- Reference
- Syll.Alg. 847 (1903)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus dark red to brown-red, drying very dark, 10–40(–120) cm high, irregularly radially branched for 3–4 orders, branches terete, usually with one to a few percurrent axes with often distant laterals, lower axes 0.7–1.5(–2.5) mm in diameter, grading to lesser branchlets 300–500 µm in diameter. Holdfast discoid, becoming divided, 2–10 mm across, with lateral branchlets from the lowermost axis adhering by small haptera; epilithic or epiphytic on Amphibolis. Structure. Apices slightly pointed to just depressed, inner cortical cells often as a ring of larger cells with surrounding rhizoids in older axes; epidermal cells 10–15 µm in diameter and L/D (5–)9–17. Trichoblasts profuse in apical depressions, 0.5–1 mm long. Cell wall thickenings not observed. Cells with discoid rhodoplasts, chained in larger cells.
Reproduction. Gametophytes dioecious. Procarps situated several cells along trichoblasts. Carposporophytes with a basal fusion cell and branched gonimoblast with clavate terminal carposporangia 35–60 µm in diameter. Cystocarps ovoid to slightly urceolate, 0.8–1.5 mm in diameter, short-stalked with a prominent, curved, spur; pericarp ostiolate, mostly 2 cells thick, lightly corticate basally. Spermatangial plates discoid to cordate, 350–750 µm across, with 1(–2) sterile marginal cells. Tetrasporangia in lesser branchlets, on (2–)3 pericentral cells per axial cell, 90–140 µm in diameter.
Distribution.King George Sound, W. Aust., and Spencer Gulf, S. Aust., to Westernport Bay, Vic., and around Tas. New Zealand.
Habitat. C. harveyana is confined largely to sheltered situations often where there is strong current flow.
[After Womersley, Mar. Benthic Fl. Southern Australia IIID: 443 (2003)]