Anisoschizus propaguli Huisman & Kraft

Scientific Description

Habit and structure. Thallus erect, 3 mm to 4 cm high, red-brown, slender and much branched subdichotomously, arising from short prostrate filaments attached by septate rhizoids; epilithic, on timber, or epiphytic on Sporochnus. Structure. Apical cells 10–25 µm in diameter and L/D 4–7, median cells 40–60 µm in diameter and L/D 3–5, lower and prostrate filament cells 50–130 µm in diameter and L/D 2–4. Cells multinucleate; rhodoplasts elongate, ribbon like in larger cells.

Reproduction. Propagules 2-celled, ovoid with the upper cell larger and 90–120 µm in diameter, borne on a short stalk cell on the upper end of branch cells. Gametophytes dioecious. Procarps borne on the subapical cell of short 2-celled axes, with the hypogenous cell bearing an elongate lateral cell. Subapical cell with 3 periaxial cells, one (the supporting cell) bearing a 4-celled carpogonial branch and a sterile cell. Post-fertilization, 2 auxiliary cells are cut off from the supporting cell and the opposite periaxial cell, and via connecting cells each develops 2 or 3 sequential gonimolobes 80–150 µm across, with ovoid carposporangia 16–30 µm in diameter. Carpogonial branch cells fuse and sterile cells of the procarp (apical, sterile periaxial and supporting sterile cells) produce 1–3 branched inner involucral filaments which envelop the carposporophyte. Spermatangial heads occur on adaxial ends of median thallus cells, elongate-ovoid, 25–35 µm in diameter. Polysporangia occur on the upper end of cells, subspherical, 40–60 µm in diameter.

Distribution.Hopetoun, W. Aust., to Western Port, Vic.

[After Womersley, Mar. Benthic Fl. Southern Australia IIIC: 307–310 (1998)]