- Reference
- Bot.Antarct.Voy.III.(Fl.Tasman.) 297-298 (1859)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus medium to dark red to red-brown, 10–30 cm high, with one to several erect axes irregularly radially branched for 3–4 orders, lower parts of axes often sparsely branched, upper often with long laterals; lower axes 0.8–2 mm in diameter, grading to lesser branchlets 200–600 µm in diameter; base of axes usually swollen to 3 mm in diameter and 5–15 mm long with starch-filled cells, and bulbous swellings 0.6–1(–2) mm in diameter often occur on upper branches in tetrasporangial plants. Holdfast discoid to conical, 1.5–4(–10) mm across; epilithic, usually in deep water. Structure. Apices attenuate to slightly depressed, mature epidermal cells 20–30 µm in diameter and L/D (1.5–)3–8; axes with slight to moderate rhizoid development around the pericentral and inner cortical cells; secondary cortex extensive on lower axes in some plants. Cells of the basal and upper swellings usually starch-filled (except the epidermis); these may act as storage organs or propagules. Cell wall thickenings absent or occurring as band-like caps or bands around the centre of pericentral (and some inner cortical) cells. Cells with discoid rhodoplasts, chained in larger cells.
Reproduction. Gametophytes dioecious. Procarps not observed. Carposporophytes with a basal fusion cell and short, branched, gonimoblast with clavate terminal carposporangia 35–50 µm in diameter. Cystocarps broadly ovoid to slightly urceolate, 0.8–1.25 mm in diameter, short-stalked, without a spur; pericarp with a broad ostiole, 2 cells thick, ecorticate. Spermatangial plates developed from a basal branch of a trichoblast, irregularly reniform, 500–750 µm across, with a sterile margin usually 1(–2) cells broad. Tetrasporangia in lesser branchlets, on 2–3 pericentral cells per axial cell, 180–250(–400) µm in diameter.
Distribution.Port Denison, W. Aust., to Cape Jaffa, S. Aust., and E Tas.
Habitat. C. bulbosa is a deep-water species.
[After Womersley, Mar. Benthic Fl. Southern Australia IIID: 429 (2003)]