Electronic Flora of South Australia Genus Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Gigartinales – Family Halymeniaceae
Thallus with a thick, hard, basal stalk (developing annular growth rings) and lower branches, much branched above with ultimate filiform branchlets forming one to several broad laminae composed largely of a meshwork of branchlets; holdfast massive, divided. An encrusting sponge often grows within the meshwork or over most of the thallus. Structure multiaxial, with a pseudoparenchymatous cortex of ovoid cells and a medulla of more or less parallel filaments, with occasional refractive ganglionic cells. Secondary cortical development prominent on the lower stalk and branches, and filling the interstices between the older filiform branchlets.
Reproduction: Reproduction confined to the special, small, furcate leaflets free from sponge cover, arising on upper parts as extensions of the filiform branchlets.
Sexual thalli monoecious. Carpogonial branch ampullae with a few secondary (and tertiary) filaments and a 2-celled carpogonial branch. Auxiliary cell ampullae with 6–10 secondary and tertiary filaments, slightly converging above. Carposporophytes lying largely within the medulla, with a small basal fusion cell and a distinct involucre derived largely from the ampullary filaments which have elongate cells; ostiole absent.
Tetrasporangia scattered, cut off from inner cortical cells, cruciately divided.
Life history triphasic with isomorphic gametophytes and tetrasporophytes.
Type species: C. natalense Gray 1872: 140.
Taxonomic notes: Five species of Codiophyllum from Western Australia have been described, but these have been reduced to one (C. flabelliforme) by Scott, Wetherbee & Kraft (1984, p. 291). With removal of C. decipiens to the genus Carpopeltis as C. spongeaplexus, this leaves only two species in Codiophyllum, the type from South Africa and C. flabelliforme.
GRAY, I.E. (1872). On Codiophyllum, a new genus of unicellular green algae from Port Natal. Ann. Mag. Nat. Hist. Ser. 4, 10, 139–141, Plate 9.
SCOTT, F.J., WETHERBEE, R. & KRAFT, G.T. (1984). The morphology and development of some prominently stalked southern Australian Halymeniaceae (Cryptonemiales, Rhodophyta). B. The sponge-associated genera Thamnoclonium Kützing and Codiophyllum Gray. J. Phycol. 20, 286–295.
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