Electronic Flora of South Australia Family Fact Sheet
Phylum Phaeophyta – Order Dictyosiphonales
Thallus (sporophyte) simple to (usually) much branched, 10–30 cm high, with slender, cylindrical, alternate, opposite or whorled polystichous branches, each with a terminal, uniseriate, filament many cells long, branches solid or becoming hollow, developed by longitudinal and transverse cell divisions below the terminal filament, forming a small-celled phaeoplastic cortex and a large-celled medulla. Phaeophycean hairs lateral, scattered. Growth trichothallic and diffuse.
Gametophytes microscopic, filamentous.
Reproduction: Sporophyte with unilocular or plurilocular sporangia or both, transformed from vegetative cells or exserted and with paraphyses, scattered or whorled. Unilocular sporangia often apomeiotic, producing asexual microthalli or macrothalli (Wynne & Loiseaux 1976, p. 443).
Gametophytes isogamous, with plurilocular gametangia [anisogamous in Hummia (Fiore 1977)].
Life history diplohaplontic and heteromorphic, or direct.
Taxonomic notes: A family of about 9 genera (Wynne 1982, p. 121), with two known from Australian harbours and possibly introductions (Skinner & Womersley 1983).
FIORE, J. (1977). Life history and taxonomy of Stictyosiphon subsimplex Holden (Phaeophyta, Dictyosiphonales) and Farlowiella onusta (Kützing) Kornmann in Kuckuck (Phaeophyta, Ectocarpales). Phycologia 16, 301–311.
SKINNER, S. & WOMERSLEY, H.B.S. (1983). New records (possibly introductions) of Striaria, Stictyosiphon and Arthrocladia (Phaeophyta) for southern Australia. Trans. R. Soc. S. Aust. 107, 59–68.
WYNNE, M.J. & LOISEAUX, S. (1976). Recent advances in life history studies of the Phaeophyta. Phycologia 15, 435–452.
WYNNE, M.J. (1982). Phaeophyceae. In Parker, S.P. (Ed.), Synopsis and classification of living organisms, Vol. I, pp. 115–125. (McGraw-Hill: New York.)
The Marine Benthic Flora of Southern Australia Part II complete list of references.
Womersley, H.B.S. (14 December, 1987)
The Marine Benthic Flora of Southern Australia
©Board of the Botanic Gardens and State Herbarium, Government of South Australia
KEY TO GENERA OF STRIARIACEAE
1. Lateral branches basally slightly attenuate, becoming hollow, with a small-celled cortex and medulla 1 (–2) cells thick; sporangia in sori, with unicellular paraphyses, both projecting above the cortex
1. Lateral branches not attenuate, solid, with a small-celled cortex and medulla of four large cells in sectional view; sporangia transformed from cortical cells, scattered or grouped, without paraphyses
State Herbarium of South Australia