Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Dictyotales – Family Dictyotaceae – Tribe Dictyoteae
Thallus sparingly dichotomously or somewhat laterally and largely complanately branched, 5–50 cm long with branches mostly 1–5 cm broad, axils rounded, basally attached by a rhizoidal holdfast. Growth by a single, transversely lenticular apical cell in a broad apex, segmenting to form monostromatic medullary and cortical layers, with duplication of the medullary or cortical layers in older (especially marginal) parts near the thallus base. Surface of thallus (except for young, actively growing parts or occasionally near the base) moderately to densely covered with short [to 3 (–6) mm long] terete to compressed ramelli.
Reproduction: Tetrasporangia scattered on the thallus surface or occasionally on the compressed ramelli. Sexual thalli rarer, dioecious, with scattered sori of oogonia or antheridia (surrounded by sterile paraphyses) on the thallus surface or occasionally on compressed ramelli.
Life history diplohaplontic and isomorphic.
Lectotype species: G. kunthii (C. Agardh) J. Agardh.
Taxonomic notes: A genus of three species (Papenfuss 1977, p.274), distinguished by the extensive covering of small, terete to ligulate ramelli over the mature thallus.
AGARDH, J.G. (1882). Till algernes systematik. Acta Univ. lund. 17, 1–136, Plates 1–3.
PAPENFUSS, G.F. (1977). Review of the genera of Dictyotales (Phaeophycophyta). Bull. Jap. Soc. Phycol. 25, Suppl. Mem. Iss. Yamada, 271–287.
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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