Seaweeds of the South African South Coast

 

 

 

 

 

 

 

 

 

 

 

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Order Ulvales

Family Ulvaceae

Ulva fasciata Delile 1813: 297 [pl. 58: fig. 5, 1826]

Plants grass green, up to 15(-30) cm tall, rather tough, divided into strap-like blades; blades often undulated and contorted with ruffled edges, 1-3 cm wide, gradually narrowing towards apices. Cells in surface view rounded rectangular to polygonal, unordered., 10-20 µm in diameter in mid-thallus. Lamina distromatic, ca 150 µm thick in mid thallus. Cells in cross section markedly higher than broad (25-35 µm high, 12-18 µm broad in mid-thallus near margins, up to 50 µm high in central mid-thallus and basal region ). Chloroplast parietal, pyrenoids 1-2 (14) per cell. Rhizoidal cells darker and larger than normal vegetative cells.

Collections, ecology and regional distribution

Recorded from False Bay to northern Kwazulu-Natal (17-58). Found in the eulittoral zone, usually in rock pools.

World distribution: widespread in tropical and temperate regions (Guiry & Guiry 2012)

Type locality: Alexandria, Egypt (Silva et al., 1996).

Note: although U. fasciata is reported to be a synonym of U. lactuca Linnaeus (O’Kelly et al., 2010) SA material of the former is genetically different to U. lactuca (L. Kandjengo, pers, comm..) and so we retain the name U. fasciata for our material.

 

Ulva fasciata showing typical blade shape

Ulva fasciata single blade

Ulva fasciata surface view of cells

Ulva fasciata, XS of blade showing cell shape

Ulva fasciata, longitudinal section through base of blade showing central rhizoidal cells

Ulva fasciata: 1, Habit. 2, Surface view of upper thallus. 3, Cross section of upper thallus. 4, Longitudinal section of thallus base. Drawings from Stegenga et al. 1997.

 

References Ulva fasciata:

Delile, A.R. (1813). Description de l'Égypte our recueile et des observations et des recherches qui ont été faites en Égypte pendant l'expédition de l'armée française, publié par les orderes de Sa Majesté l'Empereur Napoléon le Grand.Histoire naturelle. Tom. Second. Histoire naturelle. Vol. 2 (fasc. 2 'troisème livraison') pp. 145-320 [Flore d'Égypte, explication des plances], pls 1-62 [1826]. Paris: Imprimerie Impériale.

Guiry, M.D. & Guiry, G.M. 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched September 2012.

O'Kelly, C.J., Kurihara, A., Shipley, T.C. & Sherwood, A.R. (2010). Molecular assessment of Ulva spp. (Ulvophyceae, Chlorophyta) in the Hawaiian Islands. Journal of Phycology 46(4): 728-735.

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 18 April 2024.