Electronic Flora of South Australia Species Fact Sheet
Phylum Phaeophyta – Order Dictyotales – Family Dictyotaceae – Tribe Zonarieae
Selected citations: Womersley 1967: 223.
Thallus (Fig. 82A) medium to dark brown, 8–16 cm long, complanate, irregularly laterally branched, with a matted rhizoidal holdfast 1–3 mm across and 2–5 mm long; epilithic. Growth by a group of apical cells (Fig. 83E,F) in a rounded to slightly depressed apex. Fronds branched at intervals of usually 1–4 cm, with rounded axils, branches (3–) 5–10 (–12) mm broad and usually broadening above the axils, often with short lateral projections without midrib or veins. Structure (2–) 4 cells (Fig. 83G) and 120–160 µm thick in young parts, 5–6 cells and 240–320 µm thick in older parts, with the cortical cells usually subdivided (Fig. 83H) compared to the larger medullary cells which are somewhat irregularly placed in transverse section; cortical cells 20–40 (–50) µ across in surface view, L/B 0.6–1.5 (–2). Hair tufts (Fig. 83E,H) dense, scattered, persistent, their bases sunk within the thallus, hairs 12–18 µ in diameter.
Type from Lefevre Pen., S. Aust. (Mueller); in MEL, 17076; isotype in ADU, A8289.
Distribution: The Gulf region of South Australia.
Taxonomic notes: Spatoglossum australasicum is a little known and apparently rare species, and no known plants are fertile.
KÜTZING, F.T. (1859). Tabulae Phycologicae. Vol. 9. (Nordhausen.)
WOMERSLEY, H.B.S. (1967). A critical survey of the marine algae of southern Australia. II. Phaeophyta. Aust. J. Bot. 15, 189–270.
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
Illustrations in Womersley Part II, 1997: FIGS 82A, 83 E–H.
Figure 82 enlarge
Fig. 82. A. Spatoglossum australasicum (ADU, A34905). B. Taonia austra/asica (ADU, A50866).
Figure 83 enlarge
Fig. 83. A–D. Distromium multifidum (A–C, ADU, A29525, holotype; D, ADU, A23956). A. Branches with sori of sporangia. B. Branch end with marginal apical cells and sporangia. C. Transverse section of thallus with sporangia. D. Longitudinal section of thallus with a sorus of antheridia. E–H. Spatoglossum australasicum (ADU, A34905). E. Branch apex showing small groups of apical cells and scattered phaeophycean hair tufts. F. Meristem at apex of a branch, showing apical cells and segmentation. G. Longitudinal section from apical cell (right) to mature thallus (left) showing segmentation. H. Transverse section of mature thallus with a sunken phaeophycean hair tuft.
State Herbarium of South Australia