Electronic Flora of South Australia Genus Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Gigartinales – Family Halymeniaceae
Thallus cartilaginous, complanately and alternately branched, branches compressed to flat, with one to several axes from a discoid holdfast, usually developing a midrib on lower axes. Structure multiaxial, with rounded apices and broad axils, developing a broad cortex with small surface cells, larger and rounded inner cells, forming a pseudoparenchymatous inner cortex without stellate cells, and a narrow medulla (one quarter to one eighth of branch thickness) of densely entwined filaments, without refractive ganglionic cells.
Reproduction: Sexual thalli monoecious, with sexual organs clustered in groups or son near ends of branches. Carpogonial branch ampullae in inner cortex, relatively simple with 1–6 elongate secondary filaments, converging above. Auxiliary cell ampullae larger, with numerous simple or once branched secondary filaments of ovoid to elongate cells. Carposporophyte arising from the auxiliary cell, with a slight to moderate involucre of ampullary filaments and a small ostiole. Spermatangia forming a surface layer in a subterminal sores on branches of the female plant.
Tetrasporangia in slightly raised nemathecia near branch ends, together with numerous multicellular paraphyses, cruciately divided.
Life history triphasic with isomorphic gametophytes and tetrasporophytes.
Type species: C. phyllophora (Hooker & Harvey) Schmitz 1895: 168.
Taxonomic notes: A genus with three species in southern Australia and 8 others from warmer waters of the Indian and Pacific Oceans; the non-Australian species, especially those from Japan and the eastern Pacific, need detailed comparison with the type species.
C. phyllophora is common along southern Australia, especially in the east, C. spongeaplexus is largely western in distribution, while C. elata and C. decipiens occur on the west coast, with C. elata (but not C. decipiens) just extending to southern Australia. C. spongeaplexus is a new name for Codiophyllum decipiens (J. Agardh) Schmitz, which is transferred to Carpopeltis.
Carpopeltis appears to be a monoecious genus with subterminal sori of sex organs, cystocarps and tetrasporangial nemathecia. The southern Australian species are also characterised by a pseudoparenchymatous cortex and narrow medulla.
SCHMITZ, F. (1895). Marine Florideen von Deutsch-Ostafrica. Bot. Jb. 21, 137–177.
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.
KEY TO SPECIES OF CARPOPELTIS
1. Thallus branches covered with a tightly adherent layer of sponge,
1. Thallus free of sponge throughout
2. Thallus branches
2. Thallus branches
State Herbarium of South Australia