Styela clava (Tunicata: Ascidiacea)—a new addition to the fauna of the Portuguese coast

Abstract

The solitary ascidian Styela clava is recorded for the first time in Portuguese waters. It was found at three sites on the west coast of Portugal. This represents the southern limit of its recorded distribution in European waters. The Portuguese specimens are described and compared with UK specimens.

The alien ascidian Styela clava now invading the Sea of Marmara (Tunicata: Ascidiacea)

“…This species has been introduced to different parts of the world’s oceans, including the east Atlantic coast (see Minchin et al 2006), Australia (Hewitt et al 1999), New Zealand (Davis and Davis 2006), both coasts of North America (Osman et al 1989; Lambert and Lambert 1998; Lambert 2003; Wonham and Carlton 2005), Mediterranean Sea (Davis and Davis 2008) and the Black Sea (Micu and Micu 2004). As Davis and Davis (2008) summarized, there are two possible mechanisms of ascidian introduction; shellfish transportation (juvenile ascidians) or via ship’s hulls and sea chests (mature ascidians) (Coutts and Dodgshun 2007).…”

First record of the Australian ascidianEudistoma elongatumin northern New Zealand

“…A number of ascidians appear to have been introduced into New Zealand waters and many were first discovered close to port areas (Cranfield et al 1998;Kott et al 2006), which are considered to be at greatest risk of invasion by exotic species. For example, the leathery tunicate Styela clava was first detected in Hauraki Gulf, close to Auckland, in 2005 (Davis & Davis 2006) and has subsequently been found in the ports of Lyttelton and Nelson, in the South Island and the Tutukaka marina in northern New Zealand (g. inglis, NiWA pers. comm.…”

The impact of the ascidian Styela clava Herdman on shellfish farming in the Bassin de Thau, France

“…On mainland Europe S. clava have been reported as widespread in the Limfjord (Lützen and Sørensen, 1993) and in the Kattegat (Lützen, 1999) in Denmark. To the South, it has been reported in the ports of Ostend, Belgium (Eneman, 1995); Dunkerque, France (Davoult et al., 1993), Pornichet, Pornic and La Rochelle in France (Davis and Davis, 2004); Ría de Ferrol, in northwest Spain (Vázques and Urgorri, 1992); Santander, Gijon, Muros and Sada in northeast Spain (Davis and Davis, 2004); and Leixões (Porto), Cascais and Lisboa in Portugal (Davis and Davis, 2005). It is now well established in European waters but we have not recorded any populations in fifty Mediterranean harbours that we have surveyed (Davis et al., 2007).…”