Fuscidea cyathoides forme maritime.
This form is characterized by its thick, irregular, bumpy, whitish-ochraceous, very light chocolate brown, etc. thallus. with an often prominent brown-black to black hypothallus. The apothecia are numerous, disc flat then convex, often strongly convex and domed, sometimes a little deformed, brown-red then brown and finally blackish, sinuous margin, visible only at the beginning then disappearing quickly when the apothecia become convex. Characteristic of the vertical or strongly inclined faces of siliceous rocks receiving projections of sea water.
N.B. The extreme old and aged form of this maritime form appears to be Fuscidea cyathoides forme altérée.