- Reference
- Proc.Natl.Acad.Sci.U.S.A. 447 (1942)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus medium to dark red-brown, 8–15 cm high, complanately and irregularly branched usually 5–20 mm apart, with elongate branches increasing in width upwards from 2–5 mm broad basally to 6–15 mm broad near the rounded apices, margins entire, smooth. Midrib inconspicuous above, thickened near the base and 2–3 mm broad; microscopic veins absent. Holdfast fibrous, 2–8 mm across; epilithic. Structure. Growth marginal, without conspicuous apical cells, with smaller cells marginally increasing to irregularly arranged angular cells 10–25(–30) µm across and L/D 1–1.5(–2). Blades soon tristromatic, later polystromatic (3–7 cells) and 35–55 µm thick, with corticating cells tiered and equivalent in size to central layer which is not distinctive; midrib areas many cells thick.
Reproduction. Gametophytes unknown. Tetrasporangial sori on ovate marginal leaflets 1–3 mm across, several cells and 300–400 µm thick, with short terete stipes, arising on the blade surface; tetrasporangia occupying most of the leaflet, of varying ages, cut off from cortical cells, subspherical and 45–75 µm in diameter.
Distribution.Dongara to the Swan R. region, W. Aust., and Head of the Great Australian Bight, S. Aust.
Habitat. B. cartilagineum is apparently a rare, deep-water species.
[After Womersley, Mar. Benthic Fl. Southern Australia IIID: 145–146 (2003)]