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Electronic Flora of South Australia Species Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Gigartinales – Family Gigartinaceae
Selected citations: Fuhrer et al. 1981: pl. 25. Kim 1976: 89.
Synonyms
Gigartina chondroides Hooker & Harvey 1847: 407. J. Agardh 1851: 280. Harvey 1860a: 325; 1863, synop.: xliii. [NON G. chondroides Bory 1828: 154 from Conception, Chile.]
Gigartina flabellata J. Agardh 1851: 265; 1876: 194; 1897: 10. Harvey 1860a: 325; 1863, synop.: xliv. Kützing 1869: 6, pl. 16. [NON G. flabellata Kützing 1849: 751; 1868: 2, pl. 5a, b from South Africa.]
Thallus (Fig. 97D) dark red to brown-red, fading to yellow-brown, 5–15 cm high, erect and more or less rigid, fastigiate with several to many fronds from the holdfast, fronds more or less complanately branched, dichotomous with branching distant below, closer above and flabellate, main branches terete to slightly compressed, linear, 3–5 mm broad, apices rounded, with few to numerous, simple to several times furcate, lateral branchlets 2–3 mm broad, largely distichously arranged, on the upper branches. Holdfast discoid, 3–15 mm across; epilithic. Structure of a compact cortex of anticlinal, subdichotomous filaments, outer cells 1–2 µm in diameter and L/D 1–4, and a medulla of slender anastomosing filaments 3–6 (–10) µm in diameter.
Reproduction: Carpogonial branches 3-celled, arising near the tips of the small lateral branchlets near branch ends, borne on inner cortical (supporting) cells. Cystocarps (Fig. 100C) 400–800 µm across, subterminal with only a short rounded branch end, without involucral ramuli, with moderate enveloping tissue (with some connections to gonimoblast cells but transverse filaments absent or few) surrounding the carposporophyte (Fig. 97E) with its filamentous matrix (only slightly enlarged cells) and clusters of ovoid carposporangia 10–18 µm in diameter, released by cortical disintegration. Spermatangial sori not observed.
Tetrasporangial sori (Fig. 100D) forming annuli 2–3 mm broad, or linear marginal sori 7–10 mm long, around upper, slightly compressed, branchlets. Tetrasporangia (Fig. 97F) developed primarily by transformation of outer medullary cells which also divide laterally, and partly from inner cortical cells, ovoid to elongate-ovoid, 10–20 µm in diameter, cruciately divided.
Mixed-phase plants with cystocarps and tetrasporangia sometimes occur.
Type from Port Phillip Bay, Vic. (Mueller); holotype in Herb. Sonder, MEL, 652113.
Selected specimens: Robe, S. Aust., drift (Womersley, 15.iv.1959; AD, A23002). Cape Lannes, S. Aust., upper sublittoral, wave washed (Womersley, 20.xii.1971; AD, A41189 -"Marine Algae of southern Australia" No. 89; Edyvane, 16.v.1982; AD, A53114 and Womersley, 17.ix.1993; AD, A62993). Blackfellows Caves (S of Carpenter Rocks), S. Aust., 1–2 m deep (Edyvane, 3.ii.1984; AD, A55438). Port Phillip Heads, Vic., drift (Sinkora, Al238, 14.iii.1971; AD, A57308). Bombay Rock, Tamar Est., Tas., upper sublittoral (Womersley, 27.i.1949; AD, A10405). Dover, Tas., drift (Wollaston, 20.viii.1965; AD, A29556). Breaksea I., Port Davey, Tas., low eulittoral (AIMS-NCI, Q66C 5108-S, 15.ii.1991; AD, A61359).
Distribution: Robe, S. Aust., to Port Phillip Heads, Vic., and around Tasmania, just sublittoral on rough-water coasts.
Taxonomic notes: Gigartina muelleriana is a distinctive species with its complanately and subdichotomously branched fronds, terete or only slightly compressed branches, and short lateral (reproductive) branchlets above. Tetrasporangial sori are located between the inner cortex and medulla, with tetrasporangia transformed from outer medullary (and inner cortical) cells and also cut off laterally. This taxon was re-named by Setchell & Gardner (1933, p. 294) since G. flabellata J. Agardh (1851, p. 265) was pre-dated by G. flabellata Kützing (1849, p. 751) from South Africa. Setchell & Gardner based the name on the illustration of Kützing (1869, pl. 16), which was based (as a part mirror image) on Sonder's specimen now in MEL. G. chondroides Hooker & Harvey (1847, p. 407) was based on a single specimen from Sandy Bay, Tas. (Lyall) in Herb. Hooker, which was not located in 1952, but the name is pre-dated by G. chondroides Bory (1828, p. 154) from Conception, Chile.
