- Reference
- Remarques sur les Sphacelarialees 408-411, fig. 82 (1904)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus dark brown, (3–)6–20(–25) cm long, densely tufted with a rhizoidal holdfast 3–15 mm across and one to several erect, much branched axes, with adventitious laterals from mid and lower parts of axes, which often become denuded, usually epilithic. Branching of several orders, irregularly radial with laterals every (3–)5–10(–20) segments, with lesser laterals determinate and tapering to a point; mid (sometimes upper) and lower axes producing descending rhizoids which corticate the axes and form the holdfast; phaeophycean hairs absent. Axes 160–220 µm in diameter with segments L/B0.7–1.0, corticated by a layer of small, rectangular cells (without secondary cortex); primary laterals 100–140 µm in diameter with segments L/B0.6–0.8(–1.0); ultimate laterals 80–120 µm in diameter near their bases with segments L/B0.4–0.6(–0.8); rhizoids arising from pericysts.
Reproduction. Unilocular sporangia in dense sori (l50–250 µmradius) in axils of numerous consecutive laterals separated by (usually) 1–2(–3) soral diameters, each with a dense hemispherical mass of sporangia on simple or branched pedicels 2–7 cells long, with the sporangia at an even height, and without sterile paraphyses; sporangia subspherical, 40–50 µmin diameter. Sexual plants with mixed clusters of oogonia and antheridia in axils of laterals, borne on unbranched or basally branched pedicels 4–8 segments long, with occasional longitudinal divisions; oogonia subspherical, 65–110 µmin diameter; antheridia subspherical, less common than oogonia, 60–100 µmin diameter.
Distribution.From King George Sound, W. Aust., around southern Australia to Point Dromedary, N.S.W. and around Tas.
[After Womersley, Mar. Benthic Fl. Southern Australia II: 176–178 (1987)]