- Reference
- Austral.J.Bot. 389-391; fig 38 I-P (1968)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus with prostrate axes and erect branches to 5 mm high, each axial cell bearing (2–)3(–4) whorl-branchlets with a longer central branchlet or indeterminate branch between a pair of short branchlets. Attachment by rhizoids of elongate cells with terminal branched haptera, arising from the basal cells of whorl-branchlets on prostrate axes; epiphytic. Structure. Apical cells 5–7 µm in diameter and L/D 1–1.2, enlarging after 6–8 cells to axial cells 25–55 µm in diameter and L/D 4–6, with the whorl-branchlets separated. Long whorl-branchlets 100–250 µm and 6–10 cells long but extending to indefinite branches, with each rachis cell bearing 2–3 short branches (1–)2–3(–5) cells long, sometimes further branched and often with 2(–3) small stalk cells with or without hairs; rachis cells 10–15 µm in diameter and L/D 4–6, basal cell shorter and usually unbranched, tapering to terminal cells 4–6 µm long and L/D 1.5–2; gland cells occur on branches of long whorl-branchlets or on short whorl-branchlets, usually on and touching only the subterminal cell below the terminal pair of small cells, ovoid, 8–12 µm in diameter. Lateral branches extending from long whorl-branchlets or arising on the basal cell of whorl-branchlets. Cells uninucleate; rhodoplasts discoid, elongate or in longitudinal chains in larger cells.
Reproduction. Carpogonial branches occur on the basal cell of a short-branchlet, the terminal cell forming a sterile cell on the supporting cell; apical axial growth ceases on development of the procarp. The auxiliary cell is cut off from the supporting cell and after fusion with the carpogonium forms a lower foot cell and upper central cell, which develops a terminal gonimolobe and 4–6 lateral rounded gonimolobes 50–80 µm across of ovoid carposporangia 18–22 µm in diameter, surrounded by 2–4 long whorl-branchlets from the axial cell below. Spermatangia unknown. Tetrasporangia are borne on the basal cells of short whorl-branchlets, sessile, ovoid, 35–40 µm in diameter, tetrahedrally to subdecussately divided.
Distribution.Houtman Abrolhos, W. Aust., to Rocky Cape, Tas. (at scattered localities).
[After Womersley, Mar. Benthic Fl. Southern Australia IIIC: 178–179 (1998)]