Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Sporochnales
Thallus 6–16 cm long, with one to a few percurrent, terete, axes and irregularly placed terete laterals, all densely tomentose, attached by a rhizoidal holdfast. Growth from an apical meristem surmounted by a tuft of trichothallic assimilatory filaments. Structure haplostichous, pseudoparenchymatous, with a medulla of elongate cells and cortex developing radially by periclinal divisions, and bearing coarse, simple, scattered, adventitious, trichothallic (but becoming determinate) assimilatory filaments 1–2 mm long over the otherwise smooth surface.
Reproduction: Reproduction unknown.
Life history unknown.
Type species: S. tomentosum Womersley.
Taxonomic notes: Sporochnema is undoubtedly a member of the Sporochnales, even though no reproductive plants have been found. The apical development, structure, and trichothallic apical tufts are all typical of the order, but Sporochnema differs from all other genera in possessing a tomentose cover of simple trichothallic filaments scattered densely over the branches, arising adventitiously from the otherwise smooth-surfaced cortex.
The genus is named for the filamentous cover on an otherwise characteristic sporochnalean plant, and the species for its tomentose appearance.
References: The Marine Benthic Flora of Southern Australia Part II
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
State Herbarium of South Australia