The non-indigenous ascidian Distaplia bermudensis in the Mediterranean: comparison with the native species Distaplia magnilarva and Distaplia lucillae sp. Nov

Three species of Distaplia from the Mediterranean are described: D. bermudensis is a species introduced from the western Atlantic Ocean, which principally di¡ers from the native D. magnilarva in having hermaphroditic zooids. The new species D. lucillae di¡ers from the preceding ones in the structure of its stomach wall which is regularly plicated both externally and internally. Distaplia lucillae has colonies with hermaphroditic, but only male ripe, zooids and exclusively female colonies; this is a condition closely related to D. magnilarva though di¡erent. A key to European Distaplia is provided