(2) Asparagopsis armata Harvey, 1855

Status in U.K. – non-native.

There have been two records of Asparagopsis armata (“harpoon weed”) from the monitoring programme, from buoys at Holm and Shapinsay, both from 2013. The species is believed to have been introduced to Europe from southern Australia or New Zealand in the 1920s (Ní Chualáin et al. 2004) and has otherwise been recorded in Orkney at Kirkwall and Skatelan Skerry by Wilkinson (1975) and Maggs and Stegenga (1999).