Long arms are almost round; usually with five arms, but occasionally four or six; lack pedicellariae. Color orange to red, often banded with other shades; diameter to about 200 mm.

Found on and under rocks, especially rocks encrusted with sponges and bryozoans. Feeds on small particles and bacteria.

Low intertidal to 400 m; Aleutian Islands, Alaska to Baja California, Mexico.