Enter Search Terms:
Genus (i.e. Fucus)
Species (i.e. Gardneri)
Common Name (i.e. Rock Weed)
Phylum (i.e. Ochrophyta)
All of the above
Tar Spot Alga
Petrocelis phase
Authority:
North Pacific Distribution:
Bering Sea and Aleutian Is., Alaska, to Baja California, Mexico; Japan; Russia.
Phylum:
Rhodophyta
Class:
Florideophyceae
Order:
Gigartinales
Family:
Phyllophoraceae
Former Scientific Names:
Description: Thallus is a thick (to 2 mm or 0.08 in), brownish to blackish crust that is actually the alternate reproductive phase (the tetrasporophyte) of the Turkish Washcloth (Mastocarpus). The crust is firm but not hard: one can sink one’s fingernail into it. Its surface is smooth but sometimes shows faint concentric scalloping. Habitat: This very resilient, perennial phase can be extremely long lived, to 90 years or more; it is common on high to low intertidal rock in protected to semi-exposed habitats. Similar taxa:  Ralfsia
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