- Reference
- Austral.J.Bot. 210 (1959)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus medium red to red-brown, when detached rapidly disintegrating, mucilaginous, 2–20 cm high, slender, much branched irregularly to unilaterally, with older terete axes and branched upper parts bearing 2 rows of monosiphonous filaments, lost from lower parts. Holdfast rhizoidal, spreading, discoid; epiphytic. Structure. Apical development as in S. tenera but with only the lateral flanking cells producing monosiphonous filaments, at first alternately from each upper flanking cell, later from both sides of each segment; filaments 14–20 µm in diameter, cells L/D 3–6. Lateral branches endogenous. Cortication commences many segments below the apices, becoming heavier on the terete lower axes. Cells uni- or binucleate in filaments, multinucleate in larger cells; rhodoplasts discoid, becoming chained.
Reproduction. Gametophytes dioecious. Procarps produced as in S. tenera, with the adaxial pericentral cell producing 2 sterile cells and the 4-celled carpogonial branch, the carposporophyte and cystocarp identical with those of S. tenera. Spermatangial blades also similar in structure to S. tenera. Tetrasporangial stichidia slightly longer and more corticated than in S. tenera, otherwise identical in structure; tetrasporangia 65–90 µm in diameter.
Distribution. King George Sound, W. Aust., to Westernport Bay, Vic., and N Tas.
Habitat. S. dolichocystidea usually occurs in more sheltered situations than S. tenera.
[After Womersley, Mar. Benthic Fl. Southern Australia IIID: 157–158 (2003)]