Abstract

Rugulopterix okamurae is a macroalga native to the northwestern Pacific and recently found in Southeast (SE) Spain. This macroalga poses a serious threat because of its strong capacity to alter the community structure of marine ecosystems. This species is difficult to distinguish from native elements such as Dictyota spp.; thus, a simple tool for identifying these algae will be welcome. In this work, the fatty acid (FA) composition of R. okamurae and Dictyota spp. samples from several locations were determined and discussed from a chemotaxonomic point of view. In R. okamurae highlights palmitic, oleic, and arachidonic (ARA) acids, while in D. dichotoma eicosapentaenoic acid and ARA reached higher values than in R. okamurae. Further, Agglomerative Hierarchical Clustering analysis performed for selected FA ratios segregated R. okamurae from any Dictyota species, especially due to ARA + EPA proportions, thus FA profiling constitutes a valid chemotaxonomic tool for rapid identification of R. okamurae.