Electronic Flora of South Australia Species Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Acrochaetiales – Family Acrochaetiaceae
Selected citations: Garbary 1987: 25.
Acrochaetium barbadense (Vickers) Boergesen 1915: 45. Abbott 1962a: 83, fig. 1. FIG. 15A–G
Thallus (Fig. 15A, B) largely endophytic within the cortex of Liagora, 400–600 µm high, developing from persistent spores 12–16 (–24) µm in diameter. Prostrate system (Fig. 15B) consisting of creeping, simple to sparingly and irregularly branched discrete filaments. Cells irregular to cylindrical in shape, 7–13 µm in diameter and (12–) 20–30 (–36) µm long. Erect filaments (Fig. 15A, B) simple or sparingly and irregularly branched, up to 600 µm long, tapering slightly above. Cells cylindrical, 7–10 (–18) µm in diameter and (12–) 18–35 (–75) µm long, L/D 2–4 (–8), occasionally 5–6 µm wide in laterals; each cell containing a parietal lobate rhodoplast (Fig. 15C) with a single pyrenoid. Hairs unknown.
Reproduction: Monosporangia (Fig. 15D) ovoid, 8–10 µm in diameter and 13–18 µm long, sessile or stalked, single or in pairs, situated on the lowermost cells of the laterals.
Thalli apparently dioecious. Carpogonia (Fig. 15E) sessile or stalked, axillary or scattered on the erect filaments, dividing transversely after fertilization and forming short gonimoblast filaments with terminal carposporangia (Fig. 15F) 8–9 µm in diameter and 12–15 µm long. Spermatangia (Fig. 15G) ovoid, 2–4 µm in diameter and 4–6 µm long, solitary or in groups of 2–3 on 1–2-celled stalks, mostly situated on the lower cells of lateral branches but occasionally scattered or terminal.
Type from Barbados; in PC.
Known specimen: Marino, S. Aust., drift, in Liagora .farinosa (Womersley, 21.v.1953; AD, A30880). [This collection is recorded by Abbott (1962a, p. 94) as Womersley A18634; the latter number is now that of the AD sheet of the host, Liagora.farinosa Lamouroux.]
Distribution: Barbados; Bermuda; Channel I. (California); Guadalupe I. (Mexico); Hawaii. In southern Australia, from Marino, S. Aust.
Taxonomic notes: Woelkerling (1971, p. 27) placed the record of Abbott (1962a, p. 94) of Acrochaetium trichogloeae Boergesen under A. barbadensis.
ABBOTT, I.A. (1962a). Some Liagora - inhabiting species of Acrochaetium. Occ. Pap. Bernice P. Bishop Mus. 23, 77–120.
BOERGESEN, F. (1915). The marine algae of the Danish West Indies. Part 3. Rhodophyceae. Dansk bot. Ark. 3, 1–80.
GARBARY, D.J. (1987). The Acrochaetiaceae (Rhodophyta): An annotated bibliography. Bibl. Phycol. 77, 1–267.
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.
State Herbarium of South Australia