Seaweeds of the South African South Coast

 

 

 

 

 

 

 

 

 

 

 

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Order Nemaliales

Family Helminthocladiaceae

Helminthocladia australis Harvey 1863: 39, pl. 272

Plants cylindrical, mucilaginous, flaccid, bright red, up to 50 cm tall, one to several main axes arising from a common holdfast, axes with numerous simple or re-branched laterals. Main axes between 2 and 10 mm in diameter. Structure multiaxial, with core of longitudinal filaments surrounded by radiating, dichotomously branched cortical (assimilatory) filaments. Terminal cells of cortical filaments swollen, obpyriform, 15-20 µm in diameter. Cells with a central stellate chloroplast and a central pyrenoid. Plants dioecious. Spermatangia in globose to irregular, loose clusters, terminal on assimilatory filaments. Carpogonial filament of 3 cells, subterminal on a cortical filament. Carposporophyte globose, immersed in thallus: gonimoblasts with terminal carposporangia: sterile involucre not well developed.

Collections, ecology and regional distribution

Found from the western side of the Cape Peninsula to Cape Morgan (16-43). In large pools and the sublittoral; probably a spring/summer annual (Stegenga et al. 1997).

World distribution: Also recorded from Australia, China, Japan, Taiwan, Korea and India (Guiry & Guiry 2009).

Type locality: Fremantle, Western Australia (Silva et al 1996).

Note: The South African entity was previously known as H. papenfussii Kylin, but was synonymised with H. australis by Womersley (1965). The reproductive morphology of this species (as H. papenfussii) is detailed by Martin (1939).

 

Helminthocladia australis, fresh specimen from a rock pool, Cape Point.

Helminthocladia australis, closer view of fresh specimen from a rock pool, Cape Point (small Ceramium plants epiphytic on surface).

Helminthocladia australis. 1. Habit (apex). 2. Cross section showing cortical filaments and one carpogonial filament. Reproduced from Stegenga et al. (1997).

 

References Helminthocladia australis

Harvey, WH 1863. Phycologia Australica Vol. 5, Pl. 241-300. London, Lovell Reeve.

Guiry, M.D. & Guiry, G.M. 2009. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched April 2009.

Martin, MT 1939. Some South African Rhodophyceae I. Helminthocladia papenfussii Kylin. Journal of Botany 77: 234-244.

Stegenga, H., Bolton, J.J. and R. J. Anderson. 1997. Seaweeds of the South African west coast. Contributions from the Bolus Herbarium 18: 655 pp.

Womersley, HBS 1965. The Helminthocladiaceae (Rhodophyta) of southern Australia. Australian Journal of Botany 13: 451-487, 75 figs, 7 pls.

 

Cite this record as:

Anderson RJ, Stegenga H, Bolton JJ. 2016. Seaweeds of the South African South Coast.
World Wide Web electronic publication, University of Cape Town, http://southafrseaweeds.uct.ac.za; Accessed on 19 December 2024.