Description: Thallus is usually burgundy red, somewhat rubbery, not iridescent, to 15 cm (6 in) tall and nearly as wide. Blades are deeply cleft into irregular, often pointed lobes. Reproductive blades have large cystocarps 4 mm (0.16 in) in diameter bulging from the blade surface. Habitat: This species grows on rock in the low intertidal, often in tidepools, of semi-protected to semi-exposed habitats; it also occurs subtidally. Similar taxa: Mazzaella oregona, M. parvula< M. parksii.