Codium capitulatum P.C.Silva & Womersley

Scientific Description

Habit and structure. Thallus firm, dark green, applanate and lobed, closely adherent to rock, to 1 cm thick and to 15 cm across. Utricles in large clusters; primary utricles 70–140 µm in diameter at apices, constricted 50–85 µm below apices, usually expanded below to 230 µm in diameter, 600–1300 µm long; secondary utricles 40–85 µm in diameter at apex, prominently constricted just below apices and capitate, expanding to 115 µm in diameter below, 600–1000 µm long, separated from adjacent utricles by a plug; wall of utricles thin, not or only slightly thickened at apices; hairs (or scars) prominent just below constriction on primary and often on secondary utricles. Medullary filaments distinctly slenderer than utricles, 16–45 µm in diameter, without plugs.

Reproduction. Gametangia fusiform, 60–110 µm in diameter, 240–380 µm long.

Distribution. From Hopetoun, W. Aust., to Walkerville, Vic.

Habitat. Occurs in the lower eulittoral and uppermost sublittoral on rock platforms on rough-water coasts, often where shaded and with slight shelter.

[After Womersley, Mar. Benthic Fl. Southern Australia I: 226 (1984)]