|
|
|
|
|
|||||||||||
|
Electronic Flora of South Australia Genus Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Rhodymeniales – Family Rhodymeniaceae
Thallus erect, with sparsely branched, more or less terete, solid, branches bearing hollow, inflated, ovoid to pyriform, usually simple, vesicular laterals, radially or distichously arranged; holdfast discoid or stoloniferous. Structure multiaxial, the solid branches with a small-celled cortex grading to a medulla of compact larger cells. Vesicles not or only slightly mucilaginous, with a cortex 2–3 (–6) cells thick, outer layer of small cells continuous or forming rosettes, grading to a medulla 2–3 cells thick, inner cells larger, with or without rosettes of smaller cells developed inwardly between the larger cells; secretory cells single or in groups, borne on the larger medullary cells.
Reproduction: Gametangial thalli dioecious. Carpogonial branches 4-celled, borne on inner cortical (supporting) cells together with a 2-celled auxiliary cell branch; carposporophyte erect, with a basal fusion cell producing lobes with all cells forming carposporangia. Basal nutritive tissue present, erect filaments slender and tending to disintegrate. Cystocarps protruding both inwards and outwards, smooth, ostiolate with a thick pericarp. Spermatangia in scattered sori, cut off from elongate initials on cortical cells of the vesicles.
Tetrasporangia scattered or in shallow nemathecia on the vesicles, transformed from intercalary cortical cells but with slight and unclear pit-connections to outer cortical cells, cruciately or decussately divided.
Life history triphasic with isomorphic gametophytes and tetrasporophytes.
Type species: B. uvaria Kylin (see Silva 1980a, p. 124). [= B. botryoides (Wulfen) J. Feldmann].
Taxonomic notes: Botryocladia was first established as a subgenus of Chrysymenia by J. Agardh (1851, p. 214) and elevated to a genus by Kylin (1931, p. 17).
A distinctive genus of some 30 species, mainly in tropical to warm temperate waters. Brodie & Guiry (1988a) have given a thorough account of B. ardreana from Portugal.
References:
AGARDH, J.G. (1851). Species Genera et Ordines Algarum. Vol. 2, Part 1, I-XII, 1–336 + index. (Gleerup: Lund.)
BRODIE, J. & GUIRY, M.D. (1988a). Life history and reproduction of Botryocladia ardreana sp. nov. (Rhodyméniales, Rhodophyta) from Portugal. Phycologia 27, 109–130.
KYLIN, H. (1931). Die Florideenordnung Rhodyméniales. Lunds Univ. Årsskr. N.F. Avd. 2, 27 (11), 1–48, Plates 1–20.
SILVA, P.C. (1980a). Remarks on algal nomenclature VI. Taxon 29, 121–145.
The Marine Benthic Flora of Southern Australia Part IIIB complete list of references.
Publication:
Womersley, H.B.S. (28 June, 1996)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIIB. Gracilarialse, Rhodymeniales, Corallinales and Bonnemaisoniales
Reproduced with permission from The Marine Benthic Flora of Southern Australia Part IIIB 1996, by H.B.S. Womersley. Australian Biological Resources Study, Canberra. Copyright Commonwealth of Australia.
|
Email Contact: State Herbarium of South Australia |
|
