Floristic and phytogeographic aspects of the seaweeds of the bays at Santa Catarina Island, SC, Brazil

Abstract

Santa Catarina's coast presents a great number ofworks involving seaweeds, however, Santa Catarina Island Bay was poor1y described and represents an environment that comes suffering severe humans interferences with the urbanization advances. The present work had for objective to carry through the survey of the seaweeds of this bay, contributing for the knowledge of the marine biodiversity of the State and the south of the country. Twelve stations had been selected to represent the distinct physiognornies inside the bays. 107 taxa infrageneric had been identified. Some taxa are cited for the first time to south region, as Pleonosporium polysthicum E. C. Oliveira, Acinetospora crinita (Carmichael ex Harvey in Hooker) Kommann and Neosiphonia sphaerocarpa (Børgesen) M. -S. Kim & I. K. Lee. Feldmann and Cheney's index for Santa Catarina Island Bay had characterized it as part of the Warm Temperate province, as well as analyzed previously for other authors, however presenting inferior values to these studies. More urbânized areas had demonstrated to be outside of the described phytogeographic standards previously, mainly due to distinct vulnerability that some groups of seaweed present situations ahead of stress, such as the Phaeophyceae. It means the urbanization impacts of coastal environments have the potential to modify the ecological and even biogeographic standards of marine environments, representing important forces in the modem processes of natural selection.