Seaweeds of the South African South Coast

 

 

 

 

 

 

 

 

 

 

 

---

 

Order Gelidiales

Family Gelidiaceae

Gelidium micropterum Kutzing 1868: 21, pl.59, figs c-g

Plants brownish-red, rather soft and fleshy, seldom more than 5 cm tall and often shorter; terete stoloniferous basal system bearing flattened erect axes up to 1.2 mm wide and about 150 µm thick, without midrib; Axes two (-three) times pinnately branched, ultimate and penultimate branchlets short, arising at short intervals. Small cortical cells grading into larger medullary cells, rhizines restricted to central medulla. Reproductive structure in ultimate or penultimate branchlets that tend to be roundish or ellipsoidal in outline; bisporangia in sori, transversely divided, about 40 µm long and 30 µm wide.

Collections ecology and regional distribution

Found in the lower eulittoral, rock pools and shallow sublittoral, often on shells of limpets or barnacles. Large plants are uncommon. A prostrate form of this species is common in the “gardens” of the limpet Scutellastra cochlear. Recorded from Buffel River on the northern west coast to central Kwazulu-Natal (3-51) (Tronchin, 2003).

World distribution: Probably restricted to South Africa: Stegenga et al. (1997) question the West African and Namibian records.

Type locality: “Cape of Good Hope” (Silva et al. 1996).

Note: We follow Stegenga et al. (1997) in including the morphological form found in the “gardens” of the limpet Scutellastra cochlear (formerly Patella cochlear). These plants are small, mostly prostrate, with compressed, sometimes “pinnately-lobed prostrate axes and short single or branched erect axes up to ca. 1 cm high”. As in “normal” G. micropterum, sporangial plants bear bisporangia.

 

G. micropterum, lower eulittoral zone, Saldanha Bay.

G. micropterum, detail of frond shape and branching

G. micropterum, thallus apex. Reproduced from Stegenga et al. (1997).

 

References Gelidium micropterum

Kutzing, F.T. 1868. Tabulae phycologicae, 18. Nordhausen, 25 pp., 100pl.

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.

Tronchin, E.M. 2003. The systematics, biology and distribution of the Gelidiaceae (Rhodophyta) of South Africa and related taxa. Ph D thesis, Department of Botany, University of Cape Town, 214 + xv 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.