Electronic Flora of South Australia Species Fact Sheet
Phylum Chlorophyta – Order Cladophorales – Family Cladophoraceae
Thallus (Figs 66B, 67F) medium to dark green, forming delicate soft tufts of slender short-celled filaments, one to several cm high, attached by rhizoids in the basal region; or forming 1–4 cm long, loose, dark green, entangled, irregular aggregates in protected bays; composed of distinct main axes which mostly bear several strongly developed main laterals (Fig. 67E,F) with which they form pseudodichotomies; the axis and main laterals may be lined with mostly unilateral rows of tapering branchlets (Fig. 67E1), or be bare over long stretches (Fig. 67E2, G,H). Growth almost exclusively intercalary, with branchlets many cells apart on upper filaments (Fig. 67E1,2); some old plants may be densely branched; parent cells usually with a single lateral, occasionally two, in some densely branched plants up to 4 (Fig. 67F) arising at broad angles (45° or more); basal cross walls of laterals steeply inclined to oblique, in older laterals becoming almost horizontal.
Apical cells (Fig. 671) usually tapering to obtuse apices, 20–30 µm in diameter and L/B 1.5–4; ultimate branch cells 22–56 µm in diameter and L/B 1.2–2.5; lower thallus cells 45–70 (–90) µm in diameter, L/B 1–2.5; ratio of basal cell to apical cell diameters 2–4; cell walls 1–3 µm thick above, up to 10 µm thick and lamellate below.
Reproduction: Reproduction (van den Hoek 1982, p. 107) by long moniliform rows of zooidangia.
Type from Cuba (Montagne); in BM (ex K).
Distribution: Widely distributed along tropical to warm temperate Atlantic coasts of America and Africa (van den Hoek 1982, p. 110, map 13)
In southern Australia, known from Falcon Bay, Peel Inlet, W. Aust., thalli 1–4 cm across and forming loose aggregates ("aegagropilas") massed to 10 cm deep in water 1.5 m deep (Gordon, Dec. 1979; UWA 2806; ADU, A51018). Outer Harbour, S. Aust., low eulittoral on piles (Womersley, 15.vi.1955; ADU, A19900).
Taxonomic notes: Cl. montagneana is a slender species, distinguished by the long, unbranched, short-celled filaments, often with scattered spinous branchlets which extend through most of the thallus. Australian material agrees well with that from the Caribbean, but the Peel inlet plants are considerably more robust than the Outer Harbour specimen.
This species shows a superficial resemblance to the erect filaments of Cl. subsimplex, but it lacks this latter species basal tangle of filaments with cells frequently producing a descending rhizoid from their basal poles. Cl. subsimplex is also more robust.
VAN DEN HOEK, C. (1982). A taxonomic revision of the American species of Cladophora (Chlorophyceae) in the North Atlantic Ocean and their geographic distribution. Verh. k. Ned. Akad. Wet. Afd. Natuurkd. Tweede Reeks, Part 78.
The Marine Benthic Flora of Southern Australia Part I complete list of references.
Womersley, H.B.S. (31 May, 1984)
The Marine Benthic Flora of Southern Australia
©Board of the Botanic Gardens and State Herbarium, Government of South Australia
Illustrations in Womersley Part I, 1984: FIGS 66B, 67 E–I.
Figure 66 enlarge
Fig. 66. A. Cladophora hutchinsioides (Holotype). B. Cladophora montagneana (ADU, A51018). C. Cladophora albida (ADU, A52682). D. Cladophora crinalis (ADU, A52690).
Figure 67 enlarge
Fig. 67. A–D. Cladophora hutchinsioides (ADU, A21325). A,B. Upper branch systems. C. Basal cell with attachment rhizoids. D. Upper branches with zooidangia. E–I. Cladophora montagneana (E,F ADU, A51018; G–I, ADU, A19900). El,E2,F. Upper filaments showing branching. G,H. Filaments from upper thallus. I. Apical cells.
State Herbarium of South Australia