- Reference
- Rhodomelac.Golfes Neapel 637 (1901)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus medium to dark red-brown, tufted, 2–6 cm high, with several erect axes, ecorticate, more-or-less complanately branched, arising from prostrate axes. Attachment by rhizoids; epizoic or epiphytic on seagrass or algae. Structure. Apices of axes and lateral branches sympodial and distichous, developing 7–8 pericentral cells beginning 5–10 cells below the apices, mature segments 150–350 µm in diameter and L/D 0.4–1.2(–2). Pseudolaterals (2–)4–7 segments apart, 1.5–3 mm long, becoming polysiphonous below but with simple (occasionally branched) terminal filaments of 6–12(–20) cells, lower segments 100–130 µm in diameter and L/D 0.5–0.8, tapering markedly to subapical cells 35–90 µm in diameter and L/D 0.5–1. Pseudolaterals with adaxial and distichous branches, usually with a secondary sympodial axis arising adaxially on the fourth (occasionally third) segment from their base, and with the primary branch of the pseudolateral extending in length and becoming hamate, cells 100–140 µm across and L/D 0.5–1. Attachment rhizoids arising from cells of pseudolaterals, with multicellular haptera. Rhodoplasts discoid, in chains in larger cells.
Reproduction. Gametophytes unknown. Tetrasporangial stichidia developing from a polysiphonous branch of the pseudolaterals, (350–)500–1500 µm long and 100–180 µm in diameter, lanceoid to cylindrical with a short polysiphonous pedicel and short blunt apex, occasionally continuing growth with a simple or branched filament; tetrasporangia 5 per segment, each with 2 pre-sporangial cover cells which divide horizontally giving 4 squat cells covering each sporangium.
Distribution. King George Sound, W. Aust., to Gabo I., Vic., and around Tas.
[After Parsons & Womersley in Womersley, Mar. Benthic Fl. Southern Australia IIIC: 481–483 (1998)]