimp Pandalus montagui. The total lipid content as well as the proportion of TAGs are significantly lower in C. crangon than in P. montagui. Enzyme activity assays showed, that this difference correspond with lower activity of the DGAT enzyme. Transcriptome analyses revealed specific point mutations in DGAT sequences of C. crangon, which may affect enzyme activity. As a result, C. crangon is unable to accumulate large amounts of energy storage and, consequently, relies on a continuous food supply. Presumably, the inability to store lipids has also influenced the reproductive strategy of C. crangon towards a continuous, long-lasting reproductive period.