Electronic Flora of South Australia Genus Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Gelidiales – Family Gelidiaceae
Thallus erect, 10–50 cm high, much branched from compressed to flat cartilaginous blades. Main branches irregularly branched from the margins or surface, usually with a prominent midrib and in some species with wings, and in most species with small surface or marginal determinate proliferations below the apical parts. Plants are generally associated with sponges which cover the blades except near actively growing apices; holdfast fibrous, often hapteroid. Structure uniaxial, with an indistict apical cell giving rise to an outer cortex of small cells with many rhodoplasts, a mid cortex of anticlinal filaments of elongate cells separating dense groups of rhizines, and an inner cortex of relatively large, isodiametric, rounded cells; medulla of longitudinal filaments of cells often with a few rhizines; proliferations and young blades with few rhizines.
Reproduction: Cystocarps in marginal or surface proliferations, swollen, with an ostiole on each side and a central placenta, with terminal carposporangia. Spermatangia formed in surface patches on proliferations.
Tetrasporangia in sori on proliferations, lying in the cortex, cruciately divided.
Life history triphasic with isomorphic tetrasporophytes and gametophytes, the latter usually dioecious.
Type species: P. spissa (Suhr) Kützing 1847: 25.
Taxonomic notes: A genus of some 12 species, in which Norris (1987b) includes Beckerella Kylin (1956, p. 139) on the basis that the surface proliferations are at least in part a response to the presence of sponges. Ptilophora normally has the branches associated with sponge and Beckerella does not.
KÜTZING, F.T. (1847). Diagnosen and Bemerkungen zu neuen oder kritischen Algen. Bot. Zeit. 5, 1–5, 22–25, 33–38, 52–55, 164–167, 177–180, 193–198, 219–223.
KYLIN, H. (1956). Die Gattungen der Rhodophyceen. (Gleerups: Lund.)
NORRIS, R.E. (1987b). A re-evaluation of Ptilophora Kützing and Beckerella Kylin (Gélidiales, Rhodophyceae) with a review of South African species. Bot. Mar. 30, 243–258.
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