Electronic Flora of South Australia Species Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Acrochaetiales – Family Acrochaetiaceae
Selected citations: Garbary et al. 1983: 42, fig. 17.
Rhodochorton porphyrae Drew 1928: 188, pl. 46 figs 70–75.
Colaconema porphyrae (Drew) Woelkerling 1971: 50, figs 20, 27B.
Thallus (Fig. 16I) largely endophytic, usually scarcely emergent from the host, developing from septate or occasionally aseptate spores. Prostrate system (Fig. 16I) consisting of irregularly alternately branched discrete filaments when young, becoming an interwoven weft. Cells (Fig. 16J–L) irregularly swollen to cylindrical in shape, (2.5–) 5–12 (–42) µm in diameter and 12–30 (–100) µm long, L/D 1–5, each cell containing a laminate (becoming stellate) rhodoplast (Fig. 16M) and one pyrenoid. Erect filaments (Fig. 16K, L) mostly simple and 2–3 cells long but occasionally up to 100 µm high and simple or with short irregularly arranged laterals. Cells (4–) 6–9 µm in diameter and 8–18 µm long, rhodoplasts laminate, with a central pyrenoid. Terminal and pseudolateral hairs up to 200 µm long occur.
Reproduction: Monosporangia (Fig. 16K, L) ovoid, 6–9 µm in diameter and 8–14 µm long, sessile or stalked, solitary or occasionally in pairs, terminal or lateral on the erect filaments.
Other reproductive structures unknown.
Type from Lands End, San Francisco, California, U.S.A., in Porphyra perforata; holotype in UC, 294552 (Gardner 3276).
Selected specimens: Wanna, S. Aust., in Porphyra sp., mid eulittoral (Womersley, 21.viii.1967; AD, A31808). Troubridge Light, S. Aust., in Halymenia muelleri, 17 in deep (Shepherd, 4.ii.I 969; AD, A32933). Ellen Point, Vivonne Bay, Kangaroo I., S. Aust., in Porphyra columbina, mid eulittoral (Womersley, 24.viii.1963; AD, A27025). Robe, S. Aust., in P. lucasii, mid eulittoral at slipway (Womersley, 24.viii.1960; AD, A24432). Crawfish Rock, Vic., in P. lucasii, just sublittoral (Watson, 15.ix.1968; AD, A32708).
Distribution: Western N. America; New Zealand.
In southern Australia, from Wanna, S. Aust., to Westernport Bay, Vic., on Porphyra sp. and Halymenia muelleri.
Taxonomic notes: As Woelkerling (1971, p. 51) noted, the relationship between Audouinella americana and A. porphyrae requires clarification when additional material becomes available. Greatly swollen cells occur in both taxa and they share a number of other features, but they apparently differ in width of erect filaments and in monosporangium size and shape.
The relationship of A. porphyrae to A. bonnemaisoniae also still requires clarification. Except for apparent differences in monosporangium size and shape and in cell dimensions of the prostrate filaments, the two taxa appear to be very similar.
DREW, K.M. (1928). A revision of the genera Chantransia, Rhodochorton, and Acrochaetium with descriptions of the marine species of Rhodochorton (Naeg.) gen. emend. on the Pacific Coast of North America. Univ. Calif. Pubis Bot. 14, 139–224, Plates 37–48.
GARBARY, D.J. (1979b). Numerical Taxonomy and generic circumscription in the Acrochaetiaceae (Rhodophyta). Bot. Mar. 22, 477–492.
GARBARY, D.J. (1987). The Acrochaetiaceae (Rhodophyta): An annotated bibliography. Bibl. Phycol. 77, 1–267.
GARBARY, D.J., HANSEN, G.I. & SCAGEL, R.F. (1983). The marine algae of British Columbia and northern Washington: Division Rhodophyta (red algae), Class Florideophyceae, Orders Acrochaetiales and Nemaliales. Syesis 15 (suppl.), 1–102.
WOELKERLING, W.J. (1971). Morphology and taxonomy of the Audouinella complex (Rhodophyta) in southern Australia. Aust. J. Bot. Suppl. 1, 1–91.
The Marine Benthic Flora of Southern Australia Part IIIA complete list of references.
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.
Illustration in Womersley Part IIIA, 1994: FIG. 16 I–M.
Figure 16 enlarge
Fig. 16. A–H. Audouinella liagorae (A–C, E–G, AD, A30883; D, AD, A31371; H, AD, A32055). A. Prostrate system with short erect filaments bearing hairs and monosporangia. B. Prostrate system with monosporangia. C. Cells of an erect filament, each with a rhodoplast and pyrenoid. D. Carpogonium with attached spermatia on trichogyne. E. Immature carposporophyte. F. Mature carposporophyte. G. Erect branches with spermatangia. H. Erect branches with tetrasporangia. 1-M. Audouinella porphyrae (I–K, M, AD, A31808; L, AD, A24432). I. Branching pattern of endophytic filaments, arising from a spore, within the thallus of Porphyra. J. Prostrate filaments with hairs (sessile or with a single basal cell). K. Prostrate filament with short erect filaments with monosporangia. L. As for K, with relatively long erect filaments. M. Cells of prostrate and short erect filaments each with a rhodoplast and pyrenoid, and a monosporangium. N, 0. Audouinella bonnemaisoniae (AD, A32120). N. Part of thallus with monosporangia, within the host thallus. 0. Cells each with a rhodoplast and pyrenoid. [A–H, J–L, N after Woelkerling 1971.
State Herbarium of South Australia