Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Chordariales – Family Chordariaceae
Thallus simple or with few, usually long, branches or occasionally proliferous, cylindrical, usually 10–50 cm high and 3–10 mm in diameter, often becoming hollow, tomentose with a dense covering of indeterminate cortical filaments. Medulla multiaxial, dense, of parallel filaments near the apices but soon becoming separated by abundant development of hyphae. Subcortex well developed from the outer medullary filaments, of branched, non-pigmented cells. Cortex arising from outer subcortical cells, consisting of unbranched assimilatory filaments, either determinate and without a basal meristem or longer and indeterminate, with a basal meristem. Phaeophycean hairs absent.
Reproduction: Reproduction of sporophyte by ovoid unilocular sporangia, producing meiospores which give rise to microscopic, filamentous, heterothallic gametophytes with plurilocular gametangia producing isogametes (in M. chilensis - Peters & Müller 1986a); plurilocular sporangia may occur on upper cells of cortical filaments.
Life history (in M. chilensis) diplohaplontic and heteromorphic.
Lectotype species: M. sciurus (Harvey) Kuckuck ex Oltmanns.
Taxonomic notes: Myriogloea is credited with some 5 or 6 species (Levring 1939). Nelson & Adams (1983) have reduced the two New Zealand species to one and consider that the Australian M. sciurus does not occur in that country.
The genus is distinguished by absence of phaeophycean hairs, presence of both determinate and indeterminate cortical filaments, and from Papenfussiella (which has the above characters) by a mature medulla of irregularly arranged filaments, largely of hyphae with separated medullary filaments.
LEVRING, T. (1939). Über die Phaeophyceengattungen Myriogloia Kuck. und Haplogloia nov. gen. Bot. Not. 1939, 40–52.
NELSON, W.A. & ADAMS, N.M. (1983). A taxonomic revision of the families Chordariaceae and Chordariopsidaceae (Phaeophyta) in New Zealand. N.Z. J. Bot. 21, 77–92.
OLTMANNS, F. (1922). Morphologie and Biologie der Algen. Vol. 2. (Jena.)
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