Family: Chaetocerotaceae Ralfs in Pritchard
Genus: Bacteriastrum Shadbolt
Scientific name: Bacteriastrum furcatum Shadbolt
Bacteriastrum varians Lauder
Allen and Cupp, 1935: p. 132, Fig. 48 (as Bacteriastrum varians); Crosby and Wood, 1958: p. 519, Pl. 38: 60 (as Bacteriastrum varians); Hendey, 1970: p. 121 (as Bacteriastrum varians); Ricard, 1987: p. 217, Figs. 538, 539 (as Bacteriastrum varians); Hasle and Syvertsen, 1997: p.186, Pl. 37.
Cells of nearly equal width and length. Setae 10 to 25, at right angles to chain axis; basal part usually shorter than in B. delicatulum. Apertures small; terminal setae with fine spines arranged in spiral rows. Diameter 30-36 µm (Allen and Cupp, 1935). Terminal setae first transverse to chain axis, then abruptly obliquely curved toward the chain in their outer part (Hasle and Syvertsen, 1997).
Cells diameter 12-14 µm.
Sites of occurrence in RSA:
In Winter 2006 Cruise, this species occurred at various sites (refer sites map), it was quite abundant at some localities; maximum abundance (7.8*10^5 cells/l) was associated with the Strait of Hormuz (St. 14a). It has been previously reported from Kuwaiti shore (Hendey, 1970).