Fatty acid composition of the Caprellidea (Crustacea: Amphipoda) from the Strait of Gibraltar

Abstract

SUMMARY:The total fatty acid composition of nine species of caprellidean amphipods collected from the Strait of Gibraltar was investigated. All caprellids were characterised by high levels of polyunsaturated fatty acids, mainly eicosapentaenoic acid, 20:5(n-3), and docosahexaenoic acid, 22:6(n-3); other major fatty acids were the saturate palmitic acid, 16:0, and the monounsaturate oleic acid, 18:1(n-9). In spite of this general uniformity, univariate and multivariate analysis showed that Caprella acanthifera and C. grandimana differed from the remaining species (C. danilevskii, C. equilibra, C. liparotensis, C. penantis, C. santosrosai, Phtisica marina and Pseudoprotella phasma). These two species (C. acanthifera and C. grandimana) showed higher concentrations of 18:1(n-7) and 20:4(n-6) and lower percentages of 22:6(n-3). These results, together with higher values of the biomarker ratio 20:5(n-3)/22:6(n-3) and a lower ratio 18:1(n-9)/18:1(n-7), suggested a greater contribution of diatoms and macroalgae in the diet of C. acanthifera and C. grandimana and a lesser contribution of flagellates than in the remaining species. The cluster classification of the caprellid specimens from the Strait of Gibraltar based on the fatty acid composition was in agreement with the Cluster output from data of feeding behaviour. Sex-related changes in the fatty acid composition were also explored in C. acanthifera, C. danilevskii and C. penantis; the percentage of 18:0, 20:4(n-6), and 20:5(n-3) was significantly higher in males, whereas 16:1(n-7) was higher in females. The intraspecific differences of fatty acids in different environmental conditions seem to indicate that the consumption of diatoms in contrast to flagellates increases with the degree of eutrophication.

Mediterranean fouling communities assimilate the organic matter derived from coastal fish farms as a new trophic resource

“…However, fish farming facilities such as ropes or buoys can support high densities of amphipods, especially caprellids, which are associated with fouling communities (Greene and Grizzle, 2007;Fernandez-Gonzalez and SanchezJerez, 2014). Caprellid amphipods are mainly detritivorous Tierno de Figueroa, 2009), andGuerra-García et al (2004) showed that caprellids generally present relatively high proportions of EPA and DHA, which agrees with our results in the control farm. In the active farm, significantly lower levels of DHA were found in C. equilibra, and of EPA in C. equilibra and C. dilatata, possibly due to a shift in diet, involving the greater consumption of feed wastes than in a natural diet (although the total fatty acid profile of C. equilibra showed no significant change between farms).…”

Dietary analysis of caprellids Caprella penantis and Caprella grandimana (Crustacea: Amphipoda) in southern Spain

“…These differences were also observed in fatty acid-based nutritional analyses by Guerra-García et al (2004) and BaezaRojano et al (2014). Caprella grandimana consumed more diatoms and macroalgae than C. penantis, which is more carnivorous.…”

Males and females gonad fatty acids of the sea urchins Paracentrotus lividus and Arbacia lixula (Echinodermata)

“…The level of 20:4n-6 is usually similar in males and females but the content of 20:5n-3 diVers among species and, for example, is higher in the testes of P. depressa and H. rubra but lower in those of A. purpuratus (Caers et al, 1999;Grubert et al 2004;Morais et al 2003). In several species of Caprellidea, we have also reported higher percentages of 16:1n-7 and lower levels of 18:0, 20:4n-6 and 20:5n-3 in females than in males (Guerra-García et al 2004). Sex diVerences in fatty acid composition of sea urchin gonads have only been Number of samples at La Herradura: 51.…”