Laurencia

Laurencia is a genus of red algae (Rhodophyta) that comprises numerous species distributed in tropical and subtropical marine waters worldwide. Members are typically found in shallow coastal habitats on rocky substrates, coral reefs, or among loose substrata, from the intertidal to subtidal zones.

Laurencia species exhibit a range of thallus forms, from crustose encrustations to articulated or dichotomously branched filaments, usually displaying reddish to dark reddish coloration. They contribute to primary production in reef and rocky shore ecosystems and can host diverse microfauna on their surfaces.

Laurencia is notable for producing an array of halogenated secondary metabolites, especially brominated sesquiterpenes and diterpenes. These compounds are part of chemical defense against herbivores and fouling organisms and have attracted interest for potential antimicrobial, antifouling, and cytotoxic activities in natural products research.

The genus belongs to the red algal order Ceramiales. It includes many described species, with Laurencia obtusa commonly cited as a reference species. Molecular phylogenetics has helped resolve relationships within Ceramiales and refined the taxonomy of Laurencia, which remains a subject of ongoing study due to morphological variability among species.