Consistent genetic divergence observed among pelagic Sargassum morphotypes in the western North Atlantic

Skye Dibner (1) , Lindsay Martin (2) , Thierry Thibaut (3) , Didier Aurelle (3, 4) , Aurelie Blanfuné (3) , Kerry Whittaker (5) , Laura Cooney (5) , Jeffrey M Schell (5) , Deborah S Goodwin (5) , Amy N S Siuda (1)

1 Eckerd College
2 National Science Foundation
3 MIO - Institut méditerranéen d'océanologie
4 ISYEB - Institut de Systématique, Evolution, Biodiversité
5 Sea Education Association

Sargassum (class: Phaeophyceae, order: Fucales) is a complex group of marine brown macroalgae. There are 361 accepted species, mostly benthic, distributed globally in temperate and tropical waters (Guiry & Guiry, 2021). Among these, however, the world's only holopelagic macroalgae are as follows: Sargassum fluitans and S. natans. These drifters are suspected to reproduce asexually, maintain buoyancy via gas-filled floats, and establish a surface ocean habitat in the subtropical North Atlantic, equatorial Atlantic, Caribbean Sea, and Gulf of Mexico that is unparalleled in the open ocean. Individual, radial branching clumps are dispersed across the sea surface, aggregated by helical Langmuir circulation into parallel windrows, or concentrated into dense mats measuring 10s of meters across

Domains: Environmental Sciences; Biodiversity and Ecology; Life Sciences [q-bio]; Ecology, environment; Ecosystems

Skye Dibner, Lindsay Martin, Thierry Thibaut, Didier Aurelle, Aurelie Blanfuné, et al.. Consistent genetic divergence observed among pelagic Sargassum morphotypes in the western North Atlantic. Marine Ecology, 2021, ⟨10.1111/maec.12691⟩. ⟨hal-03474441⟩