Electronic Flora of South Australia Species Fact Sheet

Enteromorpha paradoxa (Dillwyn) Kützing 1845: 247; 1856, pl. 35, I.

Phylum Chlorophyta – Order Ulvales – Family Ulvaceae


E. plumosa Kützing 1843: 300, pl. 30.

E. flexuosa sub sp. paradoxa (Dillwyn) Bliding 1963: 79, fig. 42 (Typus II).

Thallus (Fig. 48B) light green, very slender and flaccid, much branched and vaguely spreading, basally attached but often loose-lying in calm situations, 2–20 cm long; younger branches 20–40 µm in diameter, bearing alternately or sometimes oppositely, numerous uniseriate branchlets (Fig. 49C) mostly 0.5–1 mm long and 10–20 (–25) µm in diameter, (4410–40 cells long; older axes (Fig. 49D) 50–200 µm in diameter, central cavity narrow. Cells (Fig. 49C,D) in longitudinal rows and often in transverse rows, but frequently displaced, square to rectangular or polygonal in surface view, 15–40 µm long and 10–25 µm broad (L/B 1–2) in uniseriate branches, 40–50 µm long and 30–40 µm broad in lesser branches, becoming 40–70 µm long and 30–50 µm broad in lower axes; chloroplast parietal, not covering all of the cell wall, with numerous [4–10(44)] small pyrenoids (Fig. 49D).

Reproduction: Reproduction (Bliding 1963, p. 80): generations isomorphic, gametophytes dioecious and anisogamous.

Type from Bangor, Wales.

Selected specimens: Port Lincoln, S. Aust., on tidal flats (Womersley, 23.ii.1959; ADU, A22574). Pelican lagoon, American River inlet, Kangaroo I., S. Aust., low eulittoral (Womersley, 12.i.1950; ADU, A12933). American River inlet, Kangaroo I., S. Aust., 2–3 m deep opposite Muston (Kraft, Johnson & Wickes, 16.iv.1973; ADU, A43736).

Distribution map based
on current data relating to
specimens held in the
State Herbarium of SA

Distribution: Probably cosmopolitan, at least in temperate seas.

In southern Australia, known from Port Lincoln, Outer Harbour and the Coorong, and American River inlet, Kangaroo I., S. Aust., where it is common in Posidonia beds. Probably present in most very sheltered inlets.

Taxonomic notes: E. paradoxa is common in very sheltered habitats and characterised by its very slender, much branched thallus with numerous uniseriate laterals. The cells in lower branches become considerably larger than in other species and usually contain numerous (6–14) small pyrenoids. This corresponds to Bliding's Typus II of subspecies paradoxa.

On southern Australian coasts, this taxon appears to be specifically distinct and it seems preferable to recognise it as a species rather than a subspecies of E. flexuosa as Bliding does.


BLIDING, C. (1963). A critical survey of European taxa in Ulvales. Part I. Capsosiphon, Percursaria, Blidingia, Enteromorpha. Opera Bot. 8(3), 1–160.

KÜTZING, F.T. (1843). Phycologia generalis. (Leipzig.)

KÜTZING, F.T. (1845). Phycologia Germanica. (Köhne: Nordhausen.)

KÜTZING, F.T. (1856). Tabulae Phycologicae. Vol. 6. (Nordhausen.)

The Marine Benthic Flora of Southern Australia Part I complete list of references.

Author: H.B.S. Womersley

Publication: Womersley, H.B.S. (31 May, 1984)
The Marine Benthic Flora of Southern Australia
Part I
©Board of the Botanic Gardens and State Herbarium, Government of South Australia

Illustrations in Womersley Part I, 1984: FIGS 48B, 49C,D.

Figure 48 image

Figure 48   enlarge

Fig. 48. A. Enteromorpha ralfsii (ADU, A52642). B. Enteromorpha paradoxa (ADU, A22574). C. Enteromorpha linza (ADU, A53344). D. Enteromorpha prolifera (ADU, A14129). E. Enteromorpha flexuosa (ADU, A43697).

Figure 49 image

Figure 49   enlarge

Fig. 49. A,B. Enteromorpha ralfsii. A. Part of slender filament (ADU, A52642). B. Part of broader filament (ADU, A53180). C,D. Enteromorpha paradoxa (ADU, A43736). C. Young part of thallus. D. Older part of thallus. E–G. Enteromorpha linza (ADU, A53312). E. Surface view of cells. F. Cross section of young thallus margin. G. Cross section of older thallus margin. H. Enteromorpha prolifera (ADU, A21045). Surface view of cells.

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