Dictyota bartayresiana

Thallus prostrate, overlapping, compact or loosely clumped, relatively fragile, light brown, sometimes greenish, iridescent, to 20 cm high. Branching dichotomous, at 45-90º angle. Branches strap-shaped, 3-5(-7) mm wide, 85-150(-200) μm thick, terminal branches slightly twisted. Margins smooth, spiny or proliferous. Apices broadly rounded or acute. Surface cell rectangular, 12-18(-27) μm wide and 24-50(-75) μm long, in regular rows. Medullary cells rectangular, 110-140 μm wide, 125-155 μm thick, colorless, longitudinally elongated. Surface hairs in tufts, scattered. Sporangia spherical, tetrahedrally divided, 65-80 μm diam., dark brown; solitary or in groups, not surrounded by sterile paraphyses, on dorsal surface of the thallus. Rhizoids issuing from margins and ventral side of basal portions of thallus. Growing on hard substrate or epiphytic on larger algae, in shallow water of sheltered localities to subtidal.

Tropics and subtropics of Atlantic, Indian and Pacific Oceans.