Biodiversity Associated with Southern Mexican Pacific Coral Systems

Abstract

Shallow coral reefs worldwide occupy 1.2% of the world’s continental shelf area but support an estimated 35% of all known marine biodiversity. Nevertheless, our knowledge of reef-associated biodiversity in southern Mexican Pacific systems is scarce. Here, we synthesize the knowledge regarding the biodiversity of reef-associated organisms including algae, sponges, cnidarians, polychaetes, mollusks, malacostraceans, echinoderms, and fishes across coral systems located in Guerrero and Oaxaca. To date, 97 localities have been referred as harboring reef corals in the area, and 18 sites can be considered as harboring true reefs dominated by Pocillopora spp. (>90%) and to a lesser extent by Pavona spp. (<5%) and Porites spp. Coral systems harbors 989 operational taxonomic units (177 algae, 40 sponges, 36 cnidarians, 131 polychaetes, 196 mollusks, 126 malacostraceans, 73 echinoderms, and 210 fishes). Nonparametric models indicate that richness is far from reaching the asymptote in all taxonomic groups, particularly in algae (22.5%) and polychaetes (56%), although cnidarians (83.7%) and fishes (82.6%) are relatively close to reach the richness suggested by the models. Species richness patterns, if any, are influenced by sampling bias. Finally, it is expected that future sampling of unprospected habitats, sites, and taxa employing traditional and novel techniques may render far more species than expected. Additionally, biodiversity should be seen as a master variable for practically evaluating both the health of ecosystems and the success of management efforts, and hence, a standardized and systematic monitoring protocol under a marine biodiversity observation network is necessary for effective reef management.