The New Zealand G. clavifera J. Agardh (1876, p. 194) is superficially similar to G. muelleriana but has slenderer, compressed branches and cystocarps in small laterals with several involucral pinnules.
References:
AGARDH, J.G. (1851). Species Genera et Ordines Algarum. Vol. 2, Part 1, 1–336 + index. (Gleerup: Lund.)
AGARDH, J.G. (1876). Species Genera et Ordines Algarum. Vol. 3, Part 1 - Epicrisis systematis Floridearum, pp. i-vii, 1–724. (Weigel: Leipzig.)
AGARDH, J.G. (1897). Analecta Algologica. Cont. IV. Acta Univ. lund. 33, 1–106, Plates 1, 2.
BORY DE ST-VINCENT, J.B. (1828). In Duperrey, L.I., Voyage autour du monde, exécuté par ordre du Roi, sur la corvette de Sa Majesté, la Coquille, pendant les années 1822, 1823, 1824 et 1825. Botanique, Cryptogamie, pp. 1–300, Plates 1–39. (Bertrand: Paris.)
FUHRER, B., CHRISTIANSON, I.G., CLAYTON, M.N. & ALLENDER, B.M. (1981). Seaweeds of Australia. (Reed: Sydney.)
HARVEY, W.H. (1860a). Algae. In Hooker, J.D., The Botany of the Antarctic Voyage. 111. Flora Tasmaniae. Vol. II, pp. 321–343, Plates 185–196.
HARVEY, W.H. (1863). Phycologia Australica. Vol. 5, Plates 241–300, synop., pp. i-lxxiii. (Reeve: London.)
HOOKER, J.D. & HARVEY, W.H. (1847). Algae Tasmanicae. Lond. J. Bot. 6, 397–417.
KÜTZING, F.T. (1849). Species Algarum. (Leipzig.)
KÜTZING, F.T. (1868). Tabulae Phycologicae. Vol. 18. (Nordhausen.)
KÜTZING, F.T. (1869). Tabulae Phycologicae. Vol. 19. (Nordhausen.)
KIM, D.H. (1976). A study of the development of cystocarps and tetrasporangial sori in Gigartinaceae (Rhodophyta, Gigartinales). Nova Hedwigia 27, 1–146.
SETCHELL, W.A. & GARDNER, N.L. (1933). A preliminary survey of Gigartina, with special reference to its Pacific North American species. Univ. Calif Pubis Bot. 17, 255–340.
SETCHELL, W.A. & GARDNER, N.L. (1934). De Gigartinis. Rev. Algol. 7, 131–138.
The Marine Benthic Flora of Southern Australia Part IIIA complete list of references.
Publication:
Womersley, H.B.S. (14 January, 1994)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIIA, Bangiophyceae and Florideophyceae (to Gigartinales)
Reproduced with permission from The Marine Benthic Flora of Southern Australia Part IIIA 1994, by H.B.S. Womersley. Australian Biological Resources Study, Canberra. Copyright Commonwealth of Australia.
Illustrations in Womersley Part IIIA, 1994: PLATE 4 fig. 3; FIGS 97 D–F, 100C, D.
Plate 4 enlarge
PLATE 4 fig. 1. Tsengia comosa (AD, A61774). fig. 2. Sarcothalia radula (AD, A62995). fig. 3. Gigartina muelleriana at Evans Cave, Cape Lannes, S. Aust. (AD, A62993). fig. 4. Plocamium mertensii at Breaksea I., Albany, W. Aust. (in Murdoch). Photo: J.M. Huisman.
Figure 97 enlarge
Fig. 97. A–C. Gigartina sonderi (A, B, AD, A22670, holotype; C, AD, A53676). A. Habit, cystocarpic plant. B. Section of part of cystocarp. C. Transverse section of branch with shallow, outer medullary tetrasporangial sorus. D–F. Gigartina muelleriana (D, F, AD, A41189; E, AD, A61359). D. Habit. E. Section of part of cystocarp. F. Transverse section of medullary tetrasporangial sorus.
Figure 100 enlarge
Fig. 100. A, B. Gigartina sonderi (A, AD, A20107; B, AD, A49707). A. Branches with cystocarps. B. Branches with tetrasporangial sori. C, D. Gigartina muelleriana (C, AD, A41189; D, AD, .55438). C. Upper branchlets with cystocarps. D. Upper branchlets with tetrasporangial sori. E, F. Gigartina disticha (AD, A54351). E. Upper branchlets with cystocarps and tetrasporangial sori (mixed phase plant). F. Upper branchlets with tetrasporangial sori. G. Gigartina wehliae (AD, A36053). Branchlets with cystocarps. H, L Gigartina pinnata (H, AD, A54353; I, AD, A56935). H. Upper branchlet with cystocarps. I. Upper branchlets with tetrasporangial sori.
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