Blocks voltage-gated potassium channels Kv1.2/KCNA2 (IC(50)=140 nM). Belongs to the sea anemone type 1 potassium channel toxin family. Type 1b subfamily. Opinions are divided on whether Anemonia viridis (Forsskal, 1775) and Anemonia sulcata (Pennant, 1777) are separate species.