Constantinea rosa-marina

Cup and saucer

Authority: (S.G.Gmelin) Postels & Ruprecht

Thallus is dark red, saucer-shaped, with usually entire (not lacerated) blades less than 15 cm (6 in) diam., attached in the middle of their lower side to a branched, cylindrical stipe. Veins are inconspicuous. Thallus grows up to ~15 cm (6 in) tall. The stipe never protrudes. New blades develop each winter from the center of the previous year blade, and the stipe between the new and old blade elongates as the new blade expands.

Habitat

This perennial occurs on rock, mostly in the subtidal zone of semi-protected to semi-exposed habitats.

North Pacific Distribution

Bering Sea and Aleutian Islands to northern Southeast Alaska; Japan; Russia

Former scientific names

Fucus rosa-marina, Constantinea sitchensis

Similar taxa

C. simplex does not undergo stipe elongation; Constantinea subulifera has a protruding stipe from late spring until new blade formation in the winter.