Electronic Flora of South Australia Species Fact Sheet
Phylum Phaeophyta – Order Fucales – Family Cystoseiraceae
Blossevillea expansa Areschoug 1854: 337.
Thallus (Fig. 140A) dark brown, 20–60 cm long, densely branched from a coarse primary axis. Holdfast discoid-conical, 1–2 (–3) cm across; epilithic. Primary axes 2–5 (–10) mm broad and 1–2 (–4) mm thick, with narrower edges, relatively straight with alternately distichous laterals from the axis face and prominent, reflexed, branch residues usually 0.5–1 cm apart; secondary axes 2–10 cm long, distichously and closely branched, usually basally denuded with close and prominent branch residues, not or slightly flexuous. Laterals (Fig. 141D) 3–8 cm long, tristichously (occasionally subdistichously) branched from a 3-sided rhachis, bearing slender, alternately distichous ramuli 0.5–2 (–3) cm long and 0.2–0.6 (–1)mm thick. Vesicles usually present, scattered on laterals and replacing one to several of the lower branches of the ramuli, elongate-ellipsoid, 3–5 (–7) mm long and 1–2 mm broad, petiolate, with an apiculate (when young) or rounded apex.
Reproduction: Thalli monoecious. Receptacles (Fig. 141E,F) usually simple, developed from ends of ultimate branches of ramuli, 0.5–1 (–1.5) cm long and 0.5–1 (–1.5) mm in diameter, terete to slightly compressed, becoming closely torulose, apiculate. Conceptacles bisexual, closely adjacent but with relatively few per receptacle, with ostioles more or less in two rows, with simple paraphyses; oogonia sessile, ovoid, 90–150 µm long and 55–80 µm in diameter; antheridia sessile or on branched paraphyses, elongate-ovoid, 20–25 µm long and 8–10 µm in diameter.
Type from Port Philip, Vic.; in S, probable isotype in MEL, 356.
Selected specimens: Yallingup, W. Aust. (Royce 536, 24.v.1950; PERTH). Cowaramup Bay, W. Aust., 2–3 m deep (Engler & Clarke, 1.ix.1979; ADU, A50655). Brown Point, Yorke Pen., S. Aust., upper sublittoral pools (Womersley, 10.iv.1950; ADU, A13111). Marino, S. Aust., drift (Womersley, 21.v.1953; ADU, A18658). Victor Harbor, S. Aust., drift (Womersley, 14.vii.1963; ADU, A26534). Little Rocky Point, Eastern Cove, Kangaroo I., S. Aust., 2–4 m deep ( Womersley, 22.viii.1963; ADU, A26898). Dutton Beach, Portland, Vic., drift (Beauglehole, 29.xi.1959; ADU, A23977). Leading Lights, Tamar Est., Tas., drift (Levring, 21.ii.1948; ADU, A56004). Huskisson, N.S.W., drift ( Womersley, 13.viii.1959; ADU, A23133). Long Bay, N.S.W. (Lucas, May 1899; NSW).
Distribution: From Yallingup, W. Aust. to Long Bay, N.S.W. and the north coast of Tasmania.
Taxonomic notes: C. expansa is characterised by the robust axes, small, ellipsoid vesicles scattered over the laterals, short, torulose receptacles, and tristichous branching of the laterals. It is a common species in shallow water and deeper pools on coasts of moderate wave action.
ARESCHOUG, J.E. (1854). Phyceae novae et minus cognitae in maribus extraeuropaeis collectae. Ada Reg. Soc. Sci. Upsala, Ser. III, 1, 329–372.
WOMERSLEY, H.B.S. (1964). The morphology and taxonomy of Cystophora and related genera (Phaeophyta). Aust. J. Bot. 12, 53–110, Plates 1–16.
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 140A, 141 D–F.
Figure 140 enlarge
Fig. 140. A. Cystophora expansa (ADU, AI3111). B. Cystophora torulosa (ADU, A9317).
Figure 141 enlarge
Fig. 141. Receptacles of species of Cystophora. A–C. Cystophora monilifera (ADU, A26869). A. A secondary axis with laterals and vesicles. B. An axis apex with a young, tristichously branched, lateral. C. Receptacles. D–F. Cystophora expansa (D, ADU, A26898; E, ADU, A18658; F, ADU, A23133). D. A secondary axis with laterals. E,F. Laterals with receptacles. G. Cystophora torulosa (ADU, A57472). Receptacles.
State Herbarium of South Australia