Eye phospholipids and fatty acids from taxonomically-related Finnish and Japanese crayfish of similar habitats, but separated by 25 degree of latitude

摘要

Eye lipids and their fatty acid composition were analysed in the Japanese Procambarus clarkii and the Finnish Astacus fluviatilis, two taxonomically related species of crayfish occurring in similar habitats, but separated geographically by 25 degree of latitude. Of the total lipids in the P. clarkii eye 43% were phosphatidylcholine-lipids (PC) and 19% were phosphatidylethanolamine-lipids (PE), whereas these phospholipids in A. fluviatilis were 18% and 52%, respectively. In the cooler waters of Finland, Astacus may have difficulties converting PE-lipids to PC-lipids, a problem that P. clarkii may not have in the warmer Japan. In this respect, eye lipids from Artemia reared at 27 degree C resemble those of P. clarkii, while Astacus eye lipids are similar to those of the cold deepwater prawn Pandalus. The analysis of the fatty acids suggests that A. fluviatilis at 17 degree C had a greater need to stabilize its membranes than P. clarkii at 25 degree C.