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Electronic Flora of South Australia Genus Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Gigartinales – Family Phyllophoraceae
Thallus firm and cartilaginous, with simple to little branched erect ligulate fronds arising from slender, terete, branched, stolons. Structure multiaxial, with a medulla of large, ovoid, thick-walled cells and a cortex of small cells.
Reproduction: Sexual plants dioecious. Carpogonial branches arising in inner cortex, 4-celled, supporting cell acting as auxiliary cell, with the gonimoblast filaments penetrating the medulla with large widely-spaced cells with radiating processes producing short rows of 2–4 carposporangia; cystocarps protruding on both sides of frond, non ostiolate. Spermatangia cut off from outer cortical cells in superficial sori.
Tetrasporophytes with bands of tetrasporangia on both surfaces of young fronds, in catenate rows, cruciately divided.
Life history triphasic with isomorphic sexual and tetrasporophyte generations.
Type (and only) species: S. nicaeensis (Lamouroux ex Duby)Guiry & Hollenberg 1975: 153.
Taxonomic notes: Schottera was segregated from other genera of the Phyllophoraceae on the basis of the distinctive reproductive structures - the carposporophytes with large, thick-walled cells around which the slender filaments and short chains of carposporangia develop, and the bands of catenate rows of tetrasporangia. The carposporophyte structure, on the basis of figs 3 and 4 in Lewis & Kraft (1979), appears little different from that in Australian specimens of Ahnfeltiopsis fastigiatus and A. humilis, where large cells throughout the carposporophyte give rise to rows or clusters of carposporangia on radiating gonimoblast processes; Schotter's illustrations (e.g. 1968, fig. 50) appear rather diagrammatic. However, Schottera has isomorphic gametophytes and tetrasporophytes whereas in Ahnfeltiopsis they are heteromorphic.
References:
GUIRY, M.D. & HOLLENBERG, G.J. (1975). Schottera gen. nov. and Schottera nicaeensis (Lamour. ex Duby) comb. nov. (= Petroglossum nicaeense (Lamour. ex Duby)Schotter) in the British Isles. Br. phycol. J. 10, 149–164.
LEWIS, J.A. & KRAFT, G.T. (1979). Occurrence of a European red alga (Schottera nicaeensis) in southern Australian waters. J. Phycol. 15, 226–230.
The Marine Benthic Flora of Southern Australia Part IIIA complete list of references.
Publication:
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.
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