- Reference
- Liste Alg.Siboga 3:332-333, Figs 123, 124 (1923)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus with limited prostrate axes bearing simple erect axes to 4.5 mm tall, these typically clavate, 110–300 µm diam. at their broadest point, with straight pointed apices and tapering basally to 50–100 µm diam. Lateral adventitious branches often produced from lower axial cells, forming prostrate axes. Axial cells of erect axes extremely variable, in broadest parts of axes lenticular, 120–250 µm diam. [L:B 0.5–1], in basal parts narrower, 50–100 µm diam. and longer [L:B c. 1]. Attachment by unicellular rhizoids arising 1–5 per node on periaxial cells of prostrate axes and lower nodes of erect axes. Axial cells of prostrate axes 50–80 µm diam. [L:B 1–1.5]. Nodes with 8 or 9 periaxial cells (although as few as 5 in prostrate axes) these cutting off 2 acropetal and initially 2 basipetal initials; in well-developed nodes the initials dividing several times to produce a node of up to 9 layers, often with acropetal cells cutting off occasional cells in various directions and partially covering the periaxial cells, and a third basipetal initial arising from periaxial cells. Nodes in distal parts of erect axes often almost confluent, the node margins only distinguishable by the differing cell shapes; elsewhere and in lower parts of the thallus with clear internodal spaces. In poorly developed nodes, mostly those in prostrate filaments, basipetal development is absent and the periaxial cells each cut off only 2 acropetal cells.
Reproduction. Tetrasporangia forming in acropetal whorls on periaxial cells and acropetal initials, with up to 16 sporangia per node, spherical to ellipsoidal, 35–50 µm diam. (including the wall), cruciately divided, mostly immersed in the node or slightly emergent, causing a slight distortion. Other reproductive structures not observed.
Distribution. Known from the Indian Ocean and South China Sea.
Habitat. Epiphytic on various algae.
[After J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 392–395 (2018)]