Family: Thalassiosiraceae Lebour
Scientific name: Cyclotella striata (Kützing) Grunow ex Cleve et Grunow
Genus: Genus Cyclotella (Küzing) Brébisson
Cells usually solitary, but sometimes united in short chains. Frustules short, cylindrical,discoid, rectangular in girdle view, the valve appearing to be undulated; valves circular, valve surface undulate, undulation more evident in the middle area. Middle area punctate, marginal area striate. Chromatophores, numerous rounded bodies are scattered throughout the cell and often lying against the valves (Hendey, 1964).
Coscinodiscus striatus Kützing; Cyclotella dallasiana Smith
Hustedt, 1930: p. 344, Fig. 176; Hendey, 1964: p. 74; Simonsen, 1974: p. 13; Ricard, 1987:p. 159, Fig. 108-111.
Cells discoid, somewhat rectangular in girdle view. Valve circular, strongly undulate, valve surface marked by a diametrical fold, very evident in the central area. Valve surface is divided sharply into two areas, the center being somewhat coarsely punctate, puncta irregularly scattered, and the marginal area, from about half of radius, being radially striate, radial striae 8 in
10 µm; diameter of valve 20-60 µm (Hendey, 1964).
Valve diameter 25-30 µm.
Common marine and brackish-water species, often abundant in estuaries.
Sites of occurrence in RSA:
In Winter 2006 Cruise, this species was frequently found mainly in the northwestern part of the inner RSA (refer sites map). Species has been previously reported from the northern part of the inner RSA (Simonsen, 1974) and from Kuwaiti waters (Al-Yamani et al., 2004; AlKandari et al., 2009).