Macroalgae of the Campeche Bank, Gulf of Mexico.

Background: The coastal habitats in the southern Gulf of Mexico face multiple threats, such as rising water temperatures, acidification, increased turbidity, invasive species and pollutants. This imperils the biodiversity of beaches, wetlands and coral reefs. To address this, there is a need for comprehensive baseline information on marine biodiversity. Several reefs in the Gulf of Mexico have been extensively studied, yet smaller reefs on the Yucatan continental shelf lack thorough exploration despite their ecological significance. These reefs serve as crucial biodiversity hotspots influenced by environmental characteristics, receiving diverse taxa from the Gulf of Mexico.The macroalgae study at the Bank of Campeche dates back to the 1950s, but comprehensive investigations have been sporadic. The recent study aims to fill this gap, contributing to the taxonomic inventory of the area's benthic macroflora. Methodologically, extensive sampling across eight reefs was conducted, collecting and preserving macroalgae samples for identification in the laboratory.The study documented 90 infrageneric taxa across the reefs, with Cayo Arenas exhibiting the highest species count. Additionally, three new distribution reports for Mexico were identified in the region. The distribution of species varied amongst locations, with few species in common even amongst geographically proximate reefs. The diversity found in these reefs slightly trails behind other studied regions, but surpasses previous reports for the Campeche Bank.It is important to emphasise that the significance of this study lies in its focus on remote reefs with complicated and costly access logistics. Additionally, it is one of the first publicly available datasets published for this region.The study aligns with existing literature on prevalent families in reef environments and highlights differences in species distribution, based on depth variations amongst reefs. The findings of new distribution records in the region and the distinctiveness of localities despite their proximity underscore the unique ecological dynamics of these reefs.

New Information: These reefs are located in remote and difficult-to-access areas, highlighting the importance of the data obtained on their biodiversity and conservation status. This work presents for the first time a list of macroalgae for the reefs of Banco Nuevo, Banco Obispo, Banco Pera and Serpientes Reef. Three new distribution reports for Yucatan were identified at the Banco Obispo reef: E. Y. Dawson, (Montagne & Millardet) R. E. Norris and (W. R. Taylor) Huisman & Millar and a new report for the Mexican Atlantic, Setchell at the Triángulo Oeste reef. This results in distinct algal communities compared to other reefs in the region, emphasising their ecological significance and the need for continued research and conservation efforts. To our knowledge, this is one of the first interoperable datasets being published on the marine algae of the southern Gulf of Mexico reef ecosystems.