New records of octocorals (Cnidaria, Anthozoa) from the south western Atlantic Ocean, with zoogeographic considerations

The present study deals with six new records of octocoral species (two alcyoniid soft corals and four primnoid gorgonians) for the south western Atlantic Ocean. These new records, mainly for the gorgonians, improves the knowledge of their present distribution. The species Thouarella koellikeri and Dasystenella acanthina have their known distribution widened, showing in the first case a continuous bioceanic distribution (south east Pacific - south west Atlantic). The species of the genus Primnoella, P. biserialis and P. compressa, widen their distributional range tending to a geographical continuity along the south eastern coasts of the American continent, avoiding the zoogeographic barrier constituted by the Rio de la Plata.