Biodiversity and spatial distribution of medusae in the Magellan Region (Southern Patagonian Zone)

Epipelagic medusae collected in the Magellan Region (Southern Patagonian Zone) during spring 2009 were analyzed. A total of 27 species of medusae were identified (25 hydromedusae and 2 scyphomedusae). Twelve medusae species were recorded for the first time in the Magellan region. Six dominant species were found: Clytia simplex (19.8%), Rhopalonema funerarium (16.2%), Aurelia sp. (15.9%), Bougainvillia muscoides (15.5%), Proboscidactyla stellata (8.9%), and Obelia spp. (6.0%). The horizontal distribution of all these species, except Obelia spp., showed the highest abundances to the south of 54°S, particularly in the Almirantazgo and Agostini fjords and in the Beagle Channel. Most of the dominant species were collected in shallow strata (0-50 m), with less saline waters (<30), except for R. funerarium, which was mainly collected above depths deeper than 25 m in more saline waters (30-33). These results confirm the success of several species in the colonization of the inland waters of the Southern Patagonian Zone.