Electronic Flora of South Australia Genus Fact Sheet

Genus HARALDIOPHYLLUM Zinova 1981: 12

Phylum Rhodophyta – Family Delesseriaceae

Thallus erect, foliose, laciniate, subdichotomous or lobed, with short stipes; midrib and veins absent; margins entire, dentate, or with spinous processes. Holdfast discoid, from stolons in some species. Structure. Growth marginal and diffuse, without distinct apical cells. Young blades monostromatic, becoming tristromatic in reproductive areas and polystromatic near the base, cells in vertical rows, cortical cells equivalent.

Reproduction: Gametophytes dioecious. Procarps scattered on both sides of blades, with the primary blade cell cutting off a cover cell (group) apically, followed by a fertile supporting cell which bears a 1–2-celled lateral sterile group on one side, a 4-celled carpogonial branch on the other side, and a single-celled basal sterile group. Carposporophyte with a basal fusion cell and radiating gonimoblast filaments over the cystocarp floor, together with erect filaments, bearing terminal carposporangia replaced from cells below; the fusion cell occurs above the layer of primary cells of the blade, the cells of which are connected by broadened and partly fused pit-connections. Cystocarps swollen, ostiolate; pericarp 3–5 cells thick, cells in anticlinal rows, scarcely thickened around ostiole. Spermatangial sari on both sides of blades, with cortical cells dividing anticlinally to groups of initials which cut off elongate spermatangia.

Tetrasporangial sori ovate, with tetrasporangia in 1 or 2 layers cut off from the central (primary) cells and deflected alternately or from the inner cortical cells, covered by an outer layer of cortical cells.

Type species: H. bonnemaisonii (Kylin) Zinova 1981: 13. See Maggs & Hommersand 1993: 242, fig. 76.

Taxonomic notes: A genus of some 6 species, the type from the British Isles (Maggs & Hommersand 1993, p. 242) and N Europe and 3 species from Australia (Millar & Huisman 1996a: 67).

Haraldiophyllum differs from Nitophyllum in procarp structure (Nitophyllum having one group of cover cells, whereas Haraldiophyllum has two groups) and in the carposporophyte where cells of radiating gonimoblast filaments both fuse laterally and also fuse with vegetative cells on the cystocarp floor. However, this latter character is shown to a varying degree by numerous species in other genera and cannot be used as a distinguishing feature. The difference between Nitophyllum and Haraldiophyllum is hence slight and may not be satisfactory.

References:

MAGGS, C.A. & HOMMERSAND, M.H. (1993). Seaweeds of the British Isles. Vol. 1. Rhodophyta. Part 3A, Ceramiales. (HMSO: London.)

MILLAR, A.J.K. & HUISMAN, J.M. (1996a). Haraldiophyllum erosum comb. nov. (Delesseriaceae, Rhodophyta) from southern and Western Australia. Aust. Syst. Bot. 9, 61–69.

ZINOVA, A.D. (1981). De positione systematica Nitophylli (Myriogrammes) yezoensis (Yamada et Tokida) Mikami (Delesseriaceae). Nov. Syst. Pl. non Vase. 18, 10–15.

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

Author: H. B. S. Womersley

Publication: Womersley, H.B.S. (24 February, 2003)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIID. Ceramiales – Delesseriaceae, Sarcomeniaceae, Rhodomelaceae
Reproduced with permission from The Marine Benthic Flora of Southern Australia Part IIID 2003, by H.B.S. Womersley. Australian Biological Resources Study, Canberra. Copyright Commonwealth of Australia.

KEY TO SPECIES OF HARALDIOPHYLLUM

Email Contact: State Herbarium of South Australia