Description: English: Mastocarpus papillatus, "Turkish washcloth". High intertidal at Moonstone beach in Cambria. IB this is the female form. Note "tar spot" on rock to left of alga. This is likely the "Petrocelis" crust, an alternate life stage that reproduces asexually via spores. Ref: Petrocelis According to some sources, the gametophyte (frond) phase prefers to grow on the "tar spot" phase. [1]. Date: 24 May 2015. Source: Own work. Author: Peter D. Tillman. Camera location35° 34′ 21.32″ N, 121° 06′ 48.17″ WView all coordinates using: OpenStreetMap - Google Earth 35.572589; -121.113381.
