Description: English: Porphyra umbilicalis (right) and Porphyra purpurea (in front), Heligoland (Germany) Deutsch: Porphyra umbilicalis (rechts) und Porphyra purpurea (vorne), Helgoland, Felswatt. Date: August 1989. Source: Own work. Author:
Gabriele Kothe-Heinrich.