Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Ectocarpales
Thallus of elachistoid tufts of uniseriate filaments, epiphytic, with clumped filaments below bearing elongate plurilocular organs in a basal zone, with longer, erect assimilatory filaments and hairs from lower filaments; some assimilatory filaments bearing short, senate, plurilocular organs.
Reproduction: Reproduction by basal plurilocular gametangia (?) either basal or senate on assimilatory filaments, and basal, unilocular sporangia.
Life history direct in European species (Pedersen 1981b).
Type species: G. pectinatum (Skottsberg) Kuckuck & Skottsberg in Skottsberg 1921: 9, fig. 3. The type description was clearly based on this species rather than G. ramosum.
Taxonomic notes: Gononema includes some four species, the type and G. ramosum from Antarctic waters, and two species from cold temperate North Atlantic waters (Pederson 1981 b). Most are epiphytes, often on larger brown algae. G. ramosum occurs in the cryptostomata of Adenocystis utricularis, and specimens agreeing well with Skottsberg's descriptions occur on this host on south-eastern Tasmanian coasts.
Gononema in habit is comparable to Elachista, with tufts bearing plurilocular sporangia in the basal zone, and smaller such sporangia on other filaments. All filaments are uniaxial, and phaeophycean hairs arise from lower parts of the tufts. Gononema is currently placed in the Ectocarpaceae, and appears to differ from Streblonema in forming more distinct elachistoid tufts with the sporangia forming a zone in the basal part of the tuft. However some Streblonema species are quite similar to Gononema and further studies of their relationships are clearly needed.
PEDERSEN, P.M. (1981b). The life histories in culture of the brown algae Gononema alariae sp. nov. and G, aecidioides comb. nov. from Greenland. Nord. J. Bot. 1, 263–270.
SKOTTSBERG, C. (1921). Botanische Ergebnisse der Schwedischen Expedition nach Patagonien und dem Feuerlande, 1907–1909. VIII. Marine Algae. I. Phaeophyceae. K. Svenska Vetenskapsakad. Handl. 61(11), 1–56.
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
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State Herbarium of South Australia