Seaweeds of the South African South Coast

 

 

 

 

 

 

 

 

 

 

 

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Order Bonnemaisoniales

Family Bonnemaisoniaceae

Delisea flaccida (Suhr) Papenfuss 1940: 214

Plants bright red, erect, up to 30 (-40) cm tall, with small discoid holdfast; axes compressed, regularly alternately branched, about 3 mm wide and 1 mm thick, with regularly serrated edges. Structure monoaxial, with conspicuous central filament that is visible through the cortex in apical parts of the plant. One lateral arising from each cell of the central filament; laterals alternating and developing in sequence of about four determinate and one indeterminate branch. Cross section of mature parts of thallus showing prominent central cell surrounded by a narrow zone of small cells and a wide pseudoparenchymatous cortex, with cells markedly decreasing in size towards the surface of the thallus.

Plants dioecious. Spermatangia covering most of the surface of foliose branchlets with serrated edges on thallus margins. Cystocarps developing subterminally on indeterminate laterals, sessile, globose, with a terminal ostiole. Tetrasporangia not found.

Collections, ecology and regional distribution

Found from Olifanstbos on the Cape Peninsula (in drift) to the Great Fish River, east of Port Alfred (17-40). Subtidal; commonly found in drift.

World distribution: South African endemic.

Type locality: Algoa Bay (Silva et al. 1996).

 

Delisea flaccida (BOL).

Delisea flaccida (BOL) detail of fronds. Scale marking in cm.

Delisea flaccida 1. Habit. 2-3. Thallus apex. 4. Cross section showing central filament (dotted) and surrounding tissues. Reproduced from Stegenga et al. (1997).

 

References Delisea flaccida

Papenfuss, G. F. 1940. Notes on South African marine algae. Botaniska Notiser I: 200-226.

Silva, P.C., Basson, P.W. & Moe, R.L. 1996. Catalogue of the benthic marine algae of the Indian Ocean. University of California Publications in Botany 79: 1-1259.

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.

 

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.