Analysis and characterization of methyl esters of fatty acids of some Gracilaria species

► Species of Gracilariaceae show analogous chemotaxomic basis. ► Hexadecanoic acid is the major compound found in all studied species. ► We support the hypothesis of G. cervicornis and G. domingensis as sister groups. ► We isolate H. caudata from the others regarding its taxonomic position. ► G. birdiae occupies an intermediate position between the groups.