Gracilaria spinulosa

Thallus flattened, foliose, cartilaginous, erect, 6–11 cm high, shortly stipitate, brownish-red, greenish-brown to dark purple. Branching irregularly dichotomous. Branches flattened, 0.5–1.2 mm width, 245-370 μm thick, with obtuse or ligulate tips. Short spinous branchlets develop marginally and superficially from the blade. Tetrasporangia cruciately, irregularly cruciately divided, embedded in cortex, roundish, to oval (17.5–20x20–22 μm), scattered over the thallus. Cystocarps single or in groups, subspherical, prominent, constricted at the base, 450–600x680–770 μm. Attachment by small disc-like haptera. Growing in upper subtidal on dead corals, in calm areas.

Note: This species has potential as human food.

North America (Gulf of California). Subtropics and tropics of Indian and Pacific Oceans. Found in China, Taiwan, Vietnam, Philippines.