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Electronic Flora of South Australia Genus Fact Sheet
Phylum Rhodophyta – Order Ceramiales – Family Ceramiaceae – Tribe Sphondylothamnieae
Thallus erect, much branched with distichous axes, each axial cell bearing 4–5 whorl-branchlets pinnately to subdistichously branched, terminal cells acute; indeterminate branches formed in position of whorl-branchlets; cortication of older axes by descending rhizoids from basal cells of whorl-branchlets; haptera without a terminal digitate disc. Cells multinucleate.
Reproduction: Procarps subapical on short lateral branchlets or laterals of whorl-branchlets, subapical cell with 3 pericentral cells, 2 sterile and the third (the supporting cell) bearing a terminal sterile cell and a lateral carpogonial branch; hypogenous cell elongate and without any laterals. Gonimoblast with a basal fusion cell and clavate carposporangia. Sterile cells associated with the procarp divide post-fertilization to form four inner involucral branchlets. Spermatangia unknown.
Tetrasporangia borne on lower cells of whorl-branchlets, adaxial, tetrahedrally divided.
Type species: D. nitella (Harvey) Gordon 1972: 101.
Taxonomic notes: Drewiana contains a single species, and is distinguished from related genera by the elongate hypogenous cell without any laterals, by the single auxiliary cell per procarp, and by the presence of pre-fertilization laterals on the sub-hypogenous cell.
References:
GORDON, E.M. (1972). Comparative morphology and taxonomy of the Wrangelieae, Sphondylothamnieae and Spermothamnieae (Ceramiaceae, Rhodophyta). Aust. J. Bot. suppl. 4, 1–180.
The Marine Benthic Flora of Southern Australia Part IIIC complete list of references.
Publication:
Womersley, H.B.S. (24 December, 1998)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIIC. Ceramiales – Ceramiaceae, Dasyaceae
©State Herbarium of South Australia, Government of South Australia
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