Scageliopsis patens (Ceramiales, Rhodophyta), a new introduced species along the European coast

Scageliopsis patens, previously known from southern Australia and reported for the North Atlantic at the Azores Islands, is recorded for the first time along the European coast. This new alien species was collected in the subtidal and lower intertidal zones at seven Atlantic locations of the Iberian Peninsula, within the warm Atlantic Iberian area (Cantabrian Sea and south of Portugal). A comparison is made with the two other species of the genus Scageliopsis as well as morphologically similar Antithamnionella species in order to differentiate it from similar ceramiacean species